need an answer guys!!
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need an answer guys!!
ok i have a 93 touring...love it! anywayz my power mods are later version pfc(base map),catback,and greddy pulleys?? well im buying a dp and mp soon, it comes in a combo. right now my car is running on 3 catalytic converters(previous owner) the precat, hiflow cat, and a normal cat welded on the catback(apexi n1), if i remove the precat and hiflow and replace with the mp and dp, will i still see some sort of boost creep? keep in mind i will still have 1 stock cat thats been welded on the catback.... thanx
#3
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WTF? THREE cats?!
I'd remove the precat, get an exhaust that isn't cobbled up with a stock cat, and leave the highflo (I assume it's on the midpipe as usual?)... no idea why someone would weld a stock cat onto their catback. Is there even an airpump line going to it? Make sure there's one going to the highflow, and ditch that other nonsense.
I'd remove the precat, get an exhaust that isn't cobbled up with a stock cat, and leave the highflo (I assume it's on the midpipe as usual?)... no idea why someone would weld a stock cat onto their catback. Is there even an airpump line going to it? Make sure there's one going to the highflow, and ditch that other nonsense.
#4
ArmitageFD3S
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Not trying to jack your thread, just want some clarification here. Will a bone stock car with no engine management/fuel overboost with a turbo back exhaust (including highflow cat, NOT a test pipe) and an intake? What needs to be done to prevent running too lean with these starter mods?
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The presence of boost creep with a full exhaust (dp, mp, and cb) seems to vary from case to case. I have seen posts where some report boost creep with a full exhaust while others report none.
I’m currently running intakes, full exhaust, and a Power FC to manage it all. To date I have not seen any kind of boost creep and have been able to manage my boost levels and duty cycles very well by just using the Power FC.
Due to the fact that you are keeping the main cat and are still on the stock intake (from what I read) I would expect you to see elevated boost levels, but most likely not boost creep.
I’m currently running intakes, full exhaust, and a Power FC to manage it all. To date I have not seen any kind of boost creep and have been able to manage my boost levels and duty cycles very well by just using the Power FC.
Due to the fact that you are keeping the main cat and are still on the stock intake (from what I read) I would expect you to see elevated boost levels, but most likely not boost creep.
#7
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Originally Posted by ArmitageGVR4
....Will a bone stock car with no engine management/fuel overboost with a turbo back exhaust (including highflow cat, NOT a test pipe) and an intake? What needs to be done to prevent running too lean with these starter mods?
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#8
ArmitageFD3S
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Originally Posted by C's-7
The presence of boost creep with a full exhaust (dp, mp, and cb) seems to vary from case to case. I have seen posts where some report boost creep with a full exhaust while others report none.
I’m currently running intakes, full exhaust, and a Power FC to manage it all. To date I have not seen any kind of boost creep and have been able to manage my boost levels and duty cycles very well by just using the Power FC.
Due to the fact that you are keeping the main cat and are still on the stock intake (from what I read) I would expect you to see elevated boost levels, but most likely not boost creep.
I’m currently running intakes, full exhaust, and a Power FC to manage it all. To date I have not seen any kind of boost creep and have been able to manage my boost levels and duty cycles very well by just using the Power FC.
Due to the fact that you are keeping the main cat and are still on the stock intake (from what I read) I would expect you to see elevated boost levels, but most likely not boost creep.
#9
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Originally Posted by JD_SMOOTH83
ok i have a 93 touring...love it! anywayz my power mods are later version pfc(base map),catback,and greddy pulleys?? well im buying a dp and mp soon, it comes in a combo. right now my car is running on 3 catalytic converters(previous owner) the precat, hiflow cat, and a normal cat welded on the catback(apexi n1), if i remove the precat and hiflow and replace with the mp and dp, will i still see some sort of boost creep? keep in mind i will still have 1 stock cat thats been welded on the catback.... thanx
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Originally Posted by ArmitageGVR4
I was planning on using an open element air filter with hard intake piping, my PFS catback, a new downpipe, and the factory main cat section. I have stock fueling and stock engine management. No boost control or anything like that either. Do you really need engine management for just an intake/exhaust combo w/factory main cat? Shoudl I be worried about engine longevity with this? Any easier solutions than spending 1000$ on electronics to manage my 100$ in mods or porting my wastegates?
