I finally got my problems ironed out with my new aluminum
non-crossflow head, and things are working great. The first time I
put it on, two manifold studs started to pull out of the ally. Took
it off and had Helicoils put on. Reinstalled it, and NO COMPRESSION
IN ANY CYLINDER. Not knowing what was up, I removed it again and
took it back to the manufacturer. Pulling out the valves, it
appeared that little pieces of aluminum swarf were stuck to every
valve seat! Although the head looked clean after the Helicoils were
installed, enough crap had fallen into the runners to get sucked
into the valves on initial startup. Cleanliness counts! Third head
gasket was the charm. Noticed that copper/composite Payen gasket has
some tacky sealer stuff on it, but sprayed it with high-temp sealer
anyway.
Installation was explained as torquing the head down, setting valves,
running 'til hot, retorquing, and letting it cool completely before
resetting valves. It ran great. The new head has a late-head
pattern combustion chamber and the smaller intake valves and slightly
bulleted bronze guides, an interesting contrast to my early iron head
with big intakes. Can't directly compare performance, since I had a
sticky exhaust valve which prompted the whole project. Does seem to
breathe well, and the smaller intake valves probably contribute to
higher velocity in the RPM range I run. I'd love to find a rolling
road dyno locally and see what the engine does.
Chris Attias
'64 MGB
'84 Alfa Romeo GTV-6
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