MikeH

found these teeny teeth when I changed my gearbox oil: haven't been able to locate any pics of z32 gears so not sure what they belong to but have a constant barely audible scraping noise in 2nd and 4th, any ideas?

it could be the exhaust touching something it wasn't before but I'd also check the engine mounts, if they're no good your gearbox could now be sitting at a funky angle.

click me!

unfortunately it's not just the rail layout, cylinders 5 and 6 get the most air due to the plenum design and coolant flow in the block is most restricted back there.. I don't know which is the biggest contributor but you should still be able to manage a reliable 500 hp in any case.

well.. it doesn't cause detonation, it may stop it temporarily by putting you into safety mode but that only works if it picks up detonation under 3000 rpm, it's ignored otherwise. try checking your your timing and fuel pressure.

start with some chromies and work from there.. that slightly grey blue is probably my favourite factory colour.

sorry should have added, the drive is to get up to operating temp as you'll be in safety til then anyway.. you might want to also put your foot down a couple of times to test if detonation may be causing it.

if your O2's are no good, switching them out will only help with light-medium throttle and within a certain rev range. To check if you're in safety mode go for a drive then before switching off, put a test light or multimeter on your boost solenoid connector and rev the engine to around 2k. If you get power, you aren't in safety mode.

I may well have had a blocked turbo coolant line but the boiling did return.. Actually I thought I found the problem a few times but I think I finally know the reason for it. I didn't have an ECU bracket until a few weeks ago, I also hadn't boiled for a while until today when I went out after messing with the ECU and didn't bolt it back up. It was just a short trip on a cool day with no boosting and yet when I switched off, I heard boiling at the back of the engine. This just 2 days after I made a long trip on a very hot day using A/C and occasionally boosting but without boiling. I don't know the exact cause but you might want to check your ECU case is properly earthed.. Hopefully we can determine that this isn't just freaky coincidence.

it turned out to be a blockage in the coolant line running to the left hand turbo.. my symptoms were the left hand side of the plenum running cooler than the right, the coolant was boiling in the heater intake (you could feel the coolant boiling at the hose). The blockage had also caused the hose from the turbo to the heater intake at the back of the engine to blow, not much fun to replace. I disconnected the heater intake and the coolant line to the turbo from the front left of the engine, hooked up a foot pump and a small plastic bag popped out. :) dunno what the hell that was doing there but I can imagine that with the angles of some of these hard pipes, they could block through corrosion etc pretty easy too.