Thanks for your answer.

Im running 83mm wheel and 1.10 A/R housing and im not using a restrictor on the oil inlet.

Switch out to the largest valve seat! Run the preload adjuster all the way out then about 4 turns in. Run the boost line direct to port c and see how well the boost holds. Port C should net you 18psi. If all is well hook to C&A and you should be at ~22psi. Ditch the boost controller for awhile.

100 miles what? how much of a restriction was used ? what size jet? must have been starved of oil. thats nuts

nice #'s gus, what kind of porting are you running again?

Thanks!
im running a big street!

I removed my ic pipes today and they smelled like vodka :suitdance

soon im back on track... :)

hows the condition of the turbo?

Is the housing scored up?
How much oil pressure does your motor have?

The housing is allright, the engine sees about 36psi at idle. could a popped silicone hose cause the problem, over-rev? :wallbash:

Over-rev is definitely not good... Although you should be able to withstand a few before failure..

I talked to jz at forced inductions and he told me they had a couple of failures because of over reving. He offered me a cheap repair so im not that worried.

Just got better clamps and did some welding on my intercooler piping so tomorrow i'm back at the dyno.

Is the engine using larger studs or have any extra dowels?

how did you get an over rev from intercooler pipes popping off?

And a turbo getting damaged from an overrev? Thats crap.


Turbo is simply faulty.
IT SHOULD BE COVERED UNDER WARRANTY. Dont give them excuses for them to tell you that they wont be fixing it cause you overreved it, any reason not to honour warranty.

Ive had intercooler hoses blow off at over 40psi and nothing happens to the turbo.

the engine has got 5 extra dowels, stock studs.

Good to know, thanks!

your boost drop off in the high rpm is probably due to the 3" exhaust. I have a feeling that once you upgrade to 4" exhaust, you might pick up 30-40hp in the 7000+ rpm area.

I'm building a car with the EXACT same turbo on a 20B, and I'm running a 5" -> 4" -> dual 3" exhaust. I'm hoping to get 500whp at 10 psi or so, and 650whp at 15 psi.

Doubt the 3inch exhaust is that much of a problem. the bottle neck starts before the exhaust. remove the exhaust all together and see what happens and then youll know for sure. or make a temp dump tube for the exhaust like the race cars use just to see if it helps.

i believe chohakai is right, 600whp seems to be the limit of a 3inch exhaust.

Did some more pulls today and boost will hold perfectly steady up to 22psi, even if i put the boost controller to 25psi i will have 22psi by redline. We are routing the exhaust out of the dyno room through a big muffler, we did a test removing it and gained 10whp!

I remember i did some tests on my t78 turbo, measured downpipe backpressure and att full power i had 4.5psi of backpressure. I wonder why i never used this information :Wconfused

So, im bringing the car back home and ill start fabricating asap, then back to the dyno :)

I have to say that the turbo is very responsive!!!

Are all of your injectors in the LIM and no longer using the primary injector ports? I ask this because you are using the pfc.

Very nice work with the UIM, how did you create velocity stack part of the plate? English wheel?

First of all thanks for your comment!

Im using both primary and secondary, 6 injectors. The 2x2 secondaries are using the same injector driver, setting the PFC to 3360cc for each secondary port (2x1680), Why so many? the car is running on E85 :icon_tup:

About the velocity stacks you see that they are divided into 4 square pieces welded together (10mm thick plates), they are made in a lathe with a special tool i made to make the right radius.

Yes less then 100. The turbo had a .035 restrictor on it. Not a good thing at all. When it was pulled apart the shaft was blue. Clearly starved badly.

Glad you got the sucker running again. That turbo is tough. Where is full boost coming in?? Also have you measured backpressure before the inlet to the turbo?

Yeah you can see a log on the previous page, i had 28psi backpressure at 22psi boost.

about where full boost is coming in on the street i cannot say, drove the car home but there is snow outside so had no chance to try it out, did some small pulls on the highway and the turbo is there pretty much instantly..

on the rototest we start from 4000rpm and boost is basicly there from the beginning...

Very nice. My buddy just picked one up from the same folks....we got it all bolted up on the car this past Friday night. Car runs awesome and he's only at 24psi. His exhaust like yours is 3". I think we are going to build a 4" exhaust if all possible. Are you planning to stay with the 3"?

Nice! any numbers yet? :)

Im going 4", trying to find some good 4" mufflers... very hard to find here :wallbash:

632rwhp so far. He is going to buy the race cover today to see what kind of difference that makes before the swap to the 4" exhaust.

sweet!! please post the numbers with the race cover when you tried it!

is this with racefuel or e85? 1.10 or 1.32 A/R? i guess that the amount of fuel burned using e85 is causing my 3" to choke?