Hello all--
due to Pandora's Box effect, my '72 B's engine rebuild is of course behind
schedule. I'm "tinkering" with its previously freshened (approx 5 thou mi
ago) head, to the tune of basic porting and cleaning up of chambers. Its air
rail holes were plugged by the DPO and I noticed in each exhaust port
underneath the valve there protrudes a single tube, apparently made of
brass, about 5/32" in diameter and maybe 1/4" long. I assume that's what
actually injected the air charge into the port. Anyhow, I cut each off with
a grinder, back to the contour of the port. I'm porting it using the
manifold gasket matching method (bolt gasket in place, scribe opening,
remove material, repeat on manifolds) and find that the ports will be opened
quite a bit (exhaust approx 5/32" primarily on one side, intake about 1/8"
all around circumference). Hopefully this will be worth the time (almost 1
hour per port!)-- now I see why some tuners charge $1200 per head, plus they
know what they're doing! It'll be married up with HS4's eventually,
replacing the Weber DGV that replaced its HIF4's, and a stainless Peco
header/system. Oh, and bored 40 thou over, warmed APT street cam, and
balanced. Comments?
Larry Ruggiero '72 B roadster
Warner Robins GA (at Atlanta Brit Car Day the 18th, but on my Triumph
motorcycle instead)
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