So I had a chat with ChatGPT about my turbo....
So I had a chat with ChatGPT about my turbo....
After going to my 5th DGRR and talking to other owners about their EFR setups and the low-mid range power they are making, I started thinking about a different turbo setup. The other day, I had a conversation with ChatGPT, and it went down a rabbit hole. I work in cybersecurity and focus on AI, so I know generative AI is just a probability model. It's not always right, and it's not always wrong. Anyways, I am not a tuner or turbo expert, but I would love insight from the braintrust here on how accurate these answers are because it legit might impact which way I decide to go if I wanna change/modify my turbo setup. This is a bit long, but I am very impressed by the depth of the "answers". Now I just need smarter people to confirm or deny the accuracy:
Me: Is the sxe 8380 a good turbo for a mild street port 13b at 14psi if I wanna only make around 400whp
ChatGPT: The BorgWarner SX-E 8380 is **overkill** for your goals — especially on a **mild street port 13B** at **14 psi** targeting only **~400 whp**. Here's why:
### Why the 8380 may not be ideal:
* **Too big for 14 psi**: The 8380 is a large-frame turbo meant for high-flow, high-boost applications (often 600+ WHP). At just 14 psi, it won’t be operating efficiently, leading to **slow spool** and **laggy throttle response**, especially on a rotary that thrives on fast spool.
* **Rotary exhaust energy mismatch**: Rotaries have high exhaust energy, but a mild street port at modest boost may not provide enough to spool an 83mm turbine quickly, especially in lower RPMs.
* **Turbo efficiency**: The 8380 shines at **25–35+ psi**. You're running at nearly half that.
### Better options for 400 WHP on a 13B:
Here are more suitable turbos for your goals:
* **BorgWarner EFR 7670 or 8374** (Internal gate optional): Much better spool, and still capable of 400–500 WHP.
* **Garrett G30-660**: Excellent spool, highly efficient, perfect match for 400 WHP on pump gas at moderate boost.
* **Precision 5858 or 5862**: Proven performers on street-port rotaries in this power range.
* **EFR 7064** (if you can find one): Underrated gem for response and mid-range punch.
### Summary:
If you already have the 8380, you *can* run it, but expect **delayed spool** and not much low-end/midrange. If you want a more responsive, fun-to-drive setup that hits 400 WHP sooner and with more usable powerband, a **smaller, more responsive turbo** is the better match for your engine and boost target.
Let me know if you want help picking between the alternatives.
Me: I have this turbo with a .91 AR T4 divided with dual external waste gates. What are my options if I wanna keep the external waste gates
ChatGPT: Since you already have the **SX-E 8380 with a 0.91 A/R T4 divided turbine housing** and **dual external wastegates**, you’re working with a setup geared toward higher-flow, higher-boost applications. But if you want to **target 400 whp with better spool**, here are your **best options** if you want to **retain the twin-scroll T4 manifold and dual gates**:
---
### **Option 1: Swap to a smaller T4-divided turbo**
Stick with the T4 divided setup and just replace the turbo with something more appropriate:
#### **1. BorgWarner EFR 8374 T4 Twin-Scroll**
* **Rated**: ~550–650 WHP
* **Spools** much faster than the 8380 due to smaller turbine and lightweight Gamma-Ti wheel.
* **Perfect bridge** between spool and top-end.
* Works well at 14–20 psi on a rotary for \~400–450 WHP.
#### **2. Garrett G30-770 or G30-660 w/ T4 divided housing**
* G30-660 supports \~660 HP, G30-770 supports \~770 HP
* **Smaller turbine** than the 8380 = way faster spool.
* Available with T4 divided housings.
* Very responsive on 13B at 14–18 psi.
#### **3. Precision 5862 Gen 2 or 6062**
* You can get these with **T4 divided housings**.
* Supports 400–550 WHP, faster spool, and works well with external gates.
---
### **Option 2: Keep the 8380 and increase boost**
If you want to **stick with the 8380** and are okay tuning for **more boost**, you could push toward **20–24 psi**, where the 8380 becomes more efficient. On E85 or good pump + meth, that could easily get you **450–500 WHP** on a mild street port. But this means:
* Strong fuel system
* Better cooling
* Beefier engine internals or willingness to rebuild sooner
---
### **Option 3: Retune and tweak for best response**
If you want to **stay at 14 psi**, you can:
* Retune for **aggressive ignition and fuel** in midrange
* Use a **split pulse setup correctly** (true divided manifold with matched pairing)
* Run **anti-lag or staged boost** (e.g., CO2 control on gates)
These will **help throttle response**, but it’ll never be as snappy as a smaller turbo.
---
### Summary:
To keep the **external wastegates and divided T4**, your best options are turbos like:
* **EFR 8374 T4 divided**
* **Garrett G30-770 or G30-660 T4**
* **Precision 5862/6062 T4 divided**
They’ll spool faster than the 8380 and make 400+ WHP without needing 25+ psi.
Would you prefer the **fastest spool** possible or are you okay with a bit of lag if it keeps the top-end strong? I can help narrow it down further.
Me: If I had add more boost will it take longer to make full boost in the same rpm range I have today
ChatGPT: Great question — and the answer is a bit nuanced.
### **No, adding more boost does not mean it takes longer to reach full boost in terms of RPM.**
In fact, **you'll likely reach full boost at around the *same RPM*** — or even **a little earlier** — assuming your turbo is operating in its efficient range and your tuning and wastegate control are solid.
---
### **Why?**
Boost onset (or spool) is mostly determined by:
* **Exhaust energy** (engine RPM + load)
* **Turbo size and inertia**
* **Turbine housing A/R**
* **Backpressure vs boost control**
When you raise your boost target via your **wastegate control (spring or boost control solenoid)**:
* The gate stays **closed longer**, which helps build **exhaust pressure** and **spool the turbo faster**.
* More **exhaust energy** is directed at the turbine for a longer time = **faster or earlier spool**.
