Will this spring height be ok?

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Ant

Ant

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Hello there!
I'm in the process of putting my cylinder heads back together for my 318. I have bought Hughes 1110p valve springs to use with my new cam. The intalled height spec is 1.660'', I have 1.640'' with the shim, which is 0.020 shorter. If these were the old stock springs, I would not care as much, but I don't know if it would be fine for these way stiffer springs. My gut tells me it would be fine, but to play it safe, I'll check here.
 
As long as your cam lift is not "pushing" coil bind, i think your fine. Just a tad extra pressure off the seat. Good luck with the break in, done right you'll be fine.
 
Ant said:
Because the valves and seats have been cut, so a shim was used to make up for the height difference with the old soft springs.
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But your not using the old spring now.
Without the shim does your installed height, for the new springs, equal the recommended 1.660.
 
Jadaharabi said:
But your not using the old spring now.
Without the shim does your installed height, for the new springs, equal the recommended 1.660.
Click to expand...
It's at 1.700, 0.040 higher without the shim. If an extra .040 of height is ok, then I'll ditch the shims.
 
Chk specs for spring psi with valves closed. Then chk specs for spring "rate", and do the math. Make sure not too high for cam or it could wipe a lobe.
 
The new cam? What are the recommended spring specs? They need to be factored in when adding shims.
 
Jadaharabi said:
Get a .040 shim in place of the .060 and should be right on the money.
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It looks like my options are .015, .030 and .060. I can go with .030 and be higher by .010, or go with .030 and a .015 and be .005 under.
 
With the seats and the valves freshly ground or lapped, I would remeasure the height to see if anything changed from the previous setup. If not I would go with the .030 & .015.
 
I would not use any shim thinner than 0.030" that comes in contact with the spring. It could get chewed up.
Another option to fine tune spring height is plus & minus 050 valve keepers. In my experience, they usually deliver less than 050, more like 035.
 
Bewy said:
I would not use any shim thinner than 0.030" that comes in contact with the spring. It could get chewed up.
Another option to fine tune spring height is plus & minus 050 valve keepers. In my experience, they usually deliver less than 050, more like 035.
Click to expand...

They make hardened shims. If the shim is getting chewed up your valve train is telling you there is a problem.
 
Jadaharabi said:
With the seats and the valves freshly ground or lapped, I would remeasure the height to see if anything changed from the previous setup. If not I would go with the .030 & .015.
Click to expand...
Going with .030 and .015 should do the trick, it gets me in the ballpark. Thanks for the suggestions.
 
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