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10psi Ok After Fmic?

nsta

By nsta,
in Engines & Forced Induction

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nfi Community Regular

nfi

Posted
Posted

10psi will be fine. Some people run 12psi with no problems at all. A friend of mines old series 2 used to run 14psi with no problems at all.

It is common though for the ceramic wheel to come off the turbo above 13psi. At 10psi you would have to be unlucky.

The safest thing to do is put the car on the dyno and wind the boost up. Might cost you $60-80 but will be well worth it to have the peace of mind.

James

TTT Grand Master

TTT

Posted
Posted
10psi will be fine. Some people run 12psi with no problems at all. A friend of mines old series 2 used to run 14psi with no problems at all.

It is common though for the ceramic wheel to come off the turbo above 13psi. At 10psi you would have to be unlucky.

The safest thing to do is put the car on the dyno and wind the boost up. Might cost you $60-80 but will be well worth it to have the peace of mind.

James

You User id is so well suited to your response

TTT Grand Master

TTT

Posted
Posted

I'll put in a little more effort as I have work to do and I don't want to do it so....

considering you have said that you had 7psi before with stock setup, that you have an R33 gtst.

with the new fmic, you have better cooling for your intake air.

so yes you can turn the boost up to 10 psi.

but consider the following.

1 - your turbo's ceramic exhaust wheel may break due to the increase in 2 things... exhaust heat and turbine revolutions.

2 - you will also probably (most likely) start to get a misfire at around 5000rpm with increase in boost as the r33's do this. a simple fix is to reduce the gap of your spark plugs down to about 0.8 - 0.7mm

3 - you have a stock fuel pump - this should be upgraded immediately as a safety measure.

4 - to get the most out of your new cooling and extra boost, you might want to get some sort of ecu (like power fc) or piggy back (like SAFC) so that a tuner can make adjustments to your tuning to make sure you have a higher power output and also safer at the same time.

don't think that 10 psi is a safe limit and that your turbo will not break here.

even when stock some have been known to break.

so you increase it, you increase the risk of kablaamoo for turbo.

Having said that, a stock R33 turbo second hand is about $350

or youo can buy one of MANY garrett turbo's from like $1500 +

good luck

benl1981 Grand Master

benl1981

Posted
Posted

Some stock ECUs don't mind 10psi but I think with a FMIC and exhaust your airflows will be a lot higher so you may force the ECU to run very rich and retard the timing (you will then lose power!!)

I am running 10psi but with a PowerFC, a SAFC may do the job - not as tuneable though.

I considered 10psi to be a safe level, but you never know. May last 2 weeks or 4 years. The turbos are getting older now and even R34 ones have gone pop around 12psi.

Depends how you use it. A track day will sort it out. I think I will drop boost presure to 7 or 8 psi if I hit the track.

Links Veteran

Links

Posted
Posted

Check what it's currently running with an aftermarket boost gauge.. mine runs 0.66Bar (8psi) stock.. after putting on a bleed valve - it spikes to ~0.7ish (9/10psi)..

anyways - yeah - check what it's really doing - than decide.. also depends on how you drive.. if you constantly drive around on boost of course your going to increase the risk of something happening..

benl1981 Grand Master

benl1981

Posted
Posted

At the end of the day you cant predict it really. A lot of WRXs boost there TD04s up to 17psi which also has a ceramic wheel, strange the nissan ones are so fragile.

I love the response of the factory turbo. If I replaced it I would like to drive a car with a HKS 2530 and one with a GCG high flow to compare the two.

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