i have a set of ported lt1 heads flow GM Aluminum LT1, three angle performance valve job bowl ported, valves back cut and new valve guides
Combustion Chamber: 54cc Intake Runner: 175 cc Intake Valves: SBI Steel1.94” Exhaust Valves: SBI Steel 1.50”. flow 255 cfm at 500 lift(only flow number i have). i was thinking cc304 or cc305 cam with 1.6rr. car has 150k on the odm. car allready has full bolt on's rebuilt 4l60e and a rebuilt rear with 3:73's. the cars starts up every time with no smoke, no knocking and no missfires or anything of that sort. only leak is the rear main seal. is this a good idea to do H/C swap on???? i don't want to go through all this work and spin a bearing or crack a ring. i am also replacing the oil pump. i have no idea if the motor was ever swap out or anything so as far as i know is the original motor. post your thoughts good or bad idea????

 

I'm no expert but can share my experience. I went with a bigger cam the 847 which is a tad bigger than the 306, did 1.6rrs, all the valvetrain goodies, and stock heads. The odo had 89k miles, knew it was risky but decided to do it anyway. The engine was original. It lasted 2 hours , spun a rear bearing, just too much cam on the old engine. I've seen others successfully get away with it, but have seen others like myself crash n burn too. The rear main seal is you have is a one piece, easy to change yourself to fix the leak. Felpro makes a good seal, one is an upgrade to the standard, has a better seal, few bucks more. I won't tell ya to do it or not, kinda up to you and how gutsy you feel about it but you have almost twice the miles mine had it would be questionable IMO. Good luck either way.

 

Friday is the one year to the day from when i cammed my car. It had 105K at the time now it has 118K so i am doing ok so far knock on wood.

 

what hp numbers are you putting out??? the cam i am gonna put it isn't that crazy, but i hope it's ok to do

 

If I were you I would just spray it till it blows. Then do a forged rebuild with the H/C, and you'll already have the spray and be good to go. You'll prolly save money in the end because the motor is gonna go sooner or later; it would suck to do all that work and then have all that downtime again.