Not much to report lately. I have paused the engine assembly while I get the top end ready for installation. As it stands, the short block is ready to go.
As anyone who's used the ARP head studs know, one of the studs on the exhaust side needs clearancing for the cam sensor disc. In my case, I need .060" taken off. From what I've heard from other builders, this varies quite a lot.
I rechecked the piston to deck clearance, and found .003" above the deck. Much better than I initially thought. The machinist's deck height measurement must have been off slightly. Final Comp ratio now 14.55:1
Next major task is setting up the cylinder heads. New intake valves, so I had to carefully measure the stem height with a fixture and dial indicator. The valves and seat height were remarkably consistent, yet I still had to shim each intake valvespring to get the exact height.
What a boring way to spend the afternoon.... measuring a few dozen shims.
These were sorted to the nearest .0001". Probably within the measurement error. Regardless, I elected to shim the intakes a little closer to coil bind height. Last time, the intakes were .075" to coil bind. I intend to rev this engine a bit harder, so I have chosen to set the springs up at .060" to coil bind. This gives just a tick more spring force throughout the lift curve.
Now the exhaust valves need to be thoroughly cleaned... lots of carbon from the first build. Then I can set up the exhaust spring heights. It's a dirty job to de-carbon the valves, no wonder I've been putting it off till now.
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