[robbiesmechanic]

i bought this amazing 84 gmc pickup for $100. www.cardomain.com. it had a worn out 305 in it, and i am in the middle of an engine swap for a 350. i have bought 2 sets of 350 heads and neither one was what they were supposed to be. i have a set of 1.94 valve 305 heads. i was wondering if this would surffice until i had the money to buy a good set of 350 heads? the specs of the engine are: stock crank turned .10 on main and rod.., 495 lift comp cam with 295 duration intake/exhaust. new lifters and springs to match cam. new stock bore, 4 valve flat top summit pistons with new rings. and a built quadrajet 4 barrel. this is just for the street. will this work for time being?

[oldbogie]

Originally Posted by robbiesmechanic

i bought this amazing 84 gmc pickup for $100. www.cardomain.com. it had a worn out 305 in it, and i am in the middle of an engine swap for a 350. i have bought 2 sets of 350 heads and neither one was what they were supposed to be. i have a set of 1.94 valve 305 heads. i was wondering if this would surffice until i had the money to buy a good set of 350 heads? the specs of the engine are: stock crank turned .10 on main and rod.., 495 lift comp cam with 295 duration intake/exhaust. new lifters and springs to match cam. new stock bore, 4 valve flat top summit pistons with new rings. and a built quadrajet 4 barrel. this is just for the street. will this work for time being?

Depending on what your using for a head gasket and how much the block's been decked, if any, this should pull about a 10.2 to 1 compression ratio. The cam has a lot of duration if this translates into mucho-grande overlap and a late closing intake, the dynamic compression should be around 8.6 or so. You should be able to get away with this from an iron head and 91 octane. Ported with big valves, you may discover that you don't need to replace the heads. Modified 305 heads on a 350 were always sort of a poor man's Vortec long before L31 Vortecs existed.

Bogie

[F-BIRD'88]

Which "305 heads" do you have? casting number. They are not all created equal.

Some of the 305 heads have a very restricted exhaust port. "434" casting has this.

The 416's are the best 305 head to start with. Even these need a full port effort.
It can be done and done well if you are willing to do the work.
What cam is that specificly? It seems big for a pick up truck.

[maxpower_454]

I didn't think there were any 305 heads made with 1.94 valves but maybe I'm wrong or they were done afterwards

[Hippie]

Originally Posted by maxpower_454

I didn't think there were any 305 heads made with 1.94 valves but maybe I'm wrong or they were done afterwards

You "think" correctly......