I seem to be loosing boost at high RPM (when second turbo is suposed to kick in)

My mods
Power FC
HKS Downpipe
PFS SMIC
M2 CAI
Stock Sequentila

I have checked soleinois / TCA etc.

However, I am running very rich at mid to high rpm

Do you think this could be the cause ?

I thank u all in advance

 

check vacuum lines to crv and abv

 

Is the PFC tuned?

 

what boost are you running? the pfc has a rep for not being able to control much more than stock boost very well. when I run 10psi on mine its fine but at 1bar it drops off at high rpm. maybe you could borrow a boost controller?

 

my power fc controls boost perfectly @ 15 psi.

 

I am only running 10 psi

Mahjik: It has been pretuned by Steve Khan as an aproximation, ie. as I live in Greece he has just set it up according to what mods and specifications I told him - it is in no way his fault for the fact that it is not perfectly tuned as it was done on a best efforts basis...and to be honest he has done a pretty fine job considering the distance

In any case, I seem to be running very rich when the second turbo should kick in
I am going to try a map of a friend who has similar mods and see how it goes

 

What do you mean when your second turbo is supposed to kick in ?

Does it kick in or not ? If it doesnt come online then you have some disconnected vacuum hoses or a coupler.

 

I am only making c. 2psi of boost at c. 5500 rpm when I start with 8 to 10psi

 

IMO you should go back to the basics...

Put everything back to stock (well except for the dp, too much of a pain) it should not be to hard since you just have the SMIC, intake, and PFC. what is that an hour's woth of work... don't just put back in your stock ECU since you have other mods and no boost controller to keep you below 10 psi.

See how the car boost, if it boosts fine then you know it's your PFC like others have stated. If not then at least you know it's not your PFC and you can continue the hunt from there.

Edit- I'm assuming you checked for boost leaks and stuff

 

The only way you can be making only 2 psi after the transition is a boost leak -- either through a broken check valve or missing line, or through a split coupler, etc. You say you've checked everything but it's obvious you haven't, as there is still a problem.

The PFC has nothing to do with this problem. Even with completely faulty electronics, if the turbo control system is working, you will still get 7 psi. As with the other current thread, I would check the pre-control routing.

 

If you are only making 2PSI at 5500 rpms, then you have a boost problem.

I would start by looking at:

* Charge control & charge relief systems
* Check valve for the pressure chamber

http://www.autosportracetech.com/RX-...leshooting.htm

Good luck!

 

could your turbo be dropping off in boost pressure at high rpm because the turbo is out of it's effeciency range? I know on other cars with high boost a lot of stock turbos cannot hold pressures like 1.0 bar or higher at redline...

 

Thanks guys
I will let you know how things go

 

check the vacuum lines under the crossover pipe that lead down to the wastegate and prespooler. i had a similar problem and it was those lines. just replace them and zip tie them down if you have some spare hose. mine was a minor crack that i couldn't see until I took the hose off.