Z32 sounds bad when on boost!

[RobH]

Hi guys,

I'm resetting up my maps having put some Nismo 555s in (was previously on Venom 550s). I've done a few other bits and pieces whilst I had the plenum off - mainly fixing a few small boost leaks. I've done a basic K constant adjustment after starting with a fresh image file and resizing injectors. I've not checked the AFR whilst driving yet but I suspect it's running extremely lean when on boost. The exhaust note is suddenly much louder and more 'ragged' as soon as the boost kicks in, almost sounds like it's about to backfire, power is also not very impressive at this point. Maybe the boost is too much for a 1.1mm spark plug gap now I've sealed up the intake leaks??

It's running really nicely at idle, despite having a leak in the clutch booster (I blanked this off whilst setting the K constant). O2 sensors are currently disconnected.

I suppose the best idea would be to log the AFR whilst driving but it's not practical at the moment so I was hoping someone on here might be able to give me a headstart with some advice.

As a point of note it was a little bit like this (but much worse) when I had a massive boost leak at one of the intercooler hoses. It all suggests too lean to me...I don't think it's a leak this time as pulling one of the larger vacuum lines off the balance bar at idle causes a stall.

Any advice appreciated.

Cheers

H

[Matt]

when you can check the AFRs... not much you can do until you have done this with a zero'd fuel map to check your k constant and latency