math class needed on valve springs

[FireSale]

Your spring info matches the PAC 1220 beehive spring. Is it this type of spring? It sounds like you want to change the rate and pressures of a spring you have to a spring you want and I don't think it works that way. You can change the seat and open pressures by changing the installed height but the spring rate is dialed into the spring in the manufacturing process. This spring installed at 1.780 with a .457 lift would give pressures of 192 and 362. You can tweak out the IS until you have a seat pressure of 170, but the open pressure will move in the same relationship that 192 is to 362. That's the spring rate doing that.

[gmonde]

Originally Posted by FireSale

Your spring info matches the PAC 1220 beehive spring. Is it this type of spring? It sounds like you want to change the rate and pressures of a spring you have to a spring you want and I don't think it works that way. You can change the seat and open pressures by changing the installed height but the spring rate is dialed into the spring in the manufacturing process. This spring installed at 1.780 with a .457 lift would give pressures of 192 and 362. You can tweak out the IS until you have a seat pressure of 170, but the open pressure will move in the same relationship that 192 is to 362. That's the spring rate doing that.

yes,,actually the current spring I run now is Lunati 74820-16 - Lunati Pacaloy Valve Springs that matches the PAC springs,,just getting my numbers so I can check them ,they have been in the car for a couple of seasons

I checked the pressure before I installed them and they where around 170-180 @ 1.780 installed spring height,




the PAC 1220x spring is the next option but it will have to much spring pressure
Installed Height (in):
1.900 in.
Seat Pressure at Installed Height (lbs):
160 lbs.
Open Height (in):
1.250 in.
Open Pressure (lbs):
400 lbs.

thanks for the reply's ,much appreciated !