---
### **But here's the catch:**
* If you’re running a **huge turbo** (like the SX-E 8380) at **low boost** (14 psi), the turbo might be spooling inefficiently — it’s not fully "on cam" at that pressure.
* Increasing to 18–22 psi might make the turbo operate more **efficiently**, and you’ll often hit that higher boost **at the same RPM** as you hit 14 psi now — or **even sooner** because of improved turbine behavior.
---
### **What could slow it down?**
* If your boost control is bad (e.g., poorly tuned solenoid, slow wastegate response).
* If you increase boost **only at higher RPM** (like in staged boost setups).
* If backpressure or fueling becomes a limiting factor.
---
### **Bottom line:**
**No, raising your boost target doesn’t make it take longer to spool.**
You’ll often hit **higher boost in the same or even lower RPM range**, especially with a big turbo like the SX-E 8380. If you’re at 14 psi now, going to 18–22 psi could wake it up significantly **without hurting spool** — it may **improve** it.
If you'd like, I can help you estimate the RPM where you'd hit full boost based on your current setup, or tune for a sharper response.
Me: My 13B is uses E&J Apex seals and uses a turblown stud kit. Will it be strong enough for more boost?
ChatGPT: Yes — your setup with **E&J apex seals** and a **Turblown stud kit** is a **strong foundation**, and **should handle more boost**, but let’s break it down carefully:
---
### **1. E&J Apex Seals**
* E\&J seals are **very strong**, made for high-boost and high-RPM applications.
* They've been used in **drag**, **street**, and **drift** cars running **20–30+ psi** without failure — assuming good tuning and no detonation.
* They're also **forgiving with detonation** compared to OEM or some other aftermarket options.
**Verdict**: Yes, good for **20–30 psi** depending on your tuning, fuel, and cooling.
---
### **2. Turblown Stud Kit**
* The Turblown stud kit is a **solid upgrade** over stock hardware.
* It **improves clamping force** on the rotor housings and irons, which helps prevent lifting under boost.
* It’s usually paired with builds targeting **\~400–600 WHP** and **25+ psi**, so it’s more than enough for your goals.
**Verdict**: Yes, capable of handling much more than 14 psi safely.
---
### **3. Other Things to Check Before Raising Boost**
Here’s what determines if you can safely raise boost to 18–22+ psi:
#### **Tuning**
* Must be **dialed in** on a dyno with **safe AFRs**, **good ignition timing**, and **zero knock**.
* Rotary engines **don’t forgive detonation**, even with tough apex seals.
#### **Fuel System**
* Need injectors and pump(s) to support the extra airflow.
* For 20+ psi on E85, that’s typically **4x 1680cc+** injectors or staged with **2200s**, and a **good fuel pump (or two)**.
#### **Cooling**
* Rotary engines **get hot fast** under boost.
* Ensure you have:
* Efficient **radiator**
* **Oil cooler**
* **Intercooler** that won’t heat soak (air-to-air or water-to-air)
#### **ECU & Sensors**
* Reliable ECU (like Haltech, ECU Master, AEM, etc.) with:
* Boost control
* IAT correction
* Knock detection (if available)
* Safety cuts (overboost, AFR fail-safe)
---
### **Summary:**
With E&J apex seals and the Turblown stud kit, your 13B is **mechanically ready for more boost** — probably up to **20–25 psi safely** if everything else (tune, fuel, cooling) is in order.
You’re not limited by the motor hardware — your limit is mostly **supporting mods and tuning quality**.
Want to walk through the rest of your fuel and cooling setup to see how far you can safely push it?
Me: I’m running a haltech with Injector dynamics 1050cc primaries and 1700 secondary. My fuel pump is a Walbro 450
ChatGPT: Perfect — you're actually in a pretty solid position to **safely increase boost**, especially on **pump gas** or a **pump + meth** setup. Let’s break it down by component:
---
### **Your Setup Overview**
* **ECU**: Haltech — **excellent**, fully capable of precise boost control, safety limits, and tuning. Big plus.
* **Injectors**:
* **ID1050x** primaries
* **ID1700x** secondaries
→ That's **plenty of injector** for 400–500+ WHP on **gasoline**, and still manageable on **E85** if you're under \~450 WHP.
* **Fuel Pump**: Walbro 450 (F90000274 or similar)
* Supports **\~600–700 WHP on gasoline**
* Supports **\~450–500 WHP on E85** (depending on pressure and voltage)
---
### **How Much Boost Can You Run Safely?**
Assuming you're on **pump gas**, your current setup can likely support **up to 20–22 psi** safely on your **13B + SX-E 8380**, making **450–500 WHP** depending on efficiency.
On **E85**, you’re right at the limit around **450 WHP**, depending on your base fuel pressure and how healthy the pump is. If you're aiming higher, you’d want:
* A second pump (e.g., staged)
* Or a bigger single like a **Hellcat 525** or **brushless setup**
---
### **Safety Limits You Should Enable in the Haltech**
* **Overboost cut** (e.g., cut fuel or spark if boost exceeds 22–23 psi)
* **AFR fail-safe** (e.g., cut if AFR >12.5:1 under boost on pump)
* **IAT timing correction** (pull timing if intake temps get too hot)
* **Coolant and oil temp protection** if sensors are installed
---
### **Boost Recommendation**
To wake up the SX-E 8380 and still stay safe:
* Target **18–20 psi** as your **max boost** for now
* Use **Haltech closed-loop boost control**
* Run **conservative timing**, especially on pump gas
That’ll likely land you in the **420–460 WHP** range, where the turbo is happier, and your motor/fuel system are still operating in a safe envelope.
---
### Want More? Add:
* Second Walbro 450 or switch to a return-style dual setup
* Boost-referenced fuel pressure regulator (if not already running one)
* Flex fuel sensor (if not already) to enable E85 tuning safely
---
If you give me your fuel pressure (base), injector duty cycle, or target fuel type, I can calculate a rough **power ceiling** for your exact setup.
