BorgWarner EFR 8374 IWG Dyno Results
01-19-18, 11:34 AM
#277
I know this is a super tough choice for a 2 rotor- EFR 7670 or EFR 8374.
Both turbos can make ~300ftlbs torque at 3,000rpm and 16psi boost on the 2 rotor so you have to decide if making a bit more peak power (8374) or having that 300ftlbs available some thousandths of a second sooner after pressing the gas (7670) is more of a priority.
If making more than ~300ftlbs torque at 3,000rpm is the priority you might want to look at even smaller turbos like EFR 7163 or a bigger engine.
Both turbos can make ~300ftlbs torque at 3,000rpm and 16psi boost on the 2 rotor so you have to decide if making a bit more peak power (8374) or having that 300ftlbs available some thousandths of a second sooner after pressing the gas (7670) is more of a priority.
If making more than ~300ftlbs torque at 3,000rpm is the priority you might want to look at even smaller turbos like EFR 7163 or a bigger engine.
I still want to install a 7670 on a stock port FD and pettit ECU. I haven't driven a FD with a stand alone ecu yet that is remotely close to the same drivability as a stcok ECU FD. I think the 7670 on 12-14lbs would be perfect for a daily driver FD.
01-19-18, 12:20 PM
#278
I still want to install a 7670 on a stock port FD and pettit ECU. I haven't driven a FD with a stand alone ecu yet that is remotely close to the same drivability as a stcok ECU FD. I think the 7670 on 12-14lbs would be perfect for a daily driver FD.
The Pettit ECU does not increase the stock injector size, it might increase max duty cycle allowed. Limited limits boost at 14.7psi and Unlimited has no over-boost fuel cut.
The issue I had with my EFR 7670 on my FC was with 720cc primary and 1600cc 2ndary injectors and a Bosch '044 I had to limit low rpm boost because it was maxing the injectors out ~3,500rpm if I boosted much over 26psi.
You should be able to do ~340-380rwhp at 14.7psi on the EFR 7670 so if you made a restrictive exhaust and or intake to limit it to 340rwhp you might be OK on stock fuel system with the Pettit Limited ECU with the EFR 7670
But at 340rwhp I think the EFR 7163 would be a better turbo.
"Nice" thing about the twins is you have to work to open all the stock bottlenecks to flow get them flowing above what the stock fuel system can provide (~300-350rwhp at the hp peak) and work really hard to get them to the 400rwhp level. With the 7670 its just a matter of boost- so much easier to do that by accident.
01-19-18, 12:27 PM
#279
the switch to the EFR. Its all its cracked up to be.
On the Evo the Hot Version crew tested with EFR 7670 they were gushing about the torque it had (and it was fast).
01-19-18, 10:56 PM
#281
Just basing it off my own experience with my old 60-1 and EFR 7670 (same dimension compressors).
I did 340rwhp at 10psi creeping to almost 11psi on my old 60-1. It did 380rhwp at 14psi and ran out of compressor flow around 16psi boost maxing at 385rhwp.
My 7670 did 345rwhp on wastegate springs which was 12psi dropping to ~9psi at peak hp.
But obviously, my set-ups weren't junk just thrown together, I had fettled with each and every piece put on the car to optimize flow stock or aftermarket.
I did 340rwhp at 10psi creeping to almost 11psi on my old 60-1. It did 380rhwp at 14psi and ran out of compressor flow around 16psi boost maxing at 385rhwp.
My 7670 did 345rwhp on wastegate springs which was 12psi dropping to ~9psi at peak hp.
But obviously, my set-ups weren't junk just thrown together, I had fettled with each and every piece put on the car to optimize flow stock or aftermarket.
01-28-18, 12:53 PM
#282
"Elusive, not deceptive!”
In regard to response. The only thing you should worry about is tuning the cells you have never been in before!
When you nail the 8374 the trace goes straight down to full boost.... ( I use 18 psi)
see attached
When you nail the 8374 the trace goes straight down to full boost.... ( I use 18 psi)
see attached
01-28-18, 02:11 PM
#283
Originally Posted by BLUE TII 
You should be able to do ~340-380rwhp at 14.7psi on the EFR 7670 so if you made a restrictive exhaust and or intake to limit it to 340rwhp you might be OK on stock fuel system with the Pettit Limited ECU with the EFR 7670
You should be able to do ~340-380rwhp at 14.7psi on the EFR 7670 so if you made a restrictive exhaust and or intake to limit it to 340rwhp you might be OK on stock fuel system with the Pettit Limited ECU with the EFR 7670
Narfle
I think those numbers are very optimistic, regardless of ecu.
