> If I was planning to put a supercharger on an engine, I would want
> to make sure that the comression ratio is correct. I believe (may
> be wrong) that you have to use low compression pistons so that
> you w't blow the headgasket. The compression with the
> supercharger will be way above stock anyway.
>
> Maynard HIrsch
No, that is not the reason for using low compression pistons. Your stock,
either 8.7:1 or 8.0:1 (I think) pistons, will be fine for moderate (no more
than 9psi) boost. Fuel and timing variables will need to be manipulated to
avoid the preignition and / or detonation you may encounter, which is often
remedied by fitting lower compression pistons.
However, in the 9.0:1+ engine compression range you may be asking for a bit
of trouble in an older LBC motor if you introduce forced induction to it.
In that case, a rather more simple method of lowering the compression ratio
is offered, a thicker head gasket. Mordy Dunst, TR List member and racer,
makes his own copper head gaskets in various thicknesses for this purpose.
http://www.headgasket.com
Anyone interested in supercharging, in the theory or actual applications,
should go purchase Corky Bell's book, Supercharged!. Unlike Corky's turbo
book, this is much more comprehensive and quite a bit better written.
Practically every aspect of supercharging is covered. In my "library", it
has superceded all my other forced induction books as the reference I use
the most.
--
Kai M. Radicke -- kai@radiohead.net
Former owner of a supercharged TR6
http://www.pil.net/~felix/supercharger/
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