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Hi, I was hoping someone could help with trying to maintain boost in between gear changes. It hits 16psi then drops right down to around 3psi. It takes a second or two and then gets back up there. Just not sure if this is normal for my setup which is as follows.

R33 GTS-t RB25DET

GT3540R .86

Turbosmart 48mm ext wastegate

Tomei poncams

Blitz SBC id3 boost controller

Apexi N1 exhaust/ hi flow cat

Fmic

all required supporting mods... makes 434 RWHP

Any suggestions would be greatly appreciated

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Either of the two will help obvious double clutching will keep the revs up during changes but the atmo bov kills boost as vents air instead of recirculating.

there wont be a difference in how boost is held between an atmo and recirculating bov, they both do the exact same thing bar the obvious part where on recirculates back into the intake

its normal for a turbo that size to take a second to respool inbetween gear changes. If you dont have a bov at all, that can cause the turbo to "lag" inbetween gears due to compressor surge, so get a nice sized bov thats going to breathe well and that should help.

Other than that, theres no real streetable solution, unless you like flat changing, antilag etc etc, its just the joys of having a large turbo on a smallish displacement engine

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Well you'd think that but how many people do you notice running insanely low psi gate opening or insane high gate psis? heaps..

So if it opens to early leaks, opens/doesnt open well/dose etc means boost is going to drop off because air is not correctly exiting the system.

Dont forget youve got that gate on there.. spring??

sorry i couldnt make out any of that lol

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Thanks for the reply.....yeah should have said. It has an atmo BOV with a soft and hard setting. I think it may be on too soft. I will adjust it and see what happens. It was on the car when i bought it...is the adjustment option just a rice thing?

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Thanks for the reply.....yeah should have said. It has an atmo BOV with a soft and hard setting. I think it may be on too soft. I will adjust it and see what happens. It was on the car when i bought it...is the adjustment option just a rice thing?

adjustment option will be for your bov spring to suit your vac/boost. if it's too tight it will comp surge, which is why they can be adjusted.

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