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This question is not getting answered in another thread and I'm not able to find definitive answers.

I just recently bought a 33GTR and noted that on full boost it's sitting on 7 on the stock gauge, which as far as I know is around 13.4-13.6psi. I thought stock GTR's were supposed to run 9psi? Which would be about 3/4's on the gauge?

Here's a pic showing the boost solenoid, note that the stock restrictor is still in place inside that hose with the yellow mark on it. The only other thing I could find of note was the earthing cable shown which leads up into the back of the spark plug cover so presumably doing something for the coils. I note that the silver box beneath the boost solenoid has JECS written on it, is this stock? It's connected to the solenoid and into the fuse box.

Ideas would be greatly appreciated as I'm not comfortable with that level of boost on Ceramic turbo's especially in this hot weather.

Cheers

post-23873-1167982950.jpgpost-23873-1167982978.jpgpost-23873-1167983023.jpg

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OK the plot thickens, I just thought to myself, I'll reset the ECU and see if that helps, in doing so thought I'd check it to make sure it was stock... guess what... It Reads Impul HI_POWER CONTROL UNIT then SGTR-1133

Wonder if that is controlling my boost?

post-23873-1167983466.jpg

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It sounds all stock to me, as it is from the factory and will be fine. I beleive 7 is stock. However, bumped to get answers from the Guru's who know for cert.

Edit:

0.7 of 1 Bar with restrictor in.

1 bar with restrictor removed (appx 15psi).

Edited by Sinista32
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The restrictor is definitely in the line, I've checked it myself.

700mmHg = ~13.5psi that's up around what people claim is the max safe limit for the car, with this in mind and the fact it has that Impul thing in it, I doubt it's stock. Can anyone tell me anything about the computer? Also, could it be controlling the boost? Surely there'd be a module or something somewhere?

I think I'll put the car on a dyno and get some more info on what it's doing too but next weekend, this weekend/week is all about servicing and fluids etc.

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I'd suggest an IMPUL ecu is not stock, and yes a remap can control boost levels but so can a lot of other things. If it is at the boost pressure you say then rule of thumb suggests that it shoud be OK but your concern re ceramic wheels is valid.

My stock 32 GTR maxes at about 9 psi, 33 is probably similar.

JECS and DENSO make just about every electronic part on the car.

Dyno is a good idea, see what it's actually doing.

Edited by Scooby
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I've gotta find out where the closest 4wd dyno is and go from there. It's definitely reading 7 on the stock gauge, I wanted a pillar mounted gauge anyway so I'll get onto that as well. I'm waiting on some info back regarding my options with the Impul stuff.

It might be valid to note that the car has an after market core, not sure what it is until I get under and have a look but hopefully it's keeping the turbo's cooler.

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