>
> A bit off the subject, but still the same thread.... Someone recently
> commented that the air-injected heads were _stronger_ because of the
> cast-in bosses. Sorry, not my experience, nor that of many others.
> The cast-in bosses are drilled, which sets up stress points that make
> the heads extremely prone to cracking. In my own experience I have
> handled three air-injected heads and all three were cracked, usually
> around the #2 cylinder spark plug hole. At least with my '73, doing
> away with the air injection had more to do with getting a solid head
> than with removing the power loss due to the pump. I have heard
> similar stories from several parts dealers as well.
> A. B. Bonds, whose head is not cracked
>
Hmmm... Interesting. Lindsay Porter, in his MGB Resto book, claims the
air injected heads are stronger, I believe based on the advice of the
machine shop he was using. (Its in the section about boring the engine out
to 2 liters if you want to check it out).
Jeremy DuBois
Programmer/System Administrator
Thermalogic Corporation
'74 MGB, '76 Spit
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