those springs aren't good for much over 5k....at a minimum swap your mustang springs on, however I'd suggest the tfs spring kit, it's cheap and worth the money.
Hmmm....while i will admit that i've never tested the spring pressure of those heads, i don't see why Ford would bother using a different spring since the cam isn't much milder than a Mustang cam. So....i don't retract my statement but hey, your avitar is "GTP" so maybe you know more than me...lol
i've done a lot of research on this, as well, the cam is different, it's a torquey truck cam...both the cam and the springs in the explorer are matched together, and they don't rev like an HO cam will, you'll stand a fair chance of valve float if you run the ho cam or better with those springs.
Buy new springs. There is no use using old used worn out springs from a Mountaineer, to replace used worn out springs in the Mustang. One guy I knew, replaced his 85 Corvette valve springs, and what a difference it made if just the stock replacement ones. His were so worn out, they were floating all over the high RPMS.
i've done a lot of research on this, as well, the cam is different, it's a torquey truck cam...both the cam and the springs in the explorer are matched together, and they don't rev like an HO cam will, you'll stand a fair chance of valve float if you run the ho cam or better with those springs.
That does make sense....thanks for the correction. I wouldn't have said they were the best choice, but i figured with a stock cam, you're not going to be pushing 6250RPM and getting good results anyways.
those springs aren't good for much over 5k....at a minimum swap your mustang springs on, however I'd suggest the tfs spring kit, it's cheap and worth the money.
When you say TFS kit I was wondering which one you had. I see they have a kit for 110 lbs. and 0.542 total lift or a kit for 125 lbs. and 0.600 total lift.