Ok so I got my car back today and Chris came over to get the car back on the road. Everything seems fine and the tune seems to be holding pretty well BUT I am unable to go over 8psi with my .8BAR spring (11psi). We tried removing the s-pipe, bypassing the boost controller, and even removing the wastegate to see if it was broken. After every run we found that the psi was exactly the same under any situation. The ONLY thing that we found to be a problem was the WG had a pinched orange gasket (diaphragm I assume). We unpinched the gasket and tried again but it was at the same boost level.

I am running a big red spring (.8BAR) on a Tial 38mm WG using an open dump tube. When I had the same wg with a 3.6psi spring I ran 3.6 psi... Also with the boost controller on I can go to higher boost levels. We have done a boost leak test and plugged all the holes.

 

sorry there but the red spring is 5.8psi

 

http://tialsport.com/prod_wg_38.htm

On the right side click on the Springs and open the PDF. I got a BIG red spring not a SMALL red spring.

 

get a 8 psi spring and get a turbosmart boost tee... i had same problem... needed a boost controler

 

http://www.assaultech.com/turbosmart...e/g-55952.aspx

buy this then remover the ball and spring out of it so u don't over boost... then start upping the boost and tuneing

 

take off the air filter and see if you hit full boost. start there.

 

or u mayb have a exhaust or vaccum leak under pressure?

 

also if you have access to another boost gauge or any dataloging capabilities, see if you get different readings.

 

I have a boost controller and I can pass 8psi on the boost controller.

I checked vacuum and boost and no leaks. Also there is no sign of an exhaust leak. We tried even removing the exhaust and got the same results.

Sounds like a plan.

Yea we tried with the FIC and with the AEM Truboost gauge. Same readings.

 

couple of things we didnt do, we didnt blow any air through the wastegate to make sure the sealing ring is doing its job, i didnt notice any light through it so dont think thats it. we didnt swap out wastegates or springs. we also havnt tested the fic vac source or the boost gauge vac source. Kyle did have a 4psi spring in there when he first got the tial and it did every bit of the 4psi. perhaps the spring was mislabeled from the factory (just an idea).

so what we have done so far is

1.boost leak test
2.disconnected the exhaust from the downpipe just incase the stock s-pipe was choking the exhaust flow.
3.checked for any sign of leaking from manifold and turbo
4.I checked shaft play on the turbo just to see how it has been doing since the rebuild
5.disconnected the ebc and compleatly removed the cylanoid from the vac lines, ran vac from turbo to wastegate.

boost doesnt creep or spike. its fairly steady.

 

made 6runs trying different things listed above and datalogged it all, fic and truboost match. i would first think that the vac source is leaking but we did a boost leak test already.

 

..

 

back when i first got my zpi kit, the intake pipe was too long and was pushing into the cone filter, thus choking off the turbo. it wouldnt make over 6 psi.

 

hmmmm...didnt check that and i should have but it didnt cross my mind...Kyle go outside and check that...lol

 

bite me

 

^^ I'm gonna try that extra intake pipe to see if it works any better. The filter is unobstructed though and has a large area from which to gather.

 

what he is talking about is perhaps you pushed the filter onto the pipe too far...just take the filter off.

 

^ I will the gf is home right now so it will have to wait until before skewl tomorrow.

 

taking off the filter or intake might help but i dont think that is the cause.. I used to route my intake down the fender (like CAIs) and i still creep boost, all i felt was a bit of lag.. but then i have a gt30, the zpi was way smaller turbo. Are you using a dump tube?

 

thats the thing though boost is steady...nothing really goofy going on except for the fact that he ordered a tial wastegate with a 11.6psi spring (large red) from p-tuning and got a 5.8psi spring instead (small red) so he had to order another spring from them. I think it was the 5.8 they sent, i remember it was a small spring...Hey kyle what spring did they send you with the tial? was it small red or small yellow?