On a cossie engine is there anyway the engine itself would restrict the boost level????





john

 

think a p8 ecu has a restrictor if summits wrong with the engine/sensor, limits it to 4k i think

 

I dont mean electrics i mean just the engine itself, mechanics.




john

 

revs and boost is cut at 7k revs i think on standard management

 

No!!!

Basicly iv changed the engine in my cossie to low comp, T34, greys etc now i cant get anymore than 18psi out of the engine and thats nearly at rev limit, i have changed actuator and checked for ir leaks etc.

Before i changed engine it was running stage 3 at 26psi.

I have also looped turbo with a bleed vlave and still only got 20psi at high revs, it doesnt start boosting til 3-3500rpm!!


any info apprerciated please guys





john

 

silly question but is the turbo housing/ exhaust all nice and tight? bit out of my range mate

 

No prload on actuator (min 3mm) or a Cracked wastegate is very likely, after ruling out simple things like leaking dump valves and pipes etc of course.

 

Have put preload on actuator, taken off dumpvalve. I have fitted new pipes from actuator and turbo to amal, iv even changed amal valve.

i hope its not cracked wastegate as bought the turbo off someone on this board and he said had only done 1000 miles!!!




john

 

thinkin again john, stu had this prob with mine and it turned out to be the join where the 2 bits of the 2wd exhaust manifold join, 2 bolts had fallen out and the manifold was flexing under load and leaking like a twat, juat a thought

 

Oh right, i have fitted a 2wd exhaust manifold to my 4x4 but all nuts and bolts are tight as not long ago fitted it all!!




john

 

mine came slack on the drive to stu's if you havnt used the correct bolts coz they apparently are special ones or summit they just come loose quick as fook

 

john out of interest how did your 2wd manifold fit with it being 4x4 as the exhaust woiuldnt go on my turbo when i did it and i had to change it back think i need a bit weldin on the exhaust to make it higher

 

the bolts are proper ones.

Had to disconnect exhaust from down pipe the refit, its tight under gearbox but ok.

I have mongoose system.



john

 

how about sending my parts?

 

Bump





john

 

try wire'in up the actuator, and in say 3rd /4th gear bring boost in usin the brakes and throttle, (be carefull, dont cook the brakes, or do it for more 5-10 seconds, and dont go past 25/30 psi boost)

if even at 4.5 k rpm still not hitting proper boost then, could have

blocked zorst,
crack in turbo, or mani leak,
air leak, have you pressure tested whole system to 30 psi?
cam, or cam timin problem

 

actuator fooked?