Have a a btr cam, trick flow 215x heads and fast 102. Looking to put roller rockers in the car for guide life and valve life. Looking at running yella terra rockers.What would you recomend for valve spring pressures? 7200rpm shift would like stability close to 8k incase of a miss shift.

Thank you

 

The PAC .660 springs will work well with that camshaft.

 

I wouldn't run any less than a Pac 1207x. I would shim them up for a touch more seat pressure. What lifter are you running? The thing about BTR cams is they are totally designed around a stock rocker and the lobes are aggressive. They are touchy to dial in if you deviate from their recipe..

 

Jhonson Drop ins with new trays.

 

What ever you go with, I usually recommend around 180lbs seat pressure for roller rockers.

With that being said, what springs are in your heads now, we may have a drop in that requires no hardware change.

 

not to change the subject but with a stock cam like the 02+ LS6 and a 1.8 or 1.85 rocker what kind of seat pressure would you recommend? in the past with that cam and rockers i ran PAC 1211x beehives but i feel i lost valve train stability somewhere between 6800-7000rpm.

 

I would drop ion some PAC-1276X's (150lbs seat)

 

I thought they where comps but I am questioning if they are the trick flows that come with the heads. Everything in there is pritty beat so i would like to replace it all.

 

TFS heads assembled come with TFS springs. If you are changing everything, I would go with the 1207X and a -0.050" lock for a 1.750" installed height.

PAC-1207X-16
PAC-R435-16
PAC-S129-16
PAC-L8116-16

 

Whats your thoughts about running a btr .685 and shimming it 0.020? That would be right at 178 seat and like 430 open?

 

I mean, I am going to recommend a PAC regardless

 

FYI, TurboBuick6 works for PAC, and knows as much or more about valvetrain setups than anyone here. I’d listen to what he has to say…