Me: I just wanna run pump 93 gas
ChatGPT: Perfect — running **93 octane pump gas** sets a clear ceiling and helps simplify things. Here's what your current setup can **comfortably and safely support** on pump:
---
### **With 93 Octane Pump Gas: Safe Limits**
#### **Injectors (ID1050 + ID1700)**
* On 93, your total injector capacity can safely support **\~500–525 WHP** at reasonable duty cycles.
#### **Walbro 450 Fuel Pump**
* On 93 gas, it’ll support up to **\~600 WHP** (at base pressure of \~43.5 psi and good voltage).
* You’re well within limits here — no upgrade needed.
---
### **Boost Limit on 93 Octane (Critical Point)**
* **93 pump gas limits boost due to knock** — not hardware.
* On a 13B with good cooling and ignition control, you can usually run:
* **16–18 psi safely**
* Up to **20 psi** with very conservative timing, good IATs, and solid tuning
Beyond that, the risk of **detonation rises fast**, even with strong apex seals.
---
### **Estimated Power Output**
With your **SX-E 8380**, mild street port, and 93 octane:
* At **16–17 psi**: \~400–420 WHP
* At **18–20 psi**: \~430–460 WHP (approaching the turbo’s efficiency zone)
* Beyond that: Not recommended on pump unless you add meth injection or switch to E85
---
### **Recommendations**
* **Target 18 psi**, tune conservatively, and monitor knock/EGTs
* Set boost cut at **\~21 psi**
* Keep **IATs below \~120°F** under full boost
* Use Haltech to pull timing based on IAT and coolant temp
---
### **Optional Safety Upgrades**
* **Meth injection** (aqua-mist or AEM) — lets you run 20–22 psi safely on 93
* **Knock sensor/tuning with audio** — Haltech can do this with proper setup
---
### Final Verdict:
Your **13B with E&J apex seals, Turblown studs, Haltech, ID injectors, and Walbro 450** is absolutely **strong enough to run 18–20 psi** on 93 octane. That should net you a responsive, reliable **400–450 WHP** setup if tuned well — and your SX-E 8380 will finally be in its sweet spot.
Let me know if you want help building a safe timing or boost control strategy in Haltech.
Me: Can my stock transmission handle this much power
ChatGPT: Great question — because **your transmission becomes the next weak link** once you start pushing **400+ WHP** through a rotary.
---
### **Assuming You’re Using a Stock FC or FD Transmission:**
#### **1. FC (Turbo II) 5-Speed Transmission**
* **Rated for**: \~350–400 WHP *with care*
* **Reality**: They can handle **\~400 WHP** if:
* You're not launching hard
* Shifts are clean (no power-shifting or clutch dumps)
* You’re not using super sticky tires or high-grip drag radials
But they're **old**, and worn synchros or input shaft play will show quickly at that power.
#### **2. FD 5-Speed Transmission**
* Stronger than FC, better synchronizers and gear materials.
* Handles **\~450–500 WHP** with careful driving
* **More robust**, but still not a fan of hard launches or clutch dumps
#### **3. FD 6-Speed (from RX-8 or JDM FD Type RZ)**
* Surprisingly not stronger than the FD 5-speed
* Still limited to **\~450 WHP**, similar weak points in gear strength
---
### **Known Weak Points**
* 3rd and 4th gear can shear or chip under high torque loads
* Synchros tend to fail if you shift aggressively at high RPMs
* Input shaft or gear teeth can let go with sticky tires + hard launches
---
### **If You Want Reliability at 400–450 WHP:**
#### **Short-Term — What You Can Do:**
* **Clutch**: Use a soft-engaging but strong clutch (Exedy HD, ACT street/strip) — avoid puck-type or harsh race clutches unless you're racing
* **Avoid clutch dumping** or full-throttle shifts
* Add **transmission fluid cooler or better fluid** (like Redline MT-90 or Motul Gear 300)
* Consider **upgraded shifter bushings** for cleaner engagement
#### **Long-Term — If You Want to Push or Abuse It:**
* **Upgrade options**:
* **Tremec T56 Magnum** (very strong but requires adapter, fab, custom driveshaft)
* **Toyota R154/CD009 swaps** (popular, but complex)
* **PWR or OS Giken sequential** (race-only money)
---
### **Verdict**
Your stock FC or FD transmission **can handle 400–450 WHP** on 93 pump gas **if you drive smart**:
* No hard launches
* No power shifting
* Maintain it and expect wear over time
If you want to drag race, drift, or abuse it — start planning a swap.
Let me know your exact trans (FC, FD, or swapped) and I can give you specifics.
Me: It’s a 5 speed FD with ACT HD-M street sprung clutch
ChatGPT: Perfect — your setup is **right on the edge of reliable power** for a street-driven FD:
---
### **Your Transmission: FD 5-Speed**
* **Stronger** than the FC version, with better internals and improved synchronizers.
* Can reliably handle **\~450 WHP** with **moderate driving** — especially if you’re not clutch-dumping or running drag radials.
* Many people push **500 WHP** with it **successfully**, but that’s usually with **very disciplined shifting** or **road-course-only use**.
---
### **Your Clutch: ACT HD-M Street Sprung**
* That’s the **Heavy Duty pressure plate** with the **Modified full-face organic disc**.
* **Torque capacity**: \~430–450 lb-ft at the crank
* Excellent for **street/track combo** — smooth engagement and less drivetrain shock than puck clutches
* **Sprung hub** reduces shock loading on your trans — exactly what you want
**Verdict**: This is an **ideal clutch** for a \~400–450 WHP street rotary. You don’t need to change it unless you're going over 500 WHP or doing repeated standing launches.
