Hi All,
I have a 1989, Firebird, 305, TBI, Vin Code E, Auto Trans, Calif. Emissions.
I just put in a new stock crate motor from Jasper. I have superchip, hi flow TBI, Shift Kit, MSD Ignit.
I have 1.6 ratio Gold Crane Roller Rockers. What I need is a beffer cam that will pass Calif Smog. Any Suggestions will be greatly apprecitaed. I think I am limited due to my 1,6 rockers, but I dont know.

Brad

 

With those rockers, your lift will be increased. It's easy to run into valve spring problems.

Is your motor a roller cam motor? It was, stock; is that what you have now? Also, what heads are on it? Casting # would be best.

 

My motor is roller cam, I just have stock heads I have no idea what the casting number is, the car is not with me now, will be picking it up after xmas, my job relocated me so I cant give you the casting # now, sorry, what would the casting number tell you??

Also have had no valve spring problems yet, I have about 20K on the gold roller rockers.

 

the problem is if you increase the cam, your going to have valve spring problems. using 1.5 ratio rockers would solve most of the problems. the stock heads won't handle much lift, but will handle a bit more duration.

 

But going from the 1.6 back to 1.5 with a bigger cam with just reduce the amount of lift defeating the purpose of a bigger cam, other than more duration with a better cam.

 

A bigger cam also increases duration. Increasing the lift with stock heads will yield about increase in power.

 

Going with more duration over lift will normally give "better" results. I say "better" because you can 'over-cam' an engine.

Using a cam with the same lift and more duration is one of the benefits of a roller cam. The valves snap open faster, therefore giving the cylinder more time to fill under max lift.