In a message dated 1/18/03 2:27:00 PM Pacific Standard Time,
owner-mgs-digest@autox.team.net writes:
> Do the aluminium cross-flow heads for MGBs live-up to any of their
> claims? Are they an upgrade, or an expensive placebo?
>
No, they really do work. Surprisingly, they don't work all that much better
than a full race radically modified cast iron head in terms of outright power
output, but if you think about the fact that only one valve is open at a time
(more or less) and that the flow of one of the (modified) siamesed ports on
the CI head is about the same (or maybe even a bit better - remember that the
4 port head has to have ports that fit between the pushrod tubes) as the
crossflow head, it makes sense.
OTOH, for low and mid range, the X-flow works beautifully, and better than
the full blown CI race head at those rpm ranges.
> Also, does a 2L engine really do much more than using the +060" pistons
> for 1868cc's?
>
Yes, but I am not a fan of anything bigger than about 1950 cc without
sleeving - there is just to damned much core shift in the stock blocks to
have any comfort whatsoever about wall thickness with anything bigger.
BTW, the crossflow still isn't as good as the REAL THING - I run twin 45 DCOE
on my racing Twincam motor, and it has better BMEP than either the HRG or the
fully modded CI head.
Bill
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