Hello,

I would need some help that i have a set of skunk2 pro1 cams.
I'm not sure i can run it with the 70Lbs Supertech valvesprings??
I don,t want to rev it above 9k rpm.

Setup:
B16 fully forged 9.0:1 CR, Garett gt3076R 0.82A/R, skunk2 pro intake, Ferrea comp+ valves, Supertech valvesprings and titanium retainers.
Thanks for the help!

 

Someone else may have more to say, but if possible I would try to sell the 70lb springs and instead at least use the Supertech 85lb.

"I don't want to rev it above 9k" makes me think you're going to redline at 9K or at least around there, that in consideration with the turbo size, I'd want a bit more weight in the springs.

 

I would think as long as you don't get coil bind or close to using your setup and not reving to the moon that may introduce valve float, you should be totally fine with the 70lb springs. They're nearly 20lbs over stock, so wear and tear will be a bit more but shouldn't have a problem. I also just think of it as the higher the seat pressure for a near stock Rev limit, the more resistance it has to rotate the engine robbing power and creating more wear.

 

I tend to Co-sign with Maxcapacity here. As long as you're being realistic with the RPM, turbocharger size, and goals of the car.. Shouldn't be an issue.

 

Are we upgrading springs for more rpm or to combat cylinder pressure?

Stock springs can handle the rpm….. Coil bind would be a spring length issue…. Spring length is directly correlated to install height.

 

I would say your upgrading springs for rpm only, If it didn't matter for rpm based, you could free up hp by having less engine rotational resistance using the weakest springs that generate just enough force to close the valves if rotating the engine by hand or slow speed.. Actual engine speed and those valves will bounce and float..
Really all you need is a spring that will have the least amount of seat pressure (to lessen the wear on valve seats, cam lobes and rocker pads) but provide full control of the valve, keeping it in contact with the rocker while being pushed open and while following the cam lobe profile during closing.
Combating cylinder pressure is dealt with the valves being closed. Any force generated will be passed through the valve-rocker, then cam lobe.. So the springs wouldn't have any effect as for cylinder pressure, they just need to hold the valve up in contact with the rocker at all times and stay seated when closed.
Coil bind is simple, if the cam lobe height vs spring compressed height doesn't allow clearance, your pooched.
OP just needs to make sure the springs are compatible with the cams and the spring rate selected is fine to run for his rpm goal.
Those are my theories.. lol

 

Thanks to all of you guys!
Actually I decided to sell these cams. My friend has a tuner 1 intake cam (but no exhaust) so I planning to put that cam in and remain my gsr on the exhaust!
I think its far enough for my expectations!

Thanks again!