I think those numbers are very optimistic, regardless of ecu.
Here is a thread from IR Performance 378rwhp at 13.8psi boost with catalytic converter.
https://www.rx7club.com/ir-performan...sults-1122815/
01-29-18, 12:16 PM
#287
Interesting that the half bridge on e85 is making more power with less boost.
That is normal. The more an engine can flow air into it the lower the boost will be for a given compressor CFM.
Not just the engine ports, but everything between the air filter and tailpipe to a greater or lesser degree.
04-19-18, 04:09 AM
#288
Does anyone have any experience with minimum boost pressure achievable with an 8374, with a 3.5 inch exhaust (with cat) on stock ports?
Trying to understand whether a flex fuel setup is possible whilst running a 3.5inch exhaust.
Trying to understand whether a flex fuel setup is possible whilst running a 3.5inch exhaust.
04-19-18, 09:24 AM
#289
I don't know anyone who has tried that exact combo, but with a full 3" exhaust and high flow cat people have held 10 lbs to redline( both on dyno and street).
I would think you would be fine, generally within the range that most people accept as the limit for pump gas( 15psi ish).
You can run higher power levels on pump gas FYI, engine just needs to be tuned real rich( low 10s).
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Warrior777 (10-12-18)
04-23-18, 07:18 AM
#291
When you say 3.5" exhaust, are we talking a 3.5" cat, and 3.5" catback also?
I don't know anyone who has tried that exact combo, but with a full 3" exhaust and high flow cat people have held 10 lbs to redline( both on dyno and street).
I would think you would be fine, generally within the range that most people accept as the limit for pump gas( 15psi ish).
You can run higher power levels on pump gas FYI, engine just needs to be tuned real rich( low 10s).
I don't know anyone who has tried that exact combo, but with a full 3" exhaust and high flow cat people have held 10 lbs to redline( both on dyno and street).
I would think you would be fine, generally within the range that most people accept as the limit for pump gas( 15psi ish).
You can run higher power levels on pump gas FYI, engine just needs to be tuned real rich( low 10s).
Also compared to a stock twin turbo how is the response? I like how i can start spinning the rears from 2.5k rpms.
I want to go ahead and start ordering stuff for a 8374 build but here in Greece nobody has done it so there's no car I can test drive to see how it actually feels on the road.
I enjoy the car on the street so I love how the twins pull strong down low in the rpm range.
04-23-18, 10:09 AM
#292
What power levels should you expect with this setup on a street ported car with an Adaptronic Select ecu, a vmount, a full 3" exhasust and around 15psi on european pump gas (100 octane)?
Also compared to a stock twin turbo how is the response? I like how i can start spinning the rears from 2.5k rpms.
I want to go ahead and start ordering stuff for a 8374 build but here in Greece nobody has done it so there's no car I can test drive to see how it actually feels on the road.
I enjoy the car on the street so I love how the twins pull strong down low in the rpm range.
Also compared to a stock twin turbo how is the response? I like how i can start spinning the rears from 2.5k rpms.
I want to go ahead and start ordering stuff for a 8374 build but here in Greece nobody has done it so there's no car I can test drive to see how it actually feels on the road.
I enjoy the car on the street so I love how the twins pull strong down low in the rpm range.
Depending up how your dyno reads anywhere from 380 to 450rwhp.
On pump gas with a 3" exhaust I find the response to be about the same as the twin sequentially. If you move up to a 3.5" exhaust, and E85 then its faster than the twins on a standard 3" exhaust. Both combinations have much better top end compared to the stock twins, and obviously no dip in the powerband. I've never seen anyone say they don't love the powerband from this turbo system.
04-24-18, 05:44 PM
#293
When you say 3.5" exhaust, are we talking a 3.5" cat, and 3.5" catback also?
I don't know anyone who has tried that exact combo, but with a full 3" exhaust and high flow cat people have held 10 lbs to redline( both on dyno and street).
I would think you would be fine, generally within the range that most people accept as the limit for pump gas( 15psi ish).
You can run higher power levels on pump gas FYI, engine just needs to be tuned real rich( low 10s).
I don't know anyone who has tried that exact combo, but with a full 3" exhaust and high flow cat people have held 10 lbs to redline( both on dyno and street).
I would think you would be fine, generally within the range that most people accept as the limit for pump gas( 15psi ish).
You can run higher power levels on pump gas FYI, engine just needs to be tuned real rich( low 10s).
