high compression pistons are relief cut in v-8 engines, and
maybe also in your jag which has dual cams. both of these
engines have thier valves at an angle to the piston travel. in
the spit, the valves travel parallel to the piston travel, so no
relief is needed in the piston. i aslo believe that if you are
getting valve float at high rpm's, you need to consider getting
you valve springs checked. spitfire springs should be good up
to the 8000rpm level without float or modifications. as far as
the exhaust valves, the profiles should be almost identicel as
the intake except for the phase in relation to the crank (ie:
shifted 180°). i hope this makes sense, because i've even read
through my competition manual many times as well as my workshop
manual and none of them say anything about worrying about valve
interferance.
--- "Arthur H. Smith" <arthurhsmith@compuserve.com> wrote:
>
> Message text written by nikolai jaremka
> >it seems to me that this would give you some bad results.<
>
> My reason for doing that with the play dough is to take into
> account valve
> float at high rpms. if the valve opening won't cause a
> problem ie fully
> open at piston half way down what about the exhaust??? and
> why are high
> comp pistons relief cut for valves.
>
>
> The arthur >;-} :4 O:-)-}8<
> www.anedieco.com/tr.htm
> kit car aka 69 GT6
> 82 XJ6 Jaguar (Jennifer)
> boxy thing on wheels aka ford aerostar (boxy lady??? 8-} )
>
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