What Would Cause More Boost?

[jamie curran]

hey guys, my partner just bought an R32 GTST, its boosting to 13-14psi with a standard actuator and im not sure what's causing it. Mods to follow;

Aftermarket side mount intercooler,

Turbo back exhaust,

HKS ignition,

Bosch 044 fuel pump with surge tank in boot,

and a few other little things not really enhancing performance.

any ideas would be apprieciated.

thanks

Jamie Curran

[Silvia GTR]

Does it have a boost T or electronic boost controller in cabin?

[Simon-S14]

if no boost controller then it could have a leak in the hose going to the actuator

[Ant97GTR]

Check your vacuum hoses for leaks...

[jamie curran]

@Silvia GTR

Nah mate standard actuator, no boost T and no ebc in cabin that i cant see

@Simon-S14

Ok sweet, i didnt realise leaks could cause more boost.

@ant97GTR

once again, didnt realise a vacuum leak could cause more boost, thought it would cause a loss of boost.

Edited June 27, 2011 by jamie curran

[bubba]

A leak in the cooler pipes will cause a loss of boost.

A leak in the vacuum hose going to the actuator will cause an increase in boost because the pressure is bleeding off before it gets to the actuator, thus requiring even more pressure before the leak to move the actuator.

[jamie curran]

@bubba

sweet as, cheers for explaining it mate

[The Mafia]

lol, just out of curiousity - why did you get a surge tank, massive fuel pump, and HKS ignition if the rest of the car is stock? (Seems like it from your post?)

[jamie curran]

haha i was thinking the same thing - we bought the car how it is lol

[KiwiRS4T]

Maybe it had a massive turbo injectors etc etc and he returned it to stock except for the fuel system?!

[jamie curran]

@KiwiRS4Ti have no idea..... he is a metal fabricator, i think he just got the pump because he made the surge tank himself and wanted to use it. (good quality too)

also it may still have big injectors, i havent checked

Edited June 27, 2011 by jamie curran

[Dose Pipe Sutututu]

I would check the hose between the hot pipe & the actuator. Those factory rubber hoses may have cracked as their old, allowing boost to leak causing the boost to "spike". Other than that, there could be a possibility there's an aftermarket actuator, or the rod has been altered.

[jamie curran]

@johnnilicte

thanks for the info

[jamie curran]

hey guys, bit of an update.

i checked all the hoses with soapy water and found a few leaks around the oem bov from where i had it off and on the blitz bov which i soon fixed, only to find that now it just hit max boost faster and sticks flat on 14psi till around 6k revs and starts to deteriorate.

also i had a chat to clint from pro-stroke and he said the spring in the actuator could be cut/different pound rating? is this something that is generally done guys? or possibly the rod or aftermarket actuator as jognnilicte said and i just dont know the difference lol

[jamie curran]

some pics, someone tell me gently if ive totally screwed something up haha

Thanks to Simon-S14 for this mad blocker idea.

White King lid for the plumb blanking plug

NEW BOV!!!! .............well old... but new...

Edited June 28, 2011 by jamie curran

[jamie curran]

ok guys, just went to my local workshop, @johnnilicte, you were right, the actuator rod has been altered. thanks for the help guys, im thinking of making a build thread on the car too.

cheers