80Stang
Well-known member
Been long since I started a new post, and really don't know if there is a lot to say even now.
A lot of talks here about higher rpms, and like many (me too) have noticed the stock valve springs effectively prevent high screams. Maybe they are a fuse of some kind, to save the engine. Naah, just made to make 8-cylinders look more powerful.
Anyways, I have followed the great handbook by David & Dennis and I got a set of 60's 289/302 valve springs in my hands, and finally measured the spring pressure for closed valve at stock assembled height. D&D have the spring mentioned in the book with rated V8 figures. So here are the measured results:
80lbs @ 1.590" (typical 200/250 installed height)
Coil bind: 1.053"
The physical measurements are so close to L6 stock spring that it is a direct replacement. This spring will also live with any "normal" performance cam for what comes to lift but of course care has to be taken if the cam is very long.
Now, this is what most have in there: let me present the stock spring, a used survivor:
45lbs @ 1.590"
Coil bind: 1.024"
Factory spec is 51-57 @ 1.590", at least according to '80 Shop manual.
I'm running Comp Cams springs, rated at 48 @ 1.600, thus stock specs. And I thought everything from CC is performance. These valves stand good up to 5300rpm with a FSPP / CI 274H single pattern cam, where the power still was climbing at the dyno but valves started floating.
OK, the spring is the Sealed Power VS-733 and is available for about $3 each at Summit and other places near you.
Until the next year :roll:
A lot of talks here about higher rpms, and like many (me too) have noticed the stock valve springs effectively prevent high screams. Maybe they are a fuse of some kind, to save the engine. Naah, just made to make 8-cylinders look more powerful.
Anyways, I have followed the great handbook by David & Dennis and I got a set of 60's 289/302 valve springs in my hands, and finally measured the spring pressure for closed valve at stock assembled height. D&D have the spring mentioned in the book with rated V8 figures. So here are the measured results:
80lbs @ 1.590" (typical 200/250 installed height)
Coil bind: 1.053"
The physical measurements are so close to L6 stock spring that it is a direct replacement. This spring will also live with any "normal" performance cam for what comes to lift but of course care has to be taken if the cam is very long.
Now, this is what most have in there: let me present the stock spring, a used survivor:
45lbs @ 1.590"
Coil bind: 1.024"
Factory spec is 51-57 @ 1.590", at least according to '80 Shop manual.
I'm running Comp Cams springs, rated at 48 @ 1.600, thus stock specs. And I thought everything from CC is performance. These valves stand good up to 5300rpm with a FSPP / CI 274H single pattern cam, where the power still was climbing at the dyno but valves started floating.
OK, the spring is the Sealed Power VS-733 and is available for about $3 each at Summit and other places near you.
Until the next year :roll:
