miami993c297

iTrader: (6)

I am about to install the LS1512ML valve spring on my engine.
The advertise coil bind is 1.070"
Seat Pressure is 130lbs @ 1.800"
Open Pressure is 395lbs @ 1.150"

The camshaft max valve lift is .622".
Target is 0.050 coil bind at max lift.
Consequently install height is 1.742"

My question is what are going to be Seat and Open Pressure with the new install height?

Christian

KCS

iTrader: (20)

You can find the rate and calculate from there. I'm 99% sure PAC lists the spring rates on their website. It's normally expressed as lbs/in, so if it's a 350lbs/in spring rate, it should gain 35lbs for every .100", 3.5lbs for every .010", etc.

miami993c297

iTrader: (6)

Thank you KCS,
Listed is... Rate Lbs/In : 408


Christian

Da Z06

At 1.742" install height you effectively gained: 23.664lbs or 408 + 23.6 = 431lb open pressure.

miami993c297

iTrader: (6)

Is there any issue running those PSI LS1512ml at 0.050 of coil bind???


0.050 Coil Bind good or bad with those PSI???

Christian

KCS

iTrader: (20)

That's a good question to ask PSI, but I would be okay with it as long as you verify the valve lift. I measured the lobe lift and valve lift with the stock rockers on my last engine and got more valve lift than what a 1.7 should have given me. It was more like 1.72:1.

miami993c297

iTrader: (6)

I just got off the phone with Dave at PSI, and he says that is a great set-up as long as I will be accurate with the install height...which I will triple check.


Christian

KCS

iTrader: (20)

Sounds like a good plan.

miami993c297

iTrader: (6)

Following-up after some intensive testing.
Those PSI LS 1512LM are handling the Yella Terra 1.7 rockers without any issues revving to 7400rpm.