Pac 1518

[itsfess]

I was wondering if any one had experience with these springs. I just picked them up and was trying to find out what a realistic lift would be.(they claim .650 max)

[side2000]

it depends on what rpm you plan on doing with them, but generally their max is conservative so they dont have a bunch of people complaining about mangled valvetrains and grenading motors. realistically, you wont get a cam even close to .650 lift (w/ stock cubes) so dont sweat it. seem overkill though but if you got 'em use 'em.

[itsfess]

Actually I had purchased the 1218 springs but they we're out of stock and i got a pretty good deal on the upgrade.

[vettenuts]

The amount of lift they are good for will be based on how you install them. Once you measure installed height you should be able to compute distance to coil bind and from that value, with the required clearance, determine lift capability. The advertised lift really doesn't mean much.

[itsfess]

I guess i should have said this. the 1218s are rated at .600 max lift and the 1518s are rated at .650 lift. Their the same spring just with a coating/ surface treatment. does this sound reasonable?

[SOMbitch]

The amount of lift they are good for will be based on how you install them. Once you measure installed height you should be able to compute distance to coil bind and from that value, with the required clearance, determine lift capability. The advertised lift really doesn't mean much.

^^^^^^^ Vettenuts nailed it!!! Again!!!!lol

I like to shim until I am .060 from coil bind. This gives the best seat pressue for better valve control and better valvetrain harmonics. I have read it even gives longer spring life......

[BowTied]

^^^^^^^ Vettenuts nailed it!!! Again!!!!lol

I like to shim until I am .060 from coil bind. This gives the best seat pressue for better valve control and better valvetrain harmonics. I have read it even gives longer spring life......

It seems somewhat counter-intuitive but that would be true (in and to itself). I don't know a whole lot about engine internals, but springs for the most part, will last longer and perform more linearly if they are used closer to the full compressed side. (Given the same distance of travel.)