Hoping this isn’t off topic/mudding up your thread (I can delete it/get it moved if so)
Have you decided on what type of cylinder heads you will be using for your SBC engine? I was hoping to pick your brain a bit on what you felt would be better for our (woodgas) applications. From what I’ve been reading you cannot beat the vortec 350 heads if you don’t go aftermarket. Whats your thought between vortec 350, 062 castings and vortec 305, 059 castings.
from what I’ve read/ seen with my own eyes (i have both sets of heads in the garage waiting to be installed when I figure out which would be better ).
both 305 and 350 have the same exhaust valve size 1.50
however 350 has slightly larger intake valves 350 = 1.94 vs 305 = 1.84
350 has bigger combustion chamber than 305 ( 350 = 62cc vs 305 = 58cc) so 305 heads would boost the compression up compared to the 350
not sure what the compression would be on 305 heads but guys who have done it state cannot drive with pump gas but ok with 93 octane.
350 has the “kidney” “fast burn” combustion chamber design whereas 305 has D shape standard combustion design.
I got the flow #'s here for the two heads http://users.erols.com/srweiss/tablehdc.htm#Chevy
but It all looks like jargon to me and can’t interpret/compare the two to heads.
To me the 305 heads (with DIY porting) would seem to be a good choice if one was willing to sacrifice the use of pump gas for some more compression (would this help woodgas?) however I don’t really want to throw a set of 305 heads on the engine if 350 heads will give the same results but allow pump gas to be used. As it stands I only really use gas to start the truck and for slight boost. I would use 93 octane with 305 heads if I only needed it for starting the engine.
Another area I’d like to hear your thoughts on relative to this is cam selection. When I got the vortec 305 heads I also grabbed the cam, roller lifters, timing gear from the same engine etc. Would you change the cam at all to take more advantage of the higher compression?
Whats your thoughts?