rice burner

I brought the cc306 cam a few days ago and I know I must replace the lifters too but what about the valve springs? I've read that if those aren't upgraded to the right size it could damage my motor! I'd prefer not to touch the heads until the motor is broken in. Also how much would it cost to have a mild port job on the heads?

69z-28

julian the CC306 will work fine with stock heads. you wont need to replace the lifters assuming the factory roller lifters are in good shape, they will be able to handle the 306. the valve springs however MUST be upgraded. i would recommend either the 918 springs or the easy bolt on kit from Crane, its a set including shims, springs, retainers and keepers for like 180 bucks, the part number is 10308-1. valve job would help but definitely not necessary if your valves are in good shape. i would recommend replacing the valve seals tho for the hell of it. they are cheap and easy to do when your in there.

rice burner

I'm pretty much over my budget now with this engine. When I pulled the old motor i tossed the rockers and lifters so I would have to buy them new which would be about 350 and u saying that kit is about $180 so I will look into getting that monday. Thanks!

Phate

Heads are not a must with pretty much any cam. Heads just make the cam a TON more beneficial, making the air flow better.

But as said earlier, the springs must be changed.

mpe331lx

Again: the springs MUST be changed!
To take advantage of the CC306 you must shift at a 6800-7000 RPM. If you dont plan on taking it that high, sell the cam and get a CC503.

69z-28

the 306 will work well on a stock motor, its about the limit tho. you will use a lot of it even shifting at like 6400. the cam will start to drop off a bit after that from what i've seen. people seem to think the cam likes to rev higher than it actually does. for example, my 224/224 starting dropping off in HP around 5600. that was a solid running middle range cammed LT1, so im sure the 306 would benefit from better flowing heads but you dont need to take it much higher then 6400.

rice burner

that does seem a bit high of a rpm but once I have the heads ported then a dyno will determine the max rpm right?

mpe331lx

The car wont make peak power that high, but will get the best track times when shifted that high. It is not all about peak power, some cars have to be brought past peak power at the shifts to perform the best, a CC306 lt1 is one of them.

Sinister95Z

The CC306 will 'work' with the stock heads, but it will definetly not be living up to the potential that cam has to offer. Alot of people including Comp Cams give advice to only go as high as a 503 with stock unported heads.

If you are planning to upgrade the heads later on down the road, just stick in the 306 and be happy that you are ready for future mods.

As stated before, without a doubt you must change the springs. It is a ticking time bomb with stock valvetrain. The cam has way too much lift and would break piece after piece. If you are going as far as putting in a 306 cam, why skimp on the supporting parts? I wouldn't even think about putting in that cam without springs, retainers, locks, valve seals, studs, guideplates, pushrods and new rockers. All the specs on that cam are given with a 1.6 rocker ratio in mind.