Stock Rb26 + -9S + E85

[Rolls]

sounds like that is almost certainly your issue

[usmair]

16 to 20psi

would love a cheeky 4psi gain on mine

[usmair]

leak is fixed

will be on the dyno again either Friday or Monday to see what the setup is actually capable of!

[N1GTR]

Did this manage to get on the dyno today? Hopefully nothing else went wrong !

[usmair]

tuner was too busy and car didnt go on the dyno

rekons it will go on this arvo... who knows lol

[destrukshn]

what actuators do you have on the -9s?

[usmair]

ok so the leak sorted the boost issue... the turbos are spooling to 25-26 pounds

but the car is still struggling to make power

make 320kw on e85 with 25 pounds :(

Chea said he has trippled checked all the bolt ons and says everything on the outside of the motor is fine

he believes its the head... more specifically the valve springs

peak power right now is at 6300... car just starts struggling to breath and loses power

he's done a compression test on the motor said it was healthy and believes the bottom end is all good

so now we gotta change the head!

any thoughts?? does this problem sound like it would be caused by dodgy valve springs??

I dont want to spend another $2k sorting the head and then finding out there is some other issue thats going to cost me another couple of grand to fix!

[Rolls]

What does the power graph look like? When valves go it is often very bumpy up and down, but even if it is smooth it doesn't rule it out. I've only ever really hard of this happening on rb25s not 26s though. Wait for someone with more experience to reply.

Edited February 1, 2012 by Rolls

[Deano 1]

why change the head if its the springs? Why not just throw a new set of springs though it?

[RB25PWR]

Take it to Unigroup. It sounds like your tuner is guessing, Yavuz does not guess.

[Mick_o]

+1 Yavuz is the Guru!

Take it to Unigroup. It sounds like your tuner is guessing, Yavuz does not guess.

[usmair]

He didn't specifically say to change the head but he is saying its the springs.. he said it might be worthwhile to change the head while you're at it

He said he is very confident that its the springs but as always they can't be 100% certain

I'll put up dyno in a sec

[usmair]

He didn't specifically say to change the head but he is saying its the springs.. he said it might be worthwhile to change the head while you're at it

He said he is very confident that its the springs but as always they can't be 100% certain

I'll put up dyno in a sec

[Rolls]

What benefit would there be in changing the entire head?

[fatz]

strange for a gtr motor to float even at 25 psi

mind you it should be makeing that power at 17psi

mmmmmmmmmm

[usmair]

I'm not sure.. .

How is Yavuz with Haltechs? I guess it doesn't really matter when it comes to diagnosing the problem

[N1GTR]

Take it to Unigroup. It sounds like your tuner is guessing, Yavuz does not guess.

Best post in this thread.

I'd be out the door at "change the head while you're at it".

At least do springs first!

[usmair]

dyno

[usmair]

Best post in this thread.

I'd be out the door at "change the head while you're at it".

At least do springs first!

I might have misinterpreted him

i think he meant due to the cost involved in changing springs... it might be financially better to 'do' the head (if i wanted to) seeing as we're spending $$ on labour regardless

anyway... going to see him on Sat and see whats the next step

but prob will end up getting it to Yavuz for a 2nd opinion

in the meantime, if anyone has any insights feel free to share

[Ryan1200]

What's with the temp probe fault? As we all know mess with the probe and numbers can be greatly effected.