In a message dated 7/4/03 11:38:23 PM Pacific Daylight Time,
tr6taylor@webtv.net writes:
> Alan---There's probably more than one reason for going to the second,
> shorter and lighter valve spring found in the later engines.
> The first one that comes to mind would be the backup it provides in case
> an outer spring should break. I don't think only a single lighter spring
> would let the engine rev much beyond 3,000 but it would get you home.
> The broken spring would also rattle as engine speeds increase, just to
> let you know.
>
> There might also be a benefit of the extra tension such a spring would
> provide on the valve train, as each cam lobe "turned the corner". I can
> see where adding an inner spring could reduce the rate of the outer
> spring, if desired.
>
> Dick
It has been a while (OK, a long while) since my days as a Camaro SBC hot
rodder when cam and valvetrain issues were fresh in my mind. If memory serves
me
correctly the dual springs did offer a degree of security in case of breakage,
however the primary consideration was to eliminate or minimize the likelihood
of valvetrain resonance's that could lead to valve float. Kind of like the
effect you might experience if you drove your car down a bumpy road with no
shock
absorbers.
Jeff Dewey, Secretary
Richmond Triumph Register
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