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1776 Head Replacement

Based on advice gleaned both here and elsewhere, I've decided to replace both heads on the 1776 which some previous owner installed in my speedster. One of the original heads had an intake valve seat hammer loose from its bore and lodge behind the valve. Fortunately, there was no damage to the piston, just a little nick, and nothing hard broke off, so no scoring in the cylinder. Talk about luck!

The original heads are Brazilian VW 043 castings with 40mm intake valves, 35.5mm exhausts, and dual valve springs. I measured 59cc combustion chamber volume. They were ported and polished. I liked the engine's performance, so I wanted something similar. 

I settled on a set of CB's Panchito 044s with dual valve springs. They have a slightly larger 61cc combustion chamber, but my original heads had .040" gaskets in addition to an 0.065 deck height, for a calculated static compression ratio of 6.828. I guess they did this so it would run on regular (87 R/M octane) pump gas. The added 2cc of chamber volume with the Panchitos, coupled with deleting the head gaskets actually increases the static CR to 7.197. This should be still be acceptable with regular pump gas, but if it knocks I can always step up to 89. So I'm leaving the Panchitos as-is, no flycutting required. 

I measured my camshaft's duration, lift, and lobe centers, since the oil pump was glued in solid. From the numbers, it's an Engle W-110, which works with 1.25:1 rockers, so I'm upgrading to CB's super stock complete kit and elephant feet for better contact with the valve stem. A little extra lift should help the engine breathe better, that's what I'm thinking. 

Other parts on my list are a set of the matched Panchito intake manifolds, a set of CB's aluminum super duty pushrods, the straight ones, not tapered, and racing pushrod tubes, which are required for clearance with the 1.25:1 rockers. Lastly, I'm getting a set of NGK DP8EA-9 12mm, 3/4" reach spark plugs. 

I'm about to pull the trigger on this order. Can anyone think of something I forgot, or find flaws with my thinking? I'm always open to constructive criticism. 

Eric

57 CMC widebody, 1776, Dell 40s, IRS, 4 wheel discs, 18" Boyds, 225/35/18

Last edited by Eric (McGruff)
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