StealthFormula

iTrader: (35)

I was told that if I want the most out of my cam (cc503 and stock heads) in terms of performance Im going to need to set my shift points at around 6400 or 6500. I've noticed some guys are spinning their stock headed 847's and 306's to 6700+ but Im just wondering if Im running a big risk shifting at 6400rpm? Keep in mind the car only has 12,000 miles and I have the Valvetrain to support it but Im not trying to spin a bearing or something along those lines yet I want the best track times I can get.

nighthawk15

The stock bottom end should not be spun over 6200 RPM from what I understand. Higher than that and you run a high risk of spinning a main bearing or causing some other issue.

NJLT1SS

I had a stock bottom end, TEA stage 3 ported heads, and XE 230 cam. It ran fine for 3K miles. Then went and had it dyno tuned, and we spun it on the dyno to 6500. The cam made power to 6300. It lasted one pull, and then tossed a rod bearing. I did manage to drive it home 80 miles on a spun rod bearing, including 1 hour of stop and go traffic on the NJ Turnpike. I personally think anything above 6000 and you are asking for trouble. Also, I think those powdered metal rods aren’t up to the challenge of added cylinder pressure.


Nick

Schweet97Z

iTrader: (35)

i have my car shifting at 6400. the cam made peak power at 6800 and that is where we stopped when tunning. dont be scared and spin it to 6400. i would take it higher, but then its really a ticking time bomb