But surely the lift on a 1500 is the same as the 1300 engine, so why fit
doubles on the 1500?
Tim
Carter Shore wrote:
> Dual (or triple) valve springs can allow for greater
> valve lift, and/or more pressure, and/or less stress
> to the spring.
>
> Coil springs will 'bind' if compressed too far, this
> is a function of the wire diameter and length of the
> wire (shorter wire gives more space between coils for
> a given uncompressed height).
>
> Smaller wire diameter to accomodate more lift means
> less pressure, so we use multiple springs. Two seems
> like a practical limit, tho' some get away with
> triple.
>
> Shorter wire for more lift and greater pressure means
> more stress in the spring wire, leading to shorter
> life. Some drag race springs are only good for a few
> runs before they lose pressure and must be replaced.
>
> Carter
> Great stuff seeking new owners in Yahoo! Auctions!
> http://auctions.yahoo.com
--
Tim Dafforn
University of Cambridge
Structural Medicine Unit
Cambridge Institute for Medical Research
Hills Rd, Cambridge CB2 2XY.
UK
Tel. (01223) 763230
Fax. (01223) 336827
http://smokeroom.cimr.cam.ac.uk/
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