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Hey guys, just got a problem hoping someone can help me with it or point me in the right direction to get it fixed.

I have a rb20 with a turbo from hypergear, nistune ecu, injectors, front mount, full exhaust all the usual mods, when i rev it out from 1st gear to second gear in high rpm it bogs down/lag and then the power kicks back in once ur in second gear, its almost feels like u slam on the brakes inbetween the gear change. Uts getting really annoying and i dont know what it could be, i thought it could be the BOV, coz i had it blocked off so i thought it might have been the air going back out the turbo slowing the wheel down but unblocked it and it still does it, i also have the pipe that comes off the BOV just pointing into the engine bay, not back into the intake, its still a stock BOV aswell.

If anyone could help me out that would be much appreciated.

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i also have the pipe that comes off the BOV just pointing into the engine bay, not back into the intake,

Do you mean where the plumb back pipe connects into the intake pipe, it's not connected?

So you are sucking air into the turbo through the hole in the side of the intake pipe?

Air that is unfiltered and also not measured by the AFM?

This would be a problem me thinks...

The Bov plumb back pipe, it's not attached to the Bov right?

Is the other end still attached to the intake pipe between the AFM and the Turbo?

Have you blocked any of the open pipes?

Its just the normal stock BOV and the pipe that from the trumpet bit of it just goes to no where to the engine bay, it used to go to some pipe which took it back to the intake for the emision reasons, but since upgrading to another turbo i had to get rid of all that so that bit of pipe just vents to the engine bay, and no other pipes have been blocked either

Blame the tuner :P

Waiting on NIStunes reply. They emailed today. Hopefuly have a few answers tomorrow

send it through if you need a quick reply, have the tuning lappy at home tonight.

I also had this problem on the R33, happens the air doses backwards onto the AFM. It was fixed by relocating the afm into the cooler piping.

Definatey seems like the same issue, and to clear things up its not a lag issue, its a hesitation

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