I have a Comp xr275hr cam 54-426-11 - XFI? RPM High Lift

Its in a Lq9 with stock heads (317) running PAC single beehive springs needing help determine what is the best roller rocker 1.7 or 1.8 ratio for my setup?

 

witch Pac springs ? you have to watch for coil bind you will be very close to .600 lift
and alinement over the valve tip. also valve cover clearance.
the only one's i found to fit the best were Summits own brand
if you want 1.8 roller's. they are really well made with big trunnions.

 

I would run the stock rockers...

 

Depends on the ramp rate of the cam. 1.8s don't like a high ramp rate.

I run yella terra non adj. 1.7s. They are working out real well for me.

Only rockers I know of that need valve cover spacers are Harland sharps.

 

Why I'm wanting to buy roller rockers is I have no factory rockers and OEM rockers with trunnions would cost the same amount

 

PAC 1218s

 

I wouldn't run the 1.8s unless you're upgrade the springs.

0.566/1.7 = 0.333
0.333x1.8 = 0.599

0.568/1.7 = 0.334
0.334x1.8 = 0.601

 

Looks like im going to try summit racing 1.7 rockers not seeing near the bad reviews vs. Other brands and there priced good.

 

I'm really curious why you wouldn't run the stock rockers?

 

I'm running yealla terra 1.8 and have had no issues in 30K + however I got mine slightly used for $150. I think $400 was the cheapest I could find them new.