Dee Jackson wrote:
> Hi Gang,
> I have the head from my Spit in the shop now for a rework. The guy is
> making it flat (tho' it was out <.0025), grinding the valves, and generally
> freshening up the whole thing. He believes the springs to be weak, based
> on some numbers that he had in a valve spring book. I've looked in several
> references (Haynes, Bentley, and various parts books) and can't find any
> numbers on what the pressure of the springs should be. I *can* find free
> length, load length, # of turns, rotation, etc. but nothing to tell me what
> the spring should read in lbs. at an open and closed valve position. Anyone
> have info on those kinds of numbers? I'm only concerned because his
> reference did not specifically list Spitfire 1500 (US spec.) but had Spitfire
> "lumped" (no pun intended) in with several other models. I am going to have
> him put new springs in but I'd like to be able to tell him what the springs
> should be rated.
> FWIW, it took me about 2 hours total time to have the head in my hands and I
> did not have to use the "rope trick". In fact, it came off with only a
> little persuasion. Maybe that's why the gasket seeped oil. At any rate,
> you gotta love the ease of access in working on these cars. Wish y'all
> could've heard the machinist snicker when I walked into his shop with that
> "little, tiny head" under my arm.
> Please copy me direct as I'm on the digest version and, as always, thanks.
> Dee "looking forward to springs" Jackson
> '78 Spit FM90204UO
> email@example.com Gilbarco Inc. Greensboro, NC voice 910/547/5007
Don't know an answer to the question about valve spring rates, but if
you are going to replace the springs anyway, I would go with dual valve
springs. Not much more expensive than single (~$10.00), but you get
better high RPM capability, ie: less likely to experience valve float.
IMHO, the extra money is well spent.
77 Spitfire 1500 - undergoing cajones transplant - FM66513UO
62? Vitesse/Sports 6 convertible - HB5635LCV
92 Ford Tempo GLS V6 (Ultimate Q-ship!) - 1FAPP38U1NK150073