Right now I have a CC304 cam.. and I am running stock rockers and push rods. I would like to make my cam a little "bigger" by going with a higher ratio rocker arm. I have LT-4 valve springs. I think the last time I asked I was told I would get spring binding if I ran a 1.6 rocker. I really hate to change the springs out.. does anyone know if I could get away with a 1.55 ratio rocker?

 

The actual lift difference would only be about 2%... not worth it IMO. You won't notice the difference, and likely, neither would the dyno (Assuming you already have a 1.5 roller rocker, not the stock stamped stuff).

Probably not a good idea to get that close to the spring bind height anyway... should always leave some room for error.

 

I thought stock rockers were 1.5 I do have stock stamped rockers.. and plan to upgrade to RR.. I was hoping to gain a little more lift too.. but I've been told 1.6 it too big for my springs..

 

Change your springs and get 1.6 RR's. I've never seen a 1.55 rocker, Comp makes a 1.52.

 

Comp will special order 1.55's in the Pro-Magnums. I run a set on my exhaust side.

 

Sweet.. I'll do that.. if someone can assure me my springs won't bottom out..

 

what valve springs are you running? The CC304 with 1.6 rockers only has .533/.544" lift. The 1.6s also increase the time (aka duration) that the valves are open making it act like a slightly longer duration cam. The cost to special order a set of 1.55s (which would only give .517/.527" lift) seems like a waste to me. That is unless you are running a little more advanced combo like Fred

 

I have LT-4 valve springs..

 

Again, change the springs and get the 1.6 rockers. It'll give you a nice little boost in HP. The LT4 springs are really not that good for any cammed LT1.

 

I really dread changing the springs with the heads on the car. Would I pick up my HP by going to a 1.6RR? Enough to justify the head ache?

 

Yes, you will pick up some HP by upgrading to the 1.6 RR's. You may even pick up HP from the spring change, by better controlling your valvetrain.

 

I agree with you. The 1.6 and better springs is the smart way to go. I currently have the cc305 cam, with cc beehive springs. If I change to 1.6 RR ,how will that effect midrange power??

Thanks

 

yea LT-4 springs will only go to .525 :-(

 

Just do it right: begin with checking the cam card for your cam and see what spring pressures and heights are recommended for the cam with 1.6RRs. Should be at least a dual spring. Suggest going with non-self adjusting RRs with the guide plates and hardened pushrods----check your geometry to ensure the correct PR length. SB std length, but better to make sure.

If you bring each cyl to TDC you should be able to change out your springs without dropping the valve into the cylinder. Be sure to get the proper spring compresser for the job. For that matter, be sure to check out all recommendations on this board regarding the RRs, Springs, PRs, Guide Plates, etc.

With the additional lift and a bit more duration, along with the proper combination of parts you should get the maximum power out of your cam along with a solid, well-controlled valve train. JMHO

 

LT4 springs? You'll gain power by getting a decent spring in there...