| the same block was rebuilt each time - bored minimum over each time with new matching set of OEM pistons. I'm at maximum bore now so will be scouting around for a new block, or might get OEM short block... The first time the head gasket blew engine was stock with stock ecu, the leak pressurized the cooling system and blew all the coolant out of the overflow - the engine was cooked before I knew anything was wrong. Replaced the heads with a used set off the board. The local shop (which is pretty good and consciencious) lightly decked and checked everything including completely going through heads and put together the long block. With this build I upgraded ECU to JWT, 555 nismo injectors, and SP 500's. This engine detonated with the JWT boost jets and as noted lost a cylinder before I could figure out why. I suspected but never proved that the wastegate actuator on the passenger side was interering with a bolt head on the oil filter adapter and may have been causing a boost spike. The second rebuild was done at the same shop with another bore job, new pistons, same heads but this time I installed a boost controller and was very careful breaking it in and setting up the boost levels. 91 octane is as good as it gets up here so I was running 14 psi on high boost (which is where I was when I melted down this time.)
The timing was on the low side of factory spec at 14 as I wanted to be safe. lol I actually haven't checked it for several months but I only put a few thousand miles on the Z every year since it is my fun car. It lives (ed) a pretty pampered life - though I have autocrossed 3-4 times this past summer, which basically means running it a redline in 1st and 2nd gear for 90 seconds each run. With the koyo temperature has been rock steady.
I've had a suspicion in the back of my mind for some time about the ECU - but the chip is a genuine JWT and I figured I could trust it. Everything I've read on the board indicates their chip is pretty conservative and tends to run rich. I have listened carefully for detonation and have not noticed any with this set-up. So now that it is too late to do much good I'll ask the obvious question - is there a way to check out my chip and see if the programming is correct?
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