04-24-18, 09:58 PM
#294
The above results are the same on an HKS cast manifold too. As soon as you put a big free flowing exhaust on it, you start creeping a lot more in the higher RPMs.
04-25-18, 06:59 AM
#295
There is a 7670 IWG .92 a/r available for sale in my area for 800 euros. That is really cheap the guy says the turbo has only done 5-6 pulls on 20 psi.
However from what I read here, I think I prefer to wait, save up and get the 8374.
I just HOPE what Turblown's saying about the 8374 spooling as quick as the stock twins sequentially is true and achievable.
However from what I read here, I think I prefer to wait, save up and get the 8374.
I just HOPE what Turblown's saying about the 8374 spooling as quick as the stock twins sequentially is true and achievable.
08-30-18, 11:04 AM
#297
So is there any special modifications that are required to get the quick spooling boost by 3000rpm with a 8374 setup? For instance my plan is to use a adpatronic pnp ECU with 3 inch exhaust (I have a 3 inch BHR midpipe and 3inch exoticspeed cat back-this is a Rx8 REW swap) and top mount turbo set up. I'm shooting for the quick spool and anywhere from 350-400whp on pump gas with water injection, also planning on using air to water intercooler.
08-30-18, 11:43 AM
#298
Exhaust Manifold Leak
logic sense would assume that the smaller the manifold volume (cast, not top mount), the better the spool would be. but maybe some have hands-on experience with both setups.
08-30-18, 01:15 PM
#299
^^
My experience with stock and street port rotaries with turbos is the smaller volume and diameter the exhaust manifold and turbo exhaust housing and the larger the downpipe the faster the response of the same turbo.
I believe this holds true until you get to drag set-ups with really big laggy turbos combined with engines with huge overlap. Then more volume, length and diameter in the exhaust manifold leading to the turbo can allow for more exhaust expansion pre-turbo where the intake/gas sucked into the exhaust on port overlap can expand and power the turbo. I'm talking T6 flanged turbos sized for 800+ rwhp here, nothing normal people think of street-ing.
If there is any way you can get a 3.5" or 4" downpipe in the RX-8 with the turbo do it.
The front mount placement of the turbo in the RX-8 is already terrible for spool in most turbo kits since you have a 90 degree bend in the downpipe right off the turbo.
If you have to use this style kit, try to find a 90 bend for the downpipe right off the turbo with as large a radius as will fit in the car as well- don't settle for these tight CLR bends most people use for ease of fabrication.
Try to use the style kit where the turbo is angled 45 deg in front of the engine for a better downpipe flow. Like the Turblown EFR kit.
My experience with stock and street port rotaries with turbos is the smaller volume and diameter the exhaust manifold and turbo exhaust housing and the larger the downpipe the faster the response of the same turbo.
I believe this holds true until you get to drag set-ups with really big laggy turbos combined with engines with huge overlap. Then more volume, length and diameter in the exhaust manifold leading to the turbo can allow for more exhaust expansion pre-turbo where the intake/gas sucked into the exhaust on port overlap can expand and power the turbo. I'm talking T6 flanged turbos sized for 800+ rwhp here, nothing normal people think of street-ing.
If there is any way you can get a 3.5" or 4" downpipe in the RX-8 with the turbo do it.
The front mount placement of the turbo in the RX-8 is already terrible for spool in most turbo kits since you have a 90 degree bend in the downpipe right off the turbo.
If you have to use this style kit, try to find a 90 bend for the downpipe right off the turbo with as large a radius as will fit in the car as well- don't settle for these tight CLR bends most people use for ease of fabrication.
Try to use the style kit where the turbo is angled 45 deg in front of the engine for a better downpipe flow. Like the Turblown EFR kit.
Last edited by BLUE TII; 08-30-18 at 01:22 PM.
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Warrior777 (10-12-18)
08-31-18, 10:26 AM
#300
thank you for the quick reply.
I understand. Here is a picture of what I was planing as far as turbo placement. I will be relocating the battery and the ECU if needed to allow for more room. I will just have to see what fits where and what is better. I have also gleaned from reading that you have to run higher boost pressures with the larger free flowing exhaust. I'm all new to this so it seems complicated.
I understand. Here is a picture of what I was planing as far as turbo placement. I will be relocating the battery and the ECU if needed to allow for more room. I will just have to see what fits where and what is better. I have also gleaned from reading that you have to run higher boost pressures with the larger free flowing exhaust. I'm all new to this so it seems complicated.
Last edited by Warrior777; 08-31-18 at 12:30 PM.