[accontrol]

I notice that many 350 engine will have a set of 305 head on them ?
is that for the extra compression ..I wonder will they flow as well as a
350 head ?

I see this as quick upgrade for performance.. is it realy ? the valve size
in a 305 head is small..

i ned somme advise on this
thank you

acguy

 

[o67]

most of the round trackers used to use the 305 ho heads on the motors to raise compression 58cc heads.the hos had bigger valves than the regular 305heads also .you would be better off with the 350 4 barrel heads in my book.i have never used a set but they say the vortecs flow better than the double humps

 

[Mike Feudo]

o67 pretty much said it. If you want a real torque motor it works well if you want any kind of high RPM performance you need bigger runners.

 

[BillK]

ac,
Alot of the big rebuilders do this too because of the availability of good 305 heads. They actually make a piston for this application that has a big dish to keep the compression down to stock.

 

[Motorhead62]

You can take a 305 head, add big valves, unshroud the valves, do some porting work in the bowl and exhaust.

Then use a set of D-dish Keith Black pistons on a zero decked block and get great quench.

An easy way to build a budget semi-efficent engine as far as the combustion chambers are concerned.

:thumbsup:

 

[camaro_fever68]

IMO, unless you getting the heads and machine work for free, you are better off staying away from 305 heads. The vortec heads are the best flowing production head ever casted by Chevrolet. They work best as cast with the stock 1.94 valves. You can get a vortec dedicated intake from Professional Products for $130.00 that is called a Crosswind and it performs as good as the Perfomer RPM air gap is the same style. You are limited by camshaft lift on the vortec due to the size of the valve guide but I think Comp now makes a spring good to .550 lift without machine work. If you're reheading your engine on a budget, go vortec. It has 170cc runners and 64cc chambers.