I'm soon to install an Lt4 cam (no, not the HOT one )
Should I change my rockers? (75,1xx miles)
If so roller tips? Full-Roller rockers? 1.5 or 1.6?

 

If you have the extra cash sitting around it is certainly the time to do it...but my cam swap cost me about $500 bucks and that is buying a used LT1. There is alot of stuff that need to be replaced while your in the engine. It really starts to add up! But, I wish now that I had waited until I had the extra loot to shoot for full roller rockers.

BTW...go for full roller rockers and it depends on how high the lift on the cam is whether to go with 1.5 or 1.6. 1.6 will give you slightly more lift but our heads can only handle so much...

 

the cam lift is .475/.480 lsa 115

 

oh yeah I'll be swapping the heads too.
I'm not sure yet
btw highest potential after porting:
1)sr torquer's???
2)aluminum l98's??
3) vortec's????
4) unported and shaved arf 180's????

 

If you change your head and want to go with 1.6 roller rockers I wouldn't go with the 305 torquers. I have read that the S/R 's flow numbers suck as it approaches .500 lift (of course any head's flow numbers at .500 lift are FAR better than our stockers!!) I know if I was head swaping, I would go aluminum. Just too many advantages to ignore. AFR puts out some good heads (for some good dough) or going with a used set of vette heads and porting them out with a 3-angle valve job is always a good option as well.

If you are keeping the stock heads in place, I wouldn't go any higher on the lift than the numbers you quoted. Sure don't want pistons to hit those valves!! makes me sick lust thinking about it.

Matt

 

with that cam an LT4 cam on an LO3 i woudl say stick to 1.5 rockers. teh 1.6's will put it into that lift area that you start getting air flow issues, which leads to a lot fo tuning issues.
full rollers are always best, but they $$$$$.
as far as the heads go, torquers are the economicla choice, they flow very good and are a bargin price.
voprtechs are great heads, you will have to spend a little extra on the manifold, but it is worth it. try to get them shaved down to a 56 or 57cc chamber to try to grab a little extra compression.
if you are gonna go aluminum, i woudl say look at he 60cc edelbrocks. they are a very good flowing head and teh 2.02/1.60 valves will work very well on a 305. i woudln't suggest shavign them because the larger valves are already gonna be close enough to the walls, you woudln't want to put them lower in teh hole and mess up your air flow. the aluminum will also allow you to run a little more spark advance and drop about 60lbs off of the car.
afr's are nice but $$$$$$$

later
tim

 

What about E-Tec 170 heads? - they're an improved aluminum Vortec design.