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Hi Ya'll,

I have a stock plumb back on my s2 r33... It has a trust front mount, 11 psi of boost, high-flow turbo...

When I change in-between gears it seems to hesitate and kangaroo a little bit... Wondering if this is because the BOV isn't opening fully and the pressurised air isn't getting out properly??? The BOV does make a bit of a fluttering noise...

Cheers

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  Quote
does spound like it is not opening fulling forcing the boosted air thru the turbo causing a flutter.

Yeah it kinda does... The car bucks when I change gear, so it I was worried that something is causing the airflow to be interupted

I had a similar issue although not exactly... I went to a Nissan/Jap wreckers, got me a BOV from a soon to be wrecked R33 gtst(you can pick em up in the For Sale section as well), bolted her on and presto problem solved. Maybe you can service your current BOV.

IANAM (I am not a mechanic) :(

  Quote
what ecu do you have?

What AFM do you have?

If you have a stock one of either, I can guarantee the problem lies there

You my friend have hit the donkey on the head. I have stock AFM and ECU.... Is it the extra pressurised air in the system (due to larger turbo and front mount) causing the ECU to behave like a pork chop? If so, hows that? I'm not hitting R&R or fuel cut....

  nuclear_skyline said:
You my friend have hit the donkey on the head. I have stock AFM and ECU.... Is it the extra pressurised air in the system (due to larger turbo and front mount) causing the ECU to behave like a pork chop? If so, hows that? I'm not hitting R&R or fuel cut....

There you go

I had a stock AFM and powerfc and I was getting the exact same problem between gear changes etc too.

But just remember the the R&R hits at about 10+psi on the standard turbo, which means it would be 9psi \ 8psi on a Highflow because it is moving more air volume.

You really need to get some form of aftermarket management - so go and pick up yourself a Powerfc and a Z32 AFM, and 90% of your problems will go away.

  Quote
how much power u making from that setup?

At the moment I am making somewhere around 190rwkw... Although I think the dyno I ran it on was reading high.... So not sure, somewhere around that though I think....

  Quote
But just remember the the R&R hits at about 10+psi on the standard turbo, which means it would be 9psi \ 8psi on a Highflow because it is moving more air volume.

I hit for some reason R&R about 12psi... Well at least I hit MORE R&R at that stage.... The car seems ok atm...

I am planning on putting a GReddy EMU in within the next couple of months.... Hopefully that will let me finish off the engine mods for the time being and go about my way with the suspension...

Will get ECU!!!! I PROMISE!!!! Dont quite get how that is causing the air to bounce around though... Surely it is a mechanical issue rather then a tuning issue... THOUGH - I know there are issues caused by having mods and no ECU and that I'm sure I have some of them, dont understand how it would be casuing this issue

will drop it this afternoon... Heres a question then: If I drop it back, and it is presently R&Ring, will I immediately notice that it isnt R&Ring? Or does it take time for the ECU to learn?

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