---
### **Overall Verdict:**
Your FD 5-speed + ACT HD-M clutch is a **solid combo for 400–450 WHP**:
* It’ll survive spirited driving, track days, and the occasional aggressive pull
* Just **avoid clutch dumps**, **power shifting**, and **sticky tires on prep** unless you’re ready for the risk
* Consider upgrading to a **driveshaft safety loop** and inspect the trans mount
You're right in the sweet spot — strong enough to enjoy real power without needing to swap gearboxes. Let me know if you want tips for keeping your trans alive at this level (fluid, bushings, etc.).
Me: Is the sxe 8380 a good turbo for a mild street port 13b at 14psi if I wanna only make around 400whp
ChatGPT: The BorgWarner SX-E 8380 is **overkill** for your goals — especially on a **mild street port 13B** at **14 psi** targeting only **~400 whp**. Here's why:
### Why the 8380 may not be ideal:
* **Too big for 14 psi**: The 8380 is a large-frame turbo meant for high-flow, high-boost applications (often 600+ WHP). At just 14 psi, it won’t be operating efficiently, leading to **slow spool** and **laggy throttle response**, especially on a rotary that thrives on fast spool.
* **Rotary exhaust energy mismatch**: Rotaries have high exhaust energy, but a mild street port at modest boost may not provide enough to spool an 83mm turbine quickly, especially in lower RPMs.
* **Turbo efficiency**: The 8380 shines at **25–35+ psi**. You're running at nearly half that.
### Better options for 400 WHP on a 13B:
Here are more suitable turbos for your goals:
* **BorgWarner EFR 7670 or 8374** (Internal gate optional): Much better spool, and still capable of 400–500 WHP.
* **Garrett G30-660**: Excellent spool, highly efficient, perfect match for 400 WHP on pump gas at moderate boost.
* **Precision 5858 or 5862**: Proven performers on street-port rotaries in this power range.
* **EFR 7064** (if you can find one): Underrated gem for response and mid-range punch.
### Summary:
If you already have the 8380, you *can* run it, but expect **delayed spool** and not much low-end/midrange. If you want a more responsive, fun-to-drive setup that hits 400 WHP sooner and with more usable powerband, a **smaller, more responsive turbo** is the better match for your engine and boost target.
Let me know if you want help picking between the alternatives.
Me: I have this turbo with a .91 AR T4 divided with dual external waste gates. What are my options if I wanna keep the external waste gates
ChatGPT: Since you already have the **SX-E 8380 with a 0.91 A/R T4 divided turbine housing** and **dual external wastegates**, you’re working with a setup geared toward higher-flow, higher-boost applications. But if you want to **target 400 whp with better spool**, here are your **best options** if you want to **retain the twin-scroll T4 manifold and dual gates**:
---
### **Option 1: Swap to a smaller T4-divided turbo**
Stick with the T4 divided setup and just replace the turbo with something more appropriate:
#### **1. BorgWarner EFR 8374 T4 Twin-Scroll**
* **Rated**: ~550–650 WHP
* **Spools** much faster than the 8380 due to smaller turbine and lightweight Gamma-Ti wheel.
* **Perfect bridge** between spool and top-end.
* Works well at 14–20 psi on a rotary for \~400–450 WHP.
#### **2. Garrett G30-770 or G30-660 w/ T4 divided housing**
* G30-660 supports \~660 HP, G30-770 supports \~770 HP
* **Smaller turbine** than the 8380 = way faster spool.
* Available with T4 divided housings.
* Very responsive on 13B at 14–18 psi.
#### **3. Precision 5862 Gen 2 or 6062**
* You can get these with **T4 divided housings**.
* Supports 400–550 WHP, faster spool, and works well with external gates.
---
### **Option 2: Keep the 8380 and increase boost**
If you want to **stick with the 8380** and are okay tuning for **more boost**, you could push toward **20–24 psi**, where the 8380 becomes more efficient. On E85 or good pump + meth, that could easily get you **450–500 WHP** on a mild street port. But this means:
* Strong fuel system
* Better cooling
* Beefier engine internals or willingness to rebuild sooner
---
### **Option 3: Retune and tweak for best response**
If you want to **stay at 14 psi**, you can:
* Retune for **aggressive ignition and fuel** in midrange
* Use a **split pulse setup correctly** (true divided manifold with matched pairing)
* Run **anti-lag or staged boost** (e.g., CO2 control on gates)
These will **help throttle response**, but it’ll never be as snappy as a smaller turbo.
---
### Summary:
To keep the **external wastegates and divided T4**, your best options are turbos like:
* **EFR 8374 T4 divided**
* **Garrett G30-770 or G30-660 T4**
* **Precision 5862/6062 T4 divided**
They’ll spool faster than the 8380 and make 400+ WHP without needing 25+ psi.
Would you prefer the **fastest spool** possible or are you okay with a bit of lag if it keeps the top-end strong? I can help narrow it down further.
Me: If I had add more boost will it take longer to make full boost in the same rpm range I have today
ChatGPT: Great question — and the answer is a bit nuanced.
### **No, adding more boost does not mean it takes longer to reach full boost in terms of RPM.**
In fact, **you'll likely reach full boost at around the *same RPM*** — or even **a little earlier** — assuming your turbo is operating in its efficient range and your tuning and wastegate control are solid.
---
### **Why?**
Boost onset (or spool) is mostly determined by:
* **Exhaust energy** (engine RPM + load)
* **Turbo size and inertia**
* **Turbine housing A/R**
* **Backpressure vs boost control**
When you raise your boost target via your **wastegate control (spring or boost control solenoid)**:
* The gate stays **closed longer**, which helps build **exhaust pressure** and **spool the turbo faster**.
* More **exhaust energy** is directed at the turbine for a longer time = **faster or earlier spool**.
---
### **But here's the catch:**
* If you’re running a **huge turbo** (like the SX-E 8380) at **low boost** (14 psi), the turbo might be spooling inefficiently — it’s not fully "on cam" at that pressure.
* Increasing to 18–22 psi might make the turbo operate more **efficiently**, and you’ll often hit that higher boost **at the same RPM** as you hit 14 psi now — or **even sooner** because of improved turbine behavior.
