Pelican Parts Forums - What valve springs to use?

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Yes, my engine is the one referred to above (euro 3.2 with John's 993SS cam, race valve springs and Ti retainers among other things), the machine shop who did the work on my heads screwed up. The valve guides had to have 1.5mm taken off them after the initial rebuild as some of the seals were damaged. It was using a litre of oil every 200 miles more or less after a top-end rebuild plus new rings. Not happy at the time, but it all seems fine now and I got the engine pulled apart and checked after 1500 miles for free, so in the long run, not a bad result.

[QUOTE]Originally posted by 911pcars
[B]For the record, anyone care to contribute some valve spring specs

I have a little information from a project I did, what specs would you be looking for?

Quote:

For the record, anyone care to contribute some valve spring specs

I have a little information from a project I did, what specs would you be looking for?

Since I couldn't find them in the factory spec book:

Free length
Installed height (as I remember, the spec shows height including the retainer; would like w/o retainer as other manufacturers describe)
Coil diameter, OD
Wire diameter
Installed pressure (John helped with this one)

Thanks,
Sherwood

Quote:

Originally posted by 911pcars
[B]

Since I couldn't find them in the factory spec book:

Free length
Installed height (as I remember, the spec shows height including the retainer; would like w/o retainer as other manufacturers describe)
Coil diameter, OD
Wire diameter
Installed pressure (John helped with this one)

Thanks,
Sherwood

Free Length on a stock 67-94 (years) spring is
1.625 on outer 1.5 on inner
installed height varies as to application 33.5 to 34mm (1.318 to 1.338 without retainers
spring seat thickness for outer spring is .194 and the inner .110 with the retainer offset .110 and the retainer is typically .070 to .080 thick if it is not Tiatainium so you would add .264 to the spring for the retainer and spring seat package.
wire dia. for outer is .150 and inner .120
Pressure or force valve closed is 32 for outer and 25 for inner combined for #57 lbs. @ 1.338 in.

Note the outer spring is pretty close to a progressive rate or non linear spring beacause of its windings and the inner is a typical constant rate.

sorry if this is fragmented
Best regards

Thanks for digging up this info. Much appreciated.

Sherwood

My pleasure,

These are very interesting cars and information is hard to come by.

Best regards