M30 Turbo Head Re-Build
After doing a bunch of enhancements and modifications, I had a major problem with the head. Both rockers on #4 had broken. The cars history shows that rockers had broken previously. I put this down to the fact that the original tuner set a 7000rpm limit. There is no need for this motor to be seeing 7krpm as it starts dropping power at 5500rpm and the stock valve rockers had probably seen 7000rpm far to often. Just when I got into tuning the Autronic, it was all stop for a major head re-build. This allowed for some further enhancements 'while I was in there'.
Here is the problem, broken f'king rockers:
Here is the problem, broken f'king rockers:
#4 broken intake and exhaust rocker. They have broken across the narrow section at the eccentric slot.
General tear down pics.
.12mm MIG wire O-rings in block, 7:1 forged fly-cut pistons (before cleaning!)
Head was re-worked with weld repairs to pulled threads and water jacket holes, re-skim, valve job, new seals, new rocker shafts, rockers and ARP studs made up to 90 lb.ft with a stock Elring gasket. Head work done by Hi-Tech Cylinder Heads, Malaga, WA, removal / reinstall by me
The old set up was a major hazard and once caught fire on the dyno as the oil in the fibreglass wrapping caught fire. The head had also pulled a few exhaust manifold suds and there was hot gases melting everything. The clutch reservoir melted down on a dyno run (as has subsequently been relocated). Not any more; the new heat management strategy is ROBUST.
Built metal shields for steering box, removed all the shitty oil drenched heat wrapping and replaced with aluminised sheet.
All back together with nice new heat shielding and thermal lagging, ready to fire-up.