---
### **What could slow it down?**
* If your boost control is bad (e.g., poorly tuned solenoid, slow wastegate response).
* If you increase boost **only at higher RPM** (like in staged boost setups).
* If backpressure or fueling becomes a limiting factor.
---
### **Bottom line:**
**No, raising your boost target doesn’t make it take longer to spool.**
You’ll often hit **higher boost in the same or even lower RPM range**, especially with a big turbo like the SX-E 8380. If you’re at 14 psi now, going to 18–22 psi could wake it up significantly **without hurting spool** — it may **improve** it.
If you'd like, I can help you estimate the RPM where you'd hit full boost based on your current setup, or tune for a sharper response.
Me: My 13B is uses E&J Apex seals and uses a turblown stud kit. Will it be strong enough for more boost?
ChatGPT: Yes — your setup with **E&J apex seals** and a **Turblown stud kit** is a **strong foundation**, and **should handle more boost**, but let’s break it down carefully:
---
### **1. E&J Apex Seals**
* E\&J seals are **very strong**, made for high-boost and high-RPM applications.
* They've been used in **drag**, **street**, and **drift** cars running **20–30+ psi** without failure — assuming good tuning and no detonation.
* They're also **forgiving with detonation** compared to OEM or some other aftermarket options.
**Verdict**: Yes, good for **20–30 psi** depending on your tuning, fuel, and cooling.
---
### **2. Turblown Stud Kit**
* The Turblown stud kit is a **solid upgrade** over stock hardware.
* It **improves clamping force** on the rotor housings and irons, which helps prevent lifting under boost.
* It’s usually paired with builds targeting **\~400–600 WHP** and **25+ psi**, so it’s more than enough for your goals.
**Verdict**: Yes, capable of handling much more than 14 psi safely.
---
### **3. Other Things to Check Before Raising Boost**
Here’s what determines if you can safely raise boost to 18–22+ psi:
#### **Tuning**
* Must be **dialed in** on a dyno with **safe AFRs**, **good ignition timing**, and **zero knock**.
* Rotary engines **don’t forgive detonation**, even with tough apex seals.
#### **Fuel System**
* Need injectors and pump(s) to support the extra airflow.
* For 20+ psi on E85, that’s typically **4x 1680cc+** injectors or staged with **2200s**, and a **good fuel pump (or two)**.
#### **Cooling**
* Rotary engines **get hot fast** under boost.
* Ensure you have:
* Efficient **radiator**
* **Oil cooler**
* **Intercooler** that won’t heat soak (air-to-air or water-to-air)
#### **ECU & Sensors**
* Reliable ECU (like Haltech, ECU Master, AEM, etc.) with:
* Boost control
* IAT correction
* Knock detection (if available)
* Safety cuts (overboost, AFR fail-safe)
---
### **Summary:**
With E&J apex seals and the Turblown stud kit, your 13B is **mechanically ready for more boost** — probably up to **20–25 psi safely** if everything else (tune, fuel, cooling) is in order.
You’re not limited by the motor hardware — your limit is mostly **supporting mods and tuning quality**.
Want to walk through the rest of your fuel and cooling setup to see how far you can safely push it?
Me: I’m running a haltech with Injector dynamics 1050cc primaries and 1700 secondary. My fuel pump is a Walbro 450
ChatGPT: Perfect — you're actually in a pretty solid position to **safely increase boost**, especially on **pump gas** or a **pump + meth** setup. Let’s break it down by component:
---
### **Your Setup Overview**
* **ECU**: Haltech — **excellent**, fully capable of precise boost control, safety limits, and tuning. Big plus.
* **Injectors**:
* **ID1050x** primaries
* **ID1700x** secondaries
→ That's **plenty of injector** for 400–500+ WHP on **gasoline**, and still manageable on **E85** if you're under \~450 WHP.
* **Fuel Pump**: Walbro 450 (F90000274 or similar)
* Supports **\~600–700 WHP on gasoline**
* Supports **\~450–500 WHP on E85** (depending on pressure and voltage)
---
### **How Much Boost Can You Run Safely?**
Assuming you're on **pump gas**, your current setup can likely support **up to 20–22 psi** safely on your **13B + SX-E 8380**, making **450–500 WHP** depending on efficiency.
On **E85**, you’re right at the limit around **450 WHP**, depending on your base fuel pressure and how healthy the pump is. If you're aiming higher, you’d want:
* A second pump (e.g., staged)
* Or a bigger single like a **Hellcat 525** or **brushless setup**
---
### **Safety Limits You Should Enable in the Haltech**
* **Overboost cut** (e.g., cut fuel or spark if boost exceeds 22–23 psi)
* **AFR fail-safe** (e.g., cut if AFR >12.5:1 under boost on pump)
* **IAT timing correction** (pull timing if intake temps get too hot)
* **Coolant and oil temp protection** if sensors are installed
---
### **Boost Recommendation**
To wake up the SX-E 8380 and still stay safe:
* Target **18–20 psi** as your **max boost** for now
* Use **Haltech closed-loop boost control**
* Run **conservative timing**, especially on pump gas
That’ll likely land you in the **420–460 WHP** range, where the turbo is happier, and your motor/fuel system are still operating in a safe envelope.
---
### Want More? Add:
* Second Walbro 450 or switch to a return-style dual setup
* Boost-referenced fuel pressure regulator (if not already running one)
* Flex fuel sensor (if not already) to enable E85 tuning safely
---
If you give me your fuel pressure (base), injector duty cycle, or target fuel type, I can calculate a rough **power ceiling** for your exact setup.
Me: I just wanna run pump 93 gas
ChatGPT: Perfect — running **93 octane pump gas** sets a clear ceiling and helps simplify things. Here's what your current setup can **comfortably and safely support** on pump:
---
### **With 93 Octane Pump Gas: Safe Limits**
#### **Injectors (ID1050 + ID1700)**
* On 93, your total injector capacity can safely support **\~500–525 WHP** at reasonable duty cycles.