To answer your question, no a fuel management such as the Power FC is not required. It sounds to me like you’re trying to manage your boost levels and modification costs without breaking the bank (This is not a bad thing). In your case and with your mods I would recommend doing a search for a homemade boost controller (home depot boost controller).
If your managing your boost levels properly you should have no worries.
#11
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Originally Posted by ArmitageGVR4
Not trying to jack your thread, just want some clarification here. Will a bone stock car with no engine management/fuel overboost with a turbo back exhaust (including highflow cat, NOT a test pipe) and an intake? What needs to be done to prevent running too lean with these starter mods?
Dave
#12
ArmitageFD3S
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Originally Posted by dgeesaman
You NEED to have a boost gauge hooked up so you can be sure it stays well regulated to 10 or 11psi. If it's creeping higher, you will need to port your wastegate to handle remove the creep problem - but it depends on the car if that is necessary.
Dave
Dave
#13
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Originally Posted by ArmitageGVR4
So the stock ECU can't compensate for additional boost without some sort of engine management huh? Even if you beef up the fueling system? I'm so used to my 4g63 where you can double or triple the factory boost without using any engine management at all and be fine.
Dave
#14
ArmitageFD3S
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Originally Posted by dgeesaman
Yes, it's all in the FAQ. The stock ECU cuts fuel at 12psi, unless it's a spike that happens too quickly for the ECU to react - in which case it goes lean and tends to grenade engines.
Dave
Dave
My experience is that boost controllers are used to fool the OEM wastegate actuator into seeing less pressure than there really is and thereby opening later, increasing max boost. Therefore, how can the boost controller be used to open the wastegate sooner in the FD? Is it something to do with bypassing all the wacky factory vacuum nonsense? I'm assuming that the wastegate is actually sprung pretty low and all that the factory vacuum nonsense actuates boost just like boost controller? Thanks!
#16
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Originally Posted by ArmitageGVR4
Gotcha, I've been doing a bunch of searches/reading on boost creep and it seems that most people agree that a boost controller i necessary in order to limit boox to no more than 10psi regardless of what bolts-ons you have with no engine management.
#17
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Originally Posted by ArmitageGVR4
Gotcha, I've been doing a bunch of searches/reading on boost creep and it seems that most people agree that a boost controller i necessary in order to limit boox to no more than 10psi regardless of what bolts-ons you have with no engine management.
Boost creep happens when the boost controller has the wastegate held wide open, and the flow is still not enough. It won't matter what kind of contoller you have, when the valve is held wide open that's the limit. This is why porting the wastegate fixes it - just a few percent increase in area avoids choked flow.
My experience is that boost controllers are used to fool the OEM wastegate actuator into seeing less pressure than there really is and thereby opening later, increasing max boost. Therefore, how can the boost controller be used to open the wastegate sooner in the FD? Is it something to do with bypassing all the wacky factory vacuum nonsense? I'm assuming that the wastegate is actually sprung pretty low and all that the factory vacuum nonsense actuates boost just like boost controller? Thanks!
The problem is that the stock ecu is an open-loop boost controller using a somewhat special arrangement. The advantage is robustness and safe failure modes (when it breaks it tends to cause no boost, rather than too much). The disadvantage is that it's tuned for a specific flow range - much beyond the stock flow and you'll get poor results. This is why the PFC and other ECU options are limited as boost controllers - the actuator springs and bleed orifices are tuned for a 10psi 255hp car. "Real" manual and electronic boost controllers work independently of the ECU - the downside is that the user must adjust them, but the advantage is that the user can adjust them
Dave
#19
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Originally Posted by ArmitageGVR4
So what I'm hearing is that the only *real* solution to safe operation increased airflow is to upgrade the computer with fuel maps for with increased boost levels or to port the wastegate -- either great expense or great effort. Great.