some guy told me to use 350 heads on my 305, arent they too large and would cause the engine to bog? what would be a good size to switch with? 307, 327? if not when i change my valve seals is there any thing i can do to impove performance? ie. rockers or push rods?
thanks for any help
(limited budget right now)

 

some guy might be right but it would depend on the heads and waht you have as well as what you're trying to do. a little more info would go a long way, but a WAG is that it wouldn't be a good idea.

 

Use 416, 601, 081 heads on a 305. They are 305 heads.

 

350 heads + 305 engine = crappy compression

 

Plus alot of 350's came with 1.72" valves and the intake ports are smaller.

 

Exhaust.

Until you do that, no amount of head pounding is going to make a lick of difference.