One of the 'bits' I have sitting in my basement is a pair of TFS Twisted Wedge
heads. Unfortunately at this point they are not near the top of the to-do list,
but they will get there. I can measure the height against the stock 289/302
heads and report back if anyone is interested. I don't think there's a real
problem unless you insist on running the cast aluminum valve covers (which
includes me).
I think that with modern head gasket technology the thermal expansion
differential between aluminum and cast iron is going to matter one iota so long
as the engine is assembled properly.
I ran a Toyota hemi (iron block, aluminum head, solid lifters) at silly power
levels for years, with only one head gasket failure. The failure was directly
attributable to the advance plate in the distributor coming loose and having the
timing go to about 60 degrees BTDC.
The valve lash could be set hot or cold; the cold spec was .001" tighter than
hot, and this worked beautifully. Set it cold, warm up the engine, and measure
it: you get the hot setting.
The only difference that I can see is that Ford heads are pretty darn small
(meaning flexy) around the outside.
BTW, I used Fel-Pro Print-O-Seal head gaskets until I went to a 0.160" overbore
(can't do that with a Ford, can you?) and had to use the TRD ones. Fel-pro now
also makes wire-lock head gaskets, and you can get the TFS heads with reliefs
for wirebead head gaskets.
Theo Smit
tsmit@home.com
tsmit@novatel.ca
B382002705
PS Jim B (or anyone else), if you send a picture (.JPG) of your car to my @home
address, I'll post it on my website. Include pertinent details.
> -----Original Message-----
> From: Bob Palmer [SMTP:rpalmer@ames.ucsd.edu]
> Sent: Monday, August 02, 1999 9:33 PM
> To: Michael M. Kelly; Sunbeam Tiger mailing list
> Subject: Re: Aluminum heads
>
> Michael,
>
[] <snip> ...
> they sit a bit higher than the stock cast iron 289 or 351W heads, which is
> an issue in for the cramped Tiger engine bay. But, at least the TFS heads
> can be milled up to 0.180" to increase compression and decrease height.
[] <snip>
> The thermal expansion differential between cast iron and aluminum is
> somewhat problematic. For example, if you use solid lifters, setting the
> valve lash is harder to do. With cast iron heads you can even set them
[] <snip>
> Robert L. Palmer
> UCSD, Dept. of AMES
> 619-822-1037 (o)
> 760-599-9927 (h)
> rpalmer@ucsd.edu
> rpalmer@cts.com
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