Okay, back to Blazers... or more specifically Diesels
finally got the motor pulled down. the tl;dr is I'm going to run it...
the not-so-clean under the turbo still worries me
Overall, it's not terrible, there's still cross hatching on the cylinder but it wasn't running right
bottom end looks good
number 8... yeah
somehow water got inside in August/September in San Diego....despite the seller's assurance that it was stored indoors.... the risk one takes when they buy on ebay. I probably would have been better off just rebuilding what I have - HOWEVER, let's not forget I do not have a qualified machine shop, so the hell this is may pale in comparison to that pandora's box.
an explanation. Usually the critics are point on right with GM's stuff. GM beta tests on its buyers - which is utter crap, but is what it is. The point is that over the years, the product becomes quite good for what it is. The heads
are a perfect case-in-point. My dad went to rebuild a 6.2 but gave up when, after 3 sets of heads, there were no heads without cracks. Strangely GM even suggests that there are 'run them' cracks and no-go cracks.... but, in the 20 years since the first 6.2, GM started developing better heads culminating in these aftermarket heads that fix everything wrong with the older heads. And they cost less then it costs to simply rebuild a set of heads... for new castings.
and that's a foretaste of what you'll see here.
Fluidampr makes a SFI certified balancer for these motors... they're the foundation of building a motor that can handle 30 psi of boost. Stock, 10 psi and you start lifting heads and blowing head gaskets.... that is if you don't break the crank because the balance ring spun on the balancer.... not cheap, but a lot cheaper then replacing a motor due to broken crank...
to this I add ARP studs. The 'right' way would be replace the pistons with lower compression pistons.... however, even with all the updates, these motors start coming apart after 725 lb torque. Then you need billet cranks (they have them).... in this case, I want 350 hp and 525 lb torque. For what I'm building - that should be sufficient.
what you won't see, though, is a cooling system update - because the 99 motor has it already. GM started with (by memory) 30 gpm cooling pump. The motor would hot spot at idle. They then came up with the 67 gpm pump for the turbo motors... with about the same result. Then came the mamma jamma, in 1997, they split the water system (to allow simultaneous cooling on both sides - effective dividing the cooling into 2 banks of 4) and put a 137 gpm pump on the motor. That pump solved the cooling problems - to the point that the uparmoured H1s didn't immediately melt down in the sands of the Middle east.
also, to be seen later will the the turbo upgrade.