Will the 240 crank and rods work on the 300 block?? Any information on porting these heads? What size are the combustion chambers for comp ratio reasons?

 

The 240 and 300 are the same block. The main differences being the crank/rods/pistons. As for porting the heads, I found an article the other day on porting the BB6 and SB6 heads, but they had no pictures. Otherwise you can just use a regular porting guide (http://www.sa-motorsports.com/diyport.htm). IIRC the stock combustion chamber on a 240 is 68cc.


-=Whittey=-

 

Same pistons, different crank, different rods. The 300 crank can be used with 240 rods and short pistons, to make a long rod motor. And yes, you can just drop a 240 crank and rods into a 300, but the combustion chambers on most older 300-6's were 74cc, vs 64-68 for the 240.

 

The pistons on a 240 had a shorter compression height and the earlier ones had a 0.9122 pin diameter versus the later 240 (and all 300) pin diameter of 0.9752.


-=Whittey=-

 

240 pistons aren't the same as 300 pistons. The 300 uses a 300 specific piston(a 351W piston can be used with some pin sizing work, in my setup, I ended up with floating pins) while the 240 uses a 302 piston.
Evan