Which do you guys think would be better for a 305 LG4 with 9.6:1 compression, and a Comp Cams Extreme energy cam:
int exh
Gross Valve Lift: .495 .502
Duration: 270 276
Duration @ .50 218 224
110 Degrees of Lobe seperation.


World Castings S/R Torquer Heads
or
Chevy truck L31 Vortec cast iron heads, GM P/N 12558060?

 

Probably port and put bigger valves in your 416's that are on it now, at least cost wise.

 

i wouldn't be putting the time, effort, or jack into a 305 (as a rule) but between the 2 heads you listed i'd go with the WP S/R heads.

 

Check this link for more info on your existing LG4 416 castings:

https://www.thirdgen.org/techbb2/sho...hreadid=150604

They are good heads from what I understand, and have great potential with some porting/polishing effort. Also check Sitting Bull's sig - he has a link in his sig on porting heads.

I have a set of the 416 heads from an LG4, and after reviewing the how-to's, and looking at the heads and how little has to be done with them, I'm going to port mine myself to put on my 305, and I've never done it before.

Also check out the how-to at
http://www.sa-motorsports.com/diyport.htm

$40 for the porting kit, $40 for an electric grinder, and some brow sweat may save you a ton of cash for other things.

 

thats a pretty big cam for a 305? don't you think..?

 

The L31 heads are excellent power makers. There's a few modifications that need to be done though to make them work properly however. Do you need to be emissions compliant?