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Hey Guys,

I have been around these forums for ages, but never joined so sorry about my first post being so big. I have a 96 gts-t with a rb26 single turbo conversion. The problem is that it is not making the power that I think it should for the money I have spent. Also I have a problem with boost control, my car seems to run stupid boost and make no power. There are talks that the wastegate is to small. The car has made 330rwhp at 22 psi with the following (see below). The car made 210 rwkw at 8pound at 5000 when the motor was being run in so I was expecting big things but at the moment am very disappointed. Am I expecting to much??? Can you see a problem with the build. What would you guys expect the car to make. RNZ11s I raced you when you had the 30/40 setup you might remember my car???

Rb26

Garret 30/40 700hp ball bearing turbo

Port and polish – JHH

Cam gears

Boshe 044

Sard 700cc injectors

Wisco forged pistons – Teflon coated

Shot peened and linished rods arp bolts

HKS Intercooler all piping hpc coated

Turbomsmart pro gate 42 m

Turbosmart super sonic valve

Standard plenum

Halteck ek6

Boost control is just a t-piece.

Thanks for you help!!!

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ur wastegate seems fine

but things to do would be

1. get a better boost controller or even wastegate controller

2. get a decent tune

with these to things - mainly the 2nd one u should c it close to 300rwkw easy

It might help if you could post a dyno readout. I'm no real expert with your particular set up but an RB26 with those mods...wow! I'd be expecting alot more too. Just wondering about the ECU & tune?? Does it run MAP or AFM's? Maybe this calls for Doughboy or SydneyKid....ring ring, brrrr, ring ring :rofl:

Boost control is just a t-piece.

What the......................?

Clearly you have spent buckets on a tough rebuild so how could you possibly overlook the boost controller?

1. Get a REAL boost controller

2. Get another tuner.

The problems is I am sick of spending money to recieve the results I am getting. My thinking is spend 700 bucks to find out that it is not a boost problem, does that make sense. So many people have had a look and don't know what is going on. Getting over it.

As a guide, My GTR made 360rwhp or 270rwkw with Stock Motor, Apexi PFC, Cam Gears, Boost @ 15psi, & exhaust. Running stock fuel pump...etc etc wish I could help, love to see your end result sounds like an animal.

Ditto - 33GTR, same mods minus the PFC and same power

help: You need a good tuner

Hmm, seems wierd. I would be looking at your exhaust side, as already mentioned. If you are winding more boost in, with little return, it sounds like back pressure to me, or the turbo is well out of its efficiency range. If its a 700hp turbo, I think I would be correct in assuming the turbine AR is reasonably large, so I doubt any restriction is there.

try dropping the exhaust and take the car for a quick squirt (or better still put it on the dyno) - takes only a few minutes to drop. You do run a 'racing' cat dont you?

I had a nismo exhaust, that started choking the car at around 285rwkw, changed to a super dragger and made boost alot earlier, and got alot more top end - now making well over 300rwkw (on a 480hp turbo:) sorry just had to throw that one in:p)

take a good close look at your bov too - I have seen those turbosmart supersonics leak like a sieve, try putting you hand over the oulet whilst at idle. If it is leaking, you may still be making boost, but the car will be alot more lethargic off boost, and ramp slower onto boost instead of hitting hard.

Steve,

If "racing" is hollow then answer is yes. Then only reason I changed valves is cause apparently the apexi one I had was leaking to. Valves are annoying to say the least. I am not so much winding more boost in it just does what it wants, we got it a bit lower 18 pound and moved some of the solinoids for the haltec as my mechanic thought they may be fighting the standard ones for a signal. The car felt a little stronger with less boost. I will try and get a graph sent the guy who tuned the car is supposed to be looking after me cause I did some work for his so I will see what I can get. Thanks for telling me that my car makes crap power when I sought it out you will be the first to see the dyno graph :)

The problems is I am sick of spending money to recieve the results I am getting. My thinking is spend 700 bucks to find out that it is not a boost problem, does that make sense.

but that 700 you probably are well advised to spent IMO.

a good controller is probably one of the most important parts.

Aside from that... what AR is your Ex housing?

I find it pretty hard to believe this is caused by a boost controller

I was asking about your exhaust to get a gauge of what manifod / turbine housing you were using. Also with your ECU how much timing are you giving it throughout the maps? Is it pinging? A car isnt gonna make any power with 5 billion pound boost but **** all timing.

Need more details.

something doesn't seems right there could be anything from a blocked fuel filter to crappy mappings, Things like these take time especially in a conversion when all things are removed and the refitted in best possible way.

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