Need Help Guys!

[Yo-Yo]

Hey skyliners,

Recently had a power fc & boost controller installed on my car & for some reason the power delivery stops once the car reaches the 180kw mark.

My tuner said for my mods my car should've easily hit the 200kw+ mark. I'm taking it back soon so he can see what might be causing the restriction but I thought maybe some of you might be able to shed some light or give any suggestions or tips.

Car is an R34 GT-t 1998 coupe.

My car still has the stock turbo so hi boost is set to 12 psi, lo boost at 9psi.

My mods:

- Split 3" engine pipe bought from powerplay imports in sydney

- 3" JIC magic dump pipe

- 3" hi flow X-force cat bought from Just Jap

- HKS hi-power silent cat-back xzorst

- Apexi Power FC

- Greddy Profec B spec II

- HKS mushroom pod with CAI & modified factory snorkel

- Hybrid GT spec intercooler

- HKS SSQV type bov plumback

- Nismo fuel pump

- Splitfire coilpacks

The car itself is running well is serviced regularly.

Hope somebody out there can help

thanks in advance people

[The Dan]

nope, 190rwkw sounds on the money. Essentially, all the mods you have are exhaust, intercooler, powerFc and boost controller.

I would expect 170rwkw for same without PowerFC and have seen results of three of such.

[cheez]

sounds about right mate, only thing that concerns me is the fact that boost goes from 12psi and then tales off to less than 10psi.

other than that, i cant see much wrong.

[Yo-Yo]

Fair enough, thanks for that guys

Cheez: any reason you might think the boost tails off? Is it a common thing for the stock turbo to do this?

[cln]

its the stock turbs.. fullboost by 3k dies out by 4

[R34 GTT]

yer mate i got roughly the same mods as you and i got 210rwkw @11psi so yer i dont know it may be in the tune of the power fc.

[Abo Bob]

It's the boost controller. It should be able to hold 12 psi to the end and it's not. The AFR's are too rich up high as well but fixing that will only get you another 5rwkw or so. If you really can't get the boost controller to hold the 12 psi then you might have to look at putting some preload on the actuator or replacing it with an adjustable one.

[Yo-Yo]

It's the boost controller. It should be able to hold 12 psi to the end and it's not. The AFR's are too rich up high as well but fixing that will only get you another 5rwkw or so. If you really can't get the boost controller to hold the 12 psi then you might have to look at putting some preload on the actuator or replacing it with an adjustable one.

Is that a common occurance with the Greddy Profec B specII?

would getting another type of controller fix the problem or can it simply be fixed at the tuners?

Thanks again for all the replies guys!

[(B1) MR_fanny]

i got 199kw with 11psi stock ecu, exhaust cam gear, exhaust, intake, and 34 smic which surprised the crap outta me.

dunno about the profec but with the blitz one i got if you set the gain too high it over boosts past the limit and retards the ratio to settle it back down. once you get the combo of gain and ratio right it holds boost fine. maybe check if your ebc has those parameters to play with.

[limpus]

One more thing worth trying which was the case for me...i had an x-force "hi flow" cat which was shit...i changed it to a 3" metalcat and got it retuned...my tuner managed to dial in more timing and peak power rose by 12rwkw...with heaps more in the midrange too...

[r33cruiser]

can anyone say

RICH

[R33GOD]

which is what i was about to say. its running rich in the higher rpm which is why you made the power u did. If you had 12.0/1 top end which is still stoichometric id say you would pick up another 5-10 rwk.

but it is very safe the way it is also

[GTR 94]

can i jus say somthing, but has anyone thought that not everyones dyno will read the same, some times there can be a 20 kw difference so just take that into consideration

[Yo-Yo]

One more thing worth trying which was the case for me...i had an x-force "hi flow" cat which was shit...i changed it to a 3" metalcat and got it retuned...my tuner managed to dial in more timing and peak power rose by 12rwkw...with heaps more in the midrange too...

I've got that aswell, so you reckon metalcat is the way to go... cheers

[limpus]

Quite a few decent cats in the market...a 3-4" metalcat or catco one should do fine...

[silva33]

Just gut your cat.. I tested hiflow cats then put on a gutted cat and would never go back to having a cat in my car.

[Cubes]

Gutting the cat is silly as it leaves a large void where the gases expand then squeeze back down which introduces turbulence as a result back pressure. All though still better than having a restrictive ceramic cat in place its not as good as a straight pipe. If your going to do it do it properly and weld a pipe through the guts of the cat.

BUT..

Metalcat FTW