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Im installing A Lunati .602 lift w/1.6 rocker I purchased the spring kit that Lunati recommends and valve springs w/ 1.750 at 108 lb. of seat pressure dont seem to be enough. Did the math and open pressure turns out at 386 lbs. which is reasonable for hydraulic roller lifters.Im more concerned about seat pressure,and possibly coil bind if I shim,
I think 130 lbs should be where id like to be. Any body got any ideas out there............??

Seems a little light to me on the closed pressure, I would agree that 130-150 seems closer to what it should be. What does the manufacturer reccomend for the open/closed pressure?

JimM...what are you runnning on your hydra roller? What are your cam specs just for comparison?

Open Pressure 1.250 @339 lbs
Closed Pressure 1.750 @108 lbs.
Coil bind 1.060
462 lb. Rated spring

Did the math and came up with
462 lb X .602 (lift w/1.6 rocker) = 278 + 108 = 386 lbs. Open pressure

Lunati recommends these springs on the came card but at A 1.5 rocker ratio, Under .475 lift id be ok with this spring but Im shooting for .602 lift and dont want to lose peak power

There is no way I would run any performance hyd roller at 108 seat
I would want a minimum of 130 & prefer 140-150 in a small block depending on the lobes
350-375 open should be ok depending on valve weight
Unless you go to a Beehive

Lunati seems to have a real problem with some of their spring spec & it is documented many times with people having valvetrain control issues.
They have actually changed some of them

How much room do you have (installed height)?
The Isky 8005 is a good choice or the Comp 977 is a decent spring, this is what Brodix uses as an upgrade for hyd rollers on the RR & IK heads
The Isky 6105SP would be excellent but a little spendy with the retainers & locators
Another is the Patriot Gold with matching parts & it is a lighter spring package but also not exactly cheap,,

A lot depends on what you can get for installed height

My Installed height is 1.730 on the intake and 1.750 on the exhaust and also have .050 + locks to raise it up if needed

The Isky 6105SP or the Patriot Gold would both work well
In Lunati the 74721LUN at about 1.750 is what I would use
There are also a couple of Beehives that will work very well

You need something that coil binds at 1.120 or less with .600 lift & 1.780 installed

What are the specs on the cam? If its .475 lift with 1.5 your lift with 1.6 will be .506 not .602.

.565 lift @ 1.5 = .602 @ 1.6

Thanks alot Mike appreciate the help I would definitely like to look into the behive spring ...