Max Boost & Fuel Cut questions
11-25-2002, 05:18 PM
#1
Guest
Posts: n/a
Max Boost & Fuel Cut questions
What is the max boost the turbo & motor can handle?
Also, i hit fuel cut & got a cell because i hit 17psi, once the light goes on, what happens?
when i hit cut the other day, i stepped on the gas in 5th and the boost went flyin to almost 20psi! and there wuz no cut!
is this the poor man's way of eliminating
Also, i hit fuel cut & got a cell because i hit 17psi, once the light goes on, what happens?
when i hit cut the other day, i stepped on the gas in 5th and the boost went flyin to almost 20psi! and there wuz no cut!
is this the poor man's way of eliminating
11-25-2002, 06:17 PM
#4
Registered User
Join Date: Nov 2002
Location: Plattsburgh, NY
Posts: 192
Originally posted by Hassassin
well ur not so shutup, but thanks for the useful info!!!!!!!!
well ur not so shutup, but thanks for the useful info!!!!!!!!
What will happen is the ECU will shut down the fuel pump for a fraction of a second but you will feel it.
11-25-2002, 06:59 PM
#5
Guest
Posts: n/a
Saying that the stock turbo can put out 19psi without problems is not exactly the whole story.
From the compressor maps I have seen, and my own experience I don't think that the turbo would too efficient past 16psi. This has been covered countless times in FFI etc.
Hassasin if you want to run more boost or run boost at an psi higher than 16psi on the stock turbo then you should probably use race gas just to be safe since the air would be much hotter at those pressures, and the risk of detonation, or pre ignition etc. is increases. If you want to run higher boost pressures all together on a daily basis I would suggest buying a bigger turbo, where you could run 14.5psi but pump more air(cooler air too) into the engine than the stock turbo at say 16psi..
I have had the turbo spike up to 20psi by "accident" as well in 5th gear without fuel cut, but would hold it at WOT long enough to initiate fuel cut I suppose. In 3rd gear I have seen fuel cut kick in around 18psi a few different times. I have can stay at 17psi no problem without cut however on my setup.
As for your question as to how much boost the motor itself can "take", that answer will be based on what type of fuel you are using, coupled with how the car is tuned and it's supporting mods(eg. injectors, fuel pump+lines, intercooler/turbo efficiency)
Here is a link comparing different turbos/CFM
https://www.i-club.com/forums/showth...=&threadid=370
Here is a link to TeaguesAuto.com electronics page, here you can find the MRT fuel-cut defender.
http://home.att.net/~teaguesauto/ecuwrx.htm
Paul
From the compressor maps I have seen, and my own experience I don't think that the turbo would too efficient past 16psi. This has been covered countless times in FFI etc.
Hassasin if you want to run more boost or run boost at an psi higher than 16psi on the stock turbo then you should probably use race gas just to be safe since the air would be much hotter at those pressures, and the risk of detonation, or pre ignition etc. is increases. If you want to run higher boost pressures all together on a daily basis I would suggest buying a bigger turbo, where you could run 14.5psi but pump more air(cooler air too) into the engine than the stock turbo at say 16psi..
I have had the turbo spike up to 20psi by "accident" as well in 5th gear without fuel cut, but would hold it at WOT long enough to initiate fuel cut I suppose. In 3rd gear I have seen fuel cut kick in around 18psi a few different times. I have can stay at 17psi no problem without cut however on my setup.
As for your question as to how much boost the motor itself can "take", that answer will be based on what type of fuel you are using, coupled with how the car is tuned and it's supporting mods(eg. injectors, fuel pump+lines, intercooler/turbo efficiency)
Here is a link comparing different turbos/CFM
https://www.i-club.com/forums/showth...=&threadid=370
Here is a link to TeaguesAuto.com electronics page, here you can find the MRT fuel-cut defender.
http://home.att.net/~teaguesauto/ecuwrx.htm
Paul
Last edited by PaulRex; 11-25-2002 at 07:04 PM.
11-25-2002, 08:57 PM
#6
Guest
Posts: n/a
Hey Paul,
Ive run 20 lbs and had no fuel cut. I think that once you get that high on boost, the turbo gets so hot that your actually losing power. It's been explained to me better before but its late, Im going to bed. Ill post tomorrow when my brain is on again.
Pete
Ive run 20 lbs and had no fuel cut. I think that once you get that high on boost, the turbo gets so hot that your actually losing power. It's been explained to me better before but its late, Im going to bed. Ill post tomorrow when my brain is on again.
Pete
11-25-2002, 11:33 PM
#7
Registered User
Join Date: Nov 2002
Location: NY
Posts: 275
Car Info: o2 duburu arr exu
if you just peak at 17psi you shouldnt be getting a fuel cut. you will however if you hold 17psi. my stock turbo has actually spiked to 1.5bar without a fuel cut (happened when i first put in my headers and mbc).
don't worry about the cel. assuming you lowered your boost to >17#, it'll clear after you drive for a couple days. try keeping boost at around 16# and see what happens. if it doesnt clear after a while, you may want to pull the code to see if anything else caused it besides the overboost condition.
don't worry about the cel. assuming you lowered your boost to >17#, it'll clear after you drive for a couple days. try keeping boost at around 16# and see what happens. if it doesnt clear after a while, you may want to pull the code to see if anything else caused it besides the overboost condition.
Thread
Thread Starter
Forum
Replies
Last Post
silver ghost
Engine/Power - EJ25T (STI and 2006+ WRX)
2
12-26-2004 07:11 PM
wrxraybrand
Aftermarket Forced Induction - Turboed factory NA engines
1
08-09-2003 08:48 PM
Hassassin
Engine/Power - EJ20T (pre-2006 WRX and JDM)
12
11-26-2002 01:04 PM
