I'm trying to set up my Trick flow 270 head for a solid roller cam. The springs that came on the head is 240@2.00 and 600@ 1.28. I have a Bullet solid roller cam that they recommend 260 to 280 closed and 600 to 700 open. My cam is .650 without the lash intake and .624 exhaust. I added a .060 shim and got the installed height to 1.94 with a closed reading of 300 and open of 600 at 1.285 on the intakes. The retainer is a -.050 already. Would I add more shim on the exhaust side to raise the open pressure but this would raise my close pressure? What's the best way to do this. These are 500 per inch pound springs. TFS-16318-16. Do I need a stronger spring? Also coil bind is 1.118. Thanks Matt

Try shimming all the springs so you get them from .080 to .060 from coil bind at max lift (verify the lifts at the retainers with light checking springs also)and see what pressures that gives you

I'd add another 0.060 or even 0.090 shim to get the pressure up a bit more and to reduce the distance to coil bind. If you add another 0.090 shim you should be good on both pressure and coil bind. You'll be slightly higher than what they recommend for seat pressure but that probably isn't an issue. You can call Bullet and confirm with them. When you give them real numbers sometimes the recommendation shifts a bit.

Ok! Thanks for all your help! Matt

It's easy to determine. A 500lb/in spring will gain 5lbs of pressure for every .010" you compress it. Starting at 240lb/in @2.00. Using the coil bind number of 1.200" plus .060" safety factor you get 1.260". Add .640" lift and you get 1.900". Subtract .020" for lash. Now you actual installed height is safe at 1.880". So if needed you could easily shim to that height. I would check actual coil bind of every spring first. But that would get you to 300lb/in on the seat and 630lb/in open at a actual lift of .620" at the valve..
Doug