Things took a more interesting turn this past week. I spent the last few days tearing down the engine to prep for a mild-rebuild and cleaning. I actually did the bulk of the tear-down in a single night, only took me about 2-1/2 hours. These motors are stupid easy to work on (or to tear apart, anyway). Some of the upgrade parts in so far are Comp Cams rocker trunion upgrade kit, ported LS6 oil pump, LS7 lifters, LS2 lifter trays, and an LS2 timing chain.
Still need upgraded springs, chromoly pushrods, and a timing chain dampener to go along with the cam swap. Strangely enough the engine in its stock form didn't come with one, even though it has provisions for it (2 tapped holes in the block above the crank gear). A case where GM accountants (sadly) took charge of component selection. The addition of the dampener will help alleviate chain-whip problems that occur when going from WOT to closed throttle and hopefully help prevent the chain from breaking.
The block stripped except for the pistons and crank:
Stock oil pump. The one I'll be replacing it with from Texas Speed is a ported LS6 - should give me more flow and ~+10 psi over stock.
Stock cam. No gouges, looks clean. If I can't sell it I'll be making a sweet lamp out of it.
LS7 lifters vs. Stock Lifter. Note how the roller is completely enclosed in the LS7 design, which is proven for 7000+ RPM. It's unlikely that I'll be spinning the engine that high, but it was relatively cheap insurance to upgrade them.
Stock LS1 timing chain (left) vs. LS2 chain (right). Slightly beefier - the most cost effective upgrade before going to a dual-roller setup. Along with the addition of a dampener this should be pretty robust.
Bottom end
Everything looks clean. I plan on doing ARP mains and rods, and will be checking the bearings for any excessive scratches/gouging while I'm in there.
Cylinder Head Prep - Cleaning/Porting/Valve Lapping
Instead of spending $1500 on a set of Stage 1 LS6 ported heads, I've decided that I'm going to DIY port the 241 castings I've got myself. I've read that they can be made to flow better than the stock 243 castings used on the Z06 'vette, though they're really easy to fuck up if you aren't careful. I bought a porting kit and some carbide burrs from Eastwood for use with my die grinder, hopefully that will be arriving this week. More research to come on methodology, but with some patience I believe I can get good results. While I'm at it, I'll also be lapping the valve seats to help improve sealing.
Some supplies. WD-40 for keeping the rust away as the parts sit and IPA for cleaning parts. Also some engine assembly lube, valve grinding compound, and some valve lapping tools (basically suction cups on the end of wooden sticks).
Cleaned up the sealing surface of the head with steel wool and IPA to lubricate. I'll be lapping this (and all of the other critical surfaces) flat with a 320 grit aluminum oxide honing stone and using a layout fluid to help make high/low spots more visible. I read that going much finer than that diminishes the ability to achieve a proper seal - the gaskets need a little bit of texture to bite into.
So I'll be waiting on some supplies, in the mean time I'm finishing up the second valve cover - will post pics of that once it's done. Later.
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