I'm currently running the Comp Cams 272 cams on stock valvetrain. With my 3065 turbo I'd like to rev it a lil higher but safely on my stock bottom end. I was looking into the Brian Crower valve spring & retainer kit. Anyone have any feedback on them? And with them how high could I rev staying within a safety margin? What's the highest/safest I can rev as it is now (stock valvetrain)?

 

Uu can ugrade your valvetrain that would allow u to rev to whatever u want.. BUT the stock rod bolts will say goodbye.. i wouldnt rev over 8k on the stock rod bolts.

 

I have the bc spring and retainers. I havent had any problems. I think that you can rev it up to 8000 with a good tune.

 

The balance shafts will become a liability if you try to rev to 9K. That little belt often breaks at high rpm taking the timing belt out with it and bye bye engine. Upgrading springs and retainers is only 1 of 2 steps in reving to high RPMs. Removing the balance shafts is step 2. Not a fun job, btw. I just did it.

 

I'm running them also. No issues. I only rev to 7800 cause I'm a pu$$ though, not because it can't take it.

 

What about those kevlar belts i keep hearing about? And I'd be happy with a 8k rev limit. Right now i keep it under 7,200rpms w/stock valvetrain & my 272s though i hear of a few reving higher. Keeping in mind my Comp Cams are 114, 112 LCA i believe while HKSs are 110, 110 LCA i'd like to know if i can safely rev a lil higher or just play it safe until upgraded valvetrain....

 

I have heard of these kevlar belts actually wearing down the teeth on the cam gears. Either way if the balance shaft belt breaks it can do a lot of damage regardless if the belt if kevlar or not.