i am running 1.8 bar boost but at higher revs its dropping off to 1.5 what can it be what do i check cheers mike
2.1/ sc46 451bhp/ fmic /3 port/ fpr/rcm 3" ehaust /hks bv/ 1997 sti ?been told it could be silecon inlet hose sucking closed?

 

Could be the silicone hose sucking shut or dv leaking.... What air filter are you running?

Banny

 

hks fillter hks dv but tryed aps dv and it was the same

 

mine did that and it was a split in one of the silicone joiners in the fmic pipework

 

what hose is best i think i have a cheap one on

 

I dont think it makes that much difference as it is just to join the metal pipes on the fmic on mine it was behind the front bumper it had been rubbing on the body work and put a split in it you could tell where it was leaking as there was an oil mist around the area where it was.

 

Was it mapped like that to be safe ?

dunx

 

@dunx no mate just keeps droping off starts at 1.8 then goes to 1.5 my map is on the last page of s/c theard

 

Mine used to do that & turned out to be boost controller set up in-correctly ... wasn't wired up to monitor revs & throttle pressure Once wiring was sorted a few tweaks to the unit & all was well.

TX.

PS

Here is mazmikes graph from other thread:

http://i740.photobucket.com/albums/x..._Image0002.jpg

PPS

450hp seems a good result from lowish boost!

 

sorry m8 but what is the boost controller and where is it i have a simtec ecu

 

We'll need one of the technical guru's to reply I guess My car runs an Autronics ECU & a HKS EVC VI boost controller. It wasn't holding the boost flat to the redline ... was peaking at 1.8 then dropping quickly to 1.5. It now peaks at 1.9 & holds 1.8 to the redline.

TX.

 

Thanks for the comments re power for boost, we were quite happy with the outcome and the car goes like stink.
On Mikes car the boost is being controlled through a Prodrive 3 port solenoid and the SimTeks internal boost control. This has rpm dependant settings and has been maxed out at the top end to try and stop the drop. As Mike has mentioned, we suspect that the inexpensive intake hose could be sucking shut at high boost/rpm demands (And this wouldn't be the first time we have seen that), or that excess back pressure in the exhaust could be opening the wastegate.
The intercooler system has recently been checked for leaks and is leak free.


Martyn

 

yes mate well happy with 450hp its not worth spending any more money on it to get more hbp as its a fast car on the road now .just trying to sort out the little things now .as martin said looking to re place the inlet hose now .seen one at scooby clinic

 

If you need a 76mm one, I have lateral performance one for sale