[Demon Dave]

Quick question really: will I have any problems with over-boosting if I stick a Mines VX exhaust on an otherwise (completely ) standard R34 GTR?

thanks in advance.

Dave

 

[Toby Broom]

I thought that was pritty much expected by changing exhaust?

 

[Bajie]

Is yours a full system or are you leaving the downpipes alone.
I would think if it is from the cat back you would be ok. Prepared to be wrong though.

I changed my HKS full system to a Kakimoto Full Dual and was getting serious overboost at high revs.
However, after approx 3 weeks, this overboosting has stopped. I can't for the life of me explain why though.

 

[leggus]

Is yours a full system or are you leaving the downpipes alone.
I would think if it is from the cat back you would be ok. Prepared to be wrong though.

I changed my HKS full system to a Kakimoto Full Dual and was getting serious overboost at high revs.
However, after approx 3 weeks, this overboosting has stopped. I can't for the life of me explain why though.

Who knows Bajie, does the ECU detect different input and try to remap itself slightly for different readings?

This is the case (so i'm told with WRX) may be totally wrong with Skyline..

According to Central Subaru, when exhaust changes are made (i.e. decat) then the standard WRX ECU takes about 4 days to re-work out whats going on..

If you dont use your car on a daily basis, this may be the case, taken 3 weeks to try and sort itself out, may be barking up the wrong tree but worth a thought.

 

[Pulse D]

Who knows Bajie, does the ECU detect different input and try to remap itself slightly for different readings?

I know this is the case with an EP3 / DC5 Honda Type-R ECU. It took two or 3 short journey's for the ECU to 'learn' it could breath better (fitted Mugen induction & SPOON exhaust system), and then compensated some of the fuelling to match.

 

[R33_GTS-t]

After I went to a Trust 90mm downpipe and decat, the boost reached 0.9bar above 5600rpm (stock 0.75bar - R32). Excellent I say!

A cat-back shouldn't make as much difference... I think.

 

[Demon Dave]

The exhaust will just be a cat-back for the time being, so leaving the cat and the original downpipes in place it should (I'm hoping) be enough to stop the boost going too high.....

at least until I can get a boost controller sorted out.