Hi, I have a 2004 5.3 Vortec with a Z06 Cam upgrade and Z06 Valve spring upgrade. I also have long tube headders and a STS Squire Rear mount Turbo pushing 9 lbs of boost. I was going to upgrade my rockers to roller rockers but wasn't sure if I should stay with the 1.7's or go to the 1.8's Any thoughts???