[Healeys] Alloy Head

[Larry Varley]

Hi Mike, first of all I'm not saying there is anything wrong with your 
setup, only that 4 cylinder heads once cracked are known to crack again. 
Not always, but you do have to weigh up the costs relative to a new 
head. I get my head gaskets made locally in 1MM ( 0.040 thickness ), at 
$180.00 Australian Dollars.
I think it pretty easy to throw around claims of better performance, and 
talk about air flow improvements but that isn't all there is to the 
equation. What about the designs ability to provide thorough fuel 
atomisation through the ports and into the chamber, not rocket science? 
No more like a black art! Just increasing port sizes does not mean more 
power other than maybe at full throttle.
Basically where are the before and after horsepower and torque figures 
to back up claimed more power?
The alloy heads being offered may well be better, but it can only be 
proven on a dyno across the whole rev range with horsepower and torque 
figures and most importantly with before and after results on the same 
bottom end, then there are no doubts. Are the figures out there for any 
of these alloy heads? It would be interesting to see them.
As a matter of interest some years ago when the late David Woodhouse set 
about improving the original DMD 6 alloy cylinder head, the biggest 
improvement was made by increasing the height of the inlet ports. 
thereby improving the transition between horizontal and vertical air flow.
Cheers
Larry Varley