Putting together a 582, had some PAC double springs on it. I hear many are switching to the triple springs. Any recommendations on what brand is holding up well?

I prefer PSI as does my engine builders but I’m not aware of any issue with PAC and you definitely don’t need a triple spring. Neither the 1000 HP engine in my Firebird or the 1300HP engine in my dragster have triple valve springs.

Doubles should be fine, especially if that has .870 lift or less. My conventional headed 632 that is north of 1150 only has doubles. I will say, 150 passes and i put new ones on.

Lift is .871 - .824

quote:

Originally posted by SmokinChicken:
Lift is .871 - .824

What is net,and is the profile agressive or a normal out of the book lobe, that is the number that counts.

Somewhat on the aggressive side.

I'd look real serious at the camshaft card recommendation.

The PAC 1224 good to .850 net lift
PAC 1228 good to .900 net lift

Both are 1.625 OD dual springs without a flat damper

I’ve used PAC’s and PSI’s and both are good, no breakage.

Many are in love with way over 300lbs seat pressure.

The above springs are around 280 and work fine for me.

7500 and under

If you spin it to higher rpm with steel valves you might want the triple springs with 300+ on the seat.

Lobe lift x rocker ratio minus lash is your net lift. And there is generally some loss to deflection.