#### **Walbro 450 Fuel Pump**
* On 93 gas, it’ll support up to **\~600 WHP** (at base pressure of \~43.5 psi and good voltage).
* You’re well within limits here — no upgrade needed.
---
### **Boost Limit on 93 Octane (Critical Point)**
* **93 pump gas limits boost due to knock** — not hardware.
* On a 13B with good cooling and ignition control, you can usually run:
* **16–18 psi safely**
* Up to **20 psi** with very conservative timing, good IATs, and solid tuning
Beyond that, the risk of **detonation rises fast**, even with strong apex seals.
---
### **Estimated Power Output**
With your **SX-E 8380**, mild street port, and 93 octane:
* At **16–17 psi**: \~400–420 WHP
* At **18–20 psi**: \~430–460 WHP (approaching the turbo’s efficiency zone)
* Beyond that: Not recommended on pump unless you add meth injection or switch to E85
---
### **Recommendations**
* **Target 18 psi**, tune conservatively, and monitor knock/EGTs
* Set boost cut at **\~21 psi**
* Keep **IATs below \~120°F** under full boost
* Use Haltech to pull timing based on IAT and coolant temp
---
### **Optional Safety Upgrades**
* **Meth injection** (aqua-mist or AEM) — lets you run 20–22 psi safely on 93
* **Knock sensor/tuning with audio** — Haltech can do this with proper setup
---
### Final Verdict:
Your **13B with E&J apex seals, Turblown studs, Haltech, ID injectors, and Walbro 450** is absolutely **strong enough to run 18–20 psi** on 93 octane. That should net you a responsive, reliable **400–450 WHP** setup if tuned well — and your SX-E 8380 will finally be in its sweet spot.
Let me know if you want help building a safe timing or boost control strategy in Haltech.
Me: Can my stock transmission handle this much power
ChatGPT: Great question — because **your transmission becomes the next weak link** once you start pushing **400+ WHP** through a rotary.
---
### **Assuming You’re Using a Stock FC or FD Transmission:**
#### **1. FC (Turbo II) 5-Speed Transmission**
* **Rated for**: \~350–400 WHP *with care*
* **Reality**: They can handle **\~400 WHP** if:
* You're not launching hard
* Shifts are clean (no power-shifting or clutch dumps)
* You’re not using super sticky tires or high-grip drag radials
But they're **old**, and worn synchros or input shaft play will show quickly at that power.
#### **2. FD 5-Speed Transmission**
* Stronger than FC, better synchronizers and gear materials.
* Handles **\~450–500 WHP** with careful driving
* **More robust**, but still not a fan of hard launches or clutch dumps
#### **3. FD 6-Speed (from RX-8 or JDM FD Type RZ)**
* Surprisingly not stronger than the FD 5-speed
* Still limited to **\~450 WHP**, similar weak points in gear strength
---
### **Known Weak Points**
* 3rd and 4th gear can shear or chip under high torque loads
* Synchros tend to fail if you shift aggressively at high RPMs
* Input shaft or gear teeth can let go with sticky tires + hard launches
---
### **If You Want Reliability at 400–450 WHP:**
#### **Short-Term — What You Can Do:**
* **Clutch**: Use a soft-engaging but strong clutch (Exedy HD, ACT street/strip) — avoid puck-type or harsh race clutches unless you're racing
* **Avoid clutch dumping** or full-throttle shifts
* Add **transmission fluid cooler or better fluid** (like Redline MT-90 or Motul Gear 300)
* Consider **upgraded shifter bushings** for cleaner engagement
#### **Long-Term — If You Want to Push or Abuse It:**
* **Upgrade options**:
* **Tremec T56 Magnum** (very strong but requires adapter, fab, custom driveshaft)
* **Toyota R154/CD009 swaps** (popular, but complex)
* **PWR or OS Giken sequential** (race-only money)
---
### **Verdict**
Your stock FC or FD transmission **can handle 400–450 WHP** on 93 pump gas **if you drive smart**:
* No hard launches
* No power shifting
* Maintain it and expect wear over time
If you want to drag race, drift, or abuse it — start planning a swap.
Let me know your exact trans (FC, FD, or swapped) and I can give you specifics.
Me: It’s a 5 speed FD with ACT HD-M street sprung clutch
ChatGPT: Perfect — your setup is **right on the edge of reliable power** for a street-driven FD:
---
### **Your Transmission: FD 5-Speed**
* **Stronger** than the FC version, with better internals and improved synchronizers.
* Can reliably handle **\~450 WHP** with **moderate driving** — especially if you’re not clutch-dumping or running drag radials.
* Many people push **500 WHP** with it **successfully**, but that’s usually with **very disciplined shifting** or **road-course-only use**.
---
### **Your Clutch: ACT HD-M Street Sprung**
* That’s the **Heavy Duty pressure plate** with the **Modified full-face organic disc**.
* **Torque capacity**: \~430–450 lb-ft at the crank
* Excellent for **street/track combo** — smooth engagement and less drivetrain shock than puck clutches
* **Sprung hub** reduces shock loading on your trans — exactly what you want
**Verdict**: This is an **ideal clutch** for a \~400–450 WHP street rotary. You don’t need to change it unless you're going over 500 WHP or doing repeated standing launches.
---
### **Overall Verdict:**
Your FD 5-speed + ACT HD-M clutch is a **solid combo for 400–450 WHP**:
* It’ll survive spirited driving, track days, and the occasional aggressive pull
* Just **avoid clutch dumps**, **power shifting**, and **sticky tires on prep** unless you’re ready for the risk
* Consider upgrading to a **driveshaft safety loop** and inspect the trans mount
You're right in the sweet spot — strong enough to enjoy real power without needing to swap gearboxes. Let me know if you want tips for keeping your trans alive at this level (fluid, bushings, etc.).
