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i am getting the engine cutting out on me when i am driving....

It does seem that that 4 psi could be right. As it sort of spools up, but doesn't really throw you back in the seat at all....

Theres just a lot of sounds....... spool up noises, which probly exagerates the power its putting down.

i am using the 040 bosch fuel pump, which seems to be doing fine...

dyno might be the best option.

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well, it does go.

theres no leaky bov... as i am not running one...

I have no tacho on it, so its hard to estimate revs. But say boost hits at 2800 rpm. I get around 4 psi up to around 4700 rpm. the boost stays there. Then from 4700 rpm it boost to 7 or 8 psi. That would be revving it to say 5500 rpm or so.

But you can notice that the boost gauge needle sits on 4 psi for a long time. More than what i have seen in other peoples r33's.

I rechecked the boost line gauge, and that seems fine.

Only problem i am seeing is that the boost is staying at 4 psi for a fair bit. Theres no fuel pump issues, as the car has a bosch 040.

The timing may be a problem. But i am pretty postive that we have set the timing back....

What is the normal state for the timing to be set at, and how can i tell when setting it. I have the crank angle sensor where the screws are pretty close to being retarded timing.

i do have a simple boost bleed valve, that i could install, but would like to get it running righyt first.

What sort of boost should i be getting and at what rev range.

e.g psi@? revs...

cheers

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Stock RB25 skyline boost is 5psi to 5000rpm, then 7 psi to redline. Its 2 stage. If your boost guage is inaccurate (its not an autometer is it? they seem to go out of cal), that would account for the 4 psi instead of 5.

Usually when a cat back is fitted the drop in back pressure gives another couple of pounds boost, but then you get 7psi to 5000rpm and 9 psi to redline.

This is standard without a good EBC or bleeder.

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ah, well thanks. I dont like it. 5 psi to 5000 rpm sucks. i dont really like revving the car out to redline. But at least in know nothing is buggered,

I have the stock dump pipe, but everything else 3 inch. Also have front mount intercooler.

I do have a liquid filled autometre boost gauge, and i'd say it goes to around 4 psi then to 8 psi.

So 5 and 9 psi you seem to be correct.

If i was wanting to get the boost to come on earlier would using the bleed valve do this. Where do i set it up from. Never really used one before. DO i t piece the valve just after the actuator hose, and tehn run that up to a plenum nossel....

And having the bleed valve tightened, or loosened has what effect. Upping or lowering the boost.

11 or 12 psi would be what i would run on the standard turbo.

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4 seems a bit low if you have 3" back except the dump, but 9 seems about right.

I have never connected up a bleed valve, only an EBC, so sorry I cant help there. Pretty sure that tightening the valve will restrict air, thereby increasing boost, which is what you want as it is boost pressure that opens the wastegate.

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