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hey guys i purchased a 33 gts-t with gt35 turbo and 38mm waste gate today fmi etc i was wondering what rev range it shud be kicking in at i found that it has alot of high end power but not much down low it doesnt kick in untill 4.5k-5k rpm and i find sometimes its suppose to be running 10psi but u watch the boost gauge and it sits on 10psi but u feel nothing then it will all of a sudden go to 14psi and u will feel it pull hard as any thoughts???

bottom line is thats going to be an extremely laggy turbo on an RB25. So yeah, 4.5-5000rpm is probably about where the fun lies.

However, why the boost is not at the same point seems a bit strange. What are you readaing said boost on?

did you get a dyno printout of when the car was tuned with the GT35? that should tell you when the power should come as well as what psi of boost you should be seeing...

I think the real point here is - take it to a workshop that knows RB performance.

Don't mean this the wrong way but it sounds like you don't really know what you've purchased, or know that much - or you wouldn't be asking.

So take it somewhere and give it to them for a SOLID looking over. The fact it sounds like it has all sorts of boost control problems is quite a bad sign that something is wrong. And if it's very wrong, it could lead to the death of the motor as who knows what's been done to the car.

Really the turbo is too big for the engine but it doesn't sound like its set up properly. I have a GT3540 .63 a/r with a 50mm w/g on my RB30/25 and it makes 20 psi by 3000rev/min. I don't know if you'll get those kinds of numbers on your RB25 (what size exhaust housing have you got 0.63a/r, 0.82a/r or 1.06a/r. ?) but you should be getting better than what you are reporting. Put your location (nearest town,city) up in your profile so people can suggest a suitable workshop or if you're lucky someone living nearby might come and have a look for you.

what you describe sounds like the vacumn leak i had a few weeks ago, it would register boost to the boost guage but most of that was leaking till it got over 5psi and got fed some of it...then it would actually accelerate.

does it idle smoothly? is it a bit jerky?

hey guys thanks yeh im not an expert on cars and my location is wollongong new south whales im not sure on sizes etc im just reading the advert from the guy i purchased it off a few of my mates have recommended screamin performance does anyone know much about them and yeh it idles fine and im reading boost off the boost gauge i havent looked at the hand held ecu to see what the psi is on and yes i have the dyno report that came with the car sorry for the stupid questions etc but am trying to learn as much as i can and enjoy my car

thanks

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