Based on the capability claims of 400-500whp for and EFR7670, it sounds like ChatGPT is applying the standard piston model of 10hp to lb/min of compressor flow. I believe the commonly accepted ratio for a 13b is 7.5-8hp per lb/min. Multiply the AI numbers by .75 for a more realistic projection.
I did reach out to my tuner and he said to tell GPT that I'm already using Spool Assist and see how the answers change. Now it says:
Nice — using **spool assist (aka anti-lag or staged ignition retard/extra fuel)** on your **BorgWarner SX-E 8380** is a smart move, especially since that turbo is on the **larger** side for a 13B at moderate boost.
Here’s how that plays into your overall setup:
---
### 🔧 **What Spool Assist Does for You**
* **Earlier boost onset**: Keeps exhaust energy high even at low RPMs or part-throttle.
* **Improved driveability**: Helps offset the lag from the large .91 A/R divided housing.
* **Makes big turbo feel smaller**: Great for street and tight track use.
You're essentially making the 8380 behave more like an EFR 8374 or even a 7670 in lower RPMs — **without sacrificing the top-end punch**.
---
### ⚠️ Things to Watch With Spool Assist
1. **EGT (Exhaust Gas Temperature)**
* Spool assist can drive EGTs **very high** during on/off throttle transitions.
* Make sure your **EGT sensors** are in place and healthy.
* If temps are routinely above \~1600–1700°F pre-turbo, consider dialing it back.
2. **Apex Seal Safety**
* You’re running **E\&J seals**, which are very strong — but if anti-lag is too aggressive, you could still risk:
* Chamber pressure spikes
* Rotor housing hot spots
3. **Turbo Life**
* Constant anti-lag can reduce the life of the **thrust bearing**, especially in journal-bearing turbos like the SX-E.
* Consider a turbo timer or cooldown strategy if you’re using it aggressively.
4. **Fuel Consumption + Oil Dilution**
* Rich mixtures during spool assist can lead to oil wash. Monitor oil condition and change it more frequently.
---
### 🧠 Haltech Spool Assist Tuning Tips
* **Use IAT compensation**: Pull back spool assist if intake temps climb (e.g., 120°F+).
* **Retard limit**: Don’t go past **-15° to -20°** ignition timing under spool assist unless you have a specific need — it can spike EGTs quickly.
* **Cut at high TPS or high MAP**: Once you're in boost, disable spool assist to avoid fighting combustion.
---
### Final Verdict:
✅ You're using your turbo **more effectively** with spool assist — which makes a huge difference on a 13B with a large-frame turbo like the SX-E 8380.
💡 Just monitor EGTs, IATs, and fuel condition — and you’ve got a **very dialed-in, responsive, and potent street setup** that will surprise people.
If you want, I can walk you through a sample Haltech spool assist table (ignition + fuel) based on your goals.
Nice — using **spool assist (aka anti-lag or staged ignition retard/extra fuel)** on your **BorgWarner SX-E 8380** is a smart move, especially since that turbo is on the **larger** side for a 13B at moderate boost.
Here’s how that plays into your overall setup:
---
### 🔧 **What Spool Assist Does for You**
* **Earlier boost onset**: Keeps exhaust energy high even at low RPMs or part-throttle.
* **Improved driveability**: Helps offset the lag from the large .91 A/R divided housing.
* **Makes big turbo feel smaller**: Great for street and tight track use.
You're essentially making the 8380 behave more like an EFR 8374 or even a 7670 in lower RPMs — **without sacrificing the top-end punch**.
---
### ⚠️ Things to Watch With Spool Assist
1. **EGT (Exhaust Gas Temperature)**
* Spool assist can drive EGTs **very high** during on/off throttle transitions.
* Make sure your **EGT sensors** are in place and healthy.
* If temps are routinely above \~1600–1700°F pre-turbo, consider dialing it back.
2. **Apex Seal Safety**
* You’re running **E\&J seals**, which are very strong — but if anti-lag is too aggressive, you could still risk:
* Chamber pressure spikes
* Rotor housing hot spots
3. **Turbo Life**
* Constant anti-lag can reduce the life of the **thrust bearing**, especially in journal-bearing turbos like the SX-E.
* Consider a turbo timer or cooldown strategy if you’re using it aggressively.
4. **Fuel Consumption + Oil Dilution**
* Rich mixtures during spool assist can lead to oil wash. Monitor oil condition and change it more frequently.
---
### 🧠 Haltech Spool Assist Tuning Tips
* **Use IAT compensation**: Pull back spool assist if intake temps climb (e.g., 120°F+).
* **Retard limit**: Don’t go past **-15° to -20°** ignition timing under spool assist unless you have a specific need — it can spike EGTs quickly.
* **Cut at high TPS or high MAP**: Once you're in boost, disable spool assist to avoid fighting combustion.
---
### Final Verdict:
✅ You're using your turbo **more effectively** with spool assist — which makes a huge difference on a 13B with a large-frame turbo like the SX-E 8380.
💡 Just monitor EGTs, IATs, and fuel condition — and you’ve got a **very dialed-in, responsive, and potent street setup** that will surprise people.
If you want, I can walk you through a sample Haltech spool assist table (ignition + fuel) based on your goals.
and my tuner just shot down GPT:
Tuner: I think Chat GPT is confusing spool assist (which only clamps down the Wastegate until a few psi away from target boost ) with anti-lag which does other things like retard timing and such , so none of the( things to watch) apply.
Tuner: I think Chat GPT is confusing spool assist (which only clamps down the Wastegate until a few psi away from target boost ) with anti-lag which does other things like retard timing and such , so none of the( things to watch) apply.
Joined: Mar 2001
Posts: 31,837
Likes: 3,234
From: https://www2.mazda.com/en/100th/
i've been running stuff through our work Chat thing. it seems to do pretty well with actual engineering stuff, (we are going to use it to tune my friends ECU) that being said you do need to be really exact.
i've asked it a little bit differently, its like if i have a Mazda 13B at 7000rpm, and 14psi how many lbs per minute is it going to move.
in real life a turbo will do best when its in its peak efficiency area. basically, there are two parts. one is that temps are higher than they would be if the turbo was in the zone. but also it takes more power to drive the compressor, so backpressure will be higher. obviously if the turbo is small, you would expect high backpressure. but too big turning slowly is also bad.
we kind of get pre and post compressor temp and pressures by default.
but i went and measured pre and post turbine pressures on mine, and i was surprised.
i've asked it a little bit differently, its like if i have a Mazda 13B at 7000rpm, and 14psi how many lbs per minute is it going to move.
in real life a turbo will do best when its in its peak efficiency area. basically, there are two parts. one is that temps are higher than they would be if the turbo was in the zone. but also it takes more power to drive the compressor, so backpressure will be higher. obviously if the turbo is small, you would expect high backpressure. but too big turning slowly is also bad.
we kind of get pre and post compressor temp and pressures by default.
but i went and measured pre and post turbine pressures on mine, and i was surprised.
Arrogant Wankeler
Joined: Nov 2006
Posts: 1,008
Likes: 231
From: Hunter Valley NSW Australia
Based on the capability claims of 400-500whp for and EFR7670, it sounds like ChatGPT is applying the standard piston model of 10hp to lb/min of compressor flow. I believe the commonly accepted ratio for a 13b is 7.5-8hp per lb/min. Multiply the AI numbers by .75 for a more realistic projection.
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I have discussed 13b, wankel engines and turboes at length with ChatGPT. It can do basic calculations if asked, but i can get it to agree with anything i tell it.
My goal was to establish a solid argument for the 0.7 piston/wankel turbo size difference. Which is what @fendamonky talks about in his post.
While giving me a lot of text and arguments, to much was just parroting and almost nothing was solid math.
My goal was to establish a solid argument for the 0.7 piston/wankel turbo size difference. Which is what @fendamonky talks about in his post.
While giving me a lot of text and arguments, to much was just parroting and almost nothing was solid math.
I have discussed 13b, wankel engines and turboes at length with ChatGPT. It can do basic calculations if asked, but i can get it to agree with anything i tell it.
My goal was to establish a solid argument for the 0.7 piston/wankel turbo size difference. Which is what @fendamonky talks about in his post.
While giving me a lot of text and arguments, to much was just parroting and almost nothing was solid math.
My goal was to establish a solid argument for the 0.7 piston/wankel turbo size difference. Which is what @fendamonky talks about in his post.
While giving me a lot of text and arguments, to much was just parroting and almost nothing was solid math.
Senior Member
Joined: Jun 2010
Posts: 476
Likes: 240
From: Instagram - Copyninja_FD
I would take whatever AI says about rotary tuning and turbo matching and projected rwhp/whp numbers with a massive pinch of salt because it can be wrong with 100% confidence and if you dont know...you'll believe it.
I've no doubt within the next decade AI will be able to tune bespoke projects better than most pro tuners but it's really not there yet. I've asked it many things about about the link g4x ecu and so far it's been wrong around 80% of the time and when its wrong its so confidently wrong you'll believe its right. I wouldn't depend on it to make informed decisions. Use it as part of your research and see what fellow owners are achieving in the real world. Also most of the time when owners say i've made whp or rwhp when on dyno..take that with a pinch of salt unless there is some kinda real world result to confirm the dyno power level. For e.g. this is the third time on a different dyno in the UK i've been told its rwhp or whp and when i did a 100-200 acceleration run...its just flywheel HP. There are guys here believing they are running 540hp and 400lb ft at 1.3bar boost but cant even run a 100-200km/h under 10s. If you know you know!
The EFR 8374 you've noted above, I have a real world result that it can run 550hp at the flwheel at 22psi boost on E85 and run into a low 6s 100-200km/h acceleration. Its not doing 550rwhp, if it is..I've yet to see a 5.5s 100-200 acceleration run in the real world on such a setup.
I've no doubt within the next decade AI will be able to tune bespoke projects better than most pro tuners but it's really not there yet. I've asked it many things about about the link g4x ecu and so far it's been wrong around 80% of the time and when its wrong its so confidently wrong you'll believe its right. I wouldn't depend on it to make informed decisions. Use it as part of your research and see what fellow owners are achieving in the real world. Also most of the time when owners say i've made whp or rwhp when on dyno..take that with a pinch of salt unless there is some kinda real world result to confirm the dyno power level. For e.g. this is the third time on a different dyno in the UK i've been told its rwhp or whp and when i did a 100-200 acceleration run...its just flywheel HP. There are guys here believing they are running 540hp and 400lb ft at 1.3bar boost but cant even run a 100-200km/h under 10s. If you know you know!
The EFR 8374 you've noted above, I have a real world result that it can run 550hp at the flwheel at 22psi boost on E85 and run into a low 6s 100-200km/h acceleration. Its not doing 550rwhp, if it is..I've yet to see a 5.5s 100-200 acceleration run in the real world on such a setup.
Last edited by rx7srbad; May 15, 2025 at 10:22 AM.
Agreed. I'm in the adjacent AI security space and at the end of the day, Generative AI is just trying to predict the next word it generates based on what it knows using complex math and probability models. Now, if you fed it say a Haltech tuning document and asked it to give you answers (aka RAG), it would be very accurate. I fed Google NotebookLM a technical architecture doc yesterday at work and had it generate a 30 min podcast and the result was amazing and accurate. Gen AI isn't really good at math because its tyring to reason or guess the result. If I fed it data over and over that said 1+2 = 123242, it would eventually think it was. There are engineering focuse models that are better and number crunching though, but it's not he default model used by OpenAI/ChatGPT.
In this case, I wanted some other input from the smart people about turbos and tuning to see how good (or bad) ChatGPT is about what I asked it. As suspected..it sounds good..but its not 100% right...
In this case, I wanted some other input from the smart people about turbos and tuning to see how good (or bad) ChatGPT is about what I asked it. As suspected..it sounds good..but its not 100% right...
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