[48chvsb]

have a block bored .30 over want to put 305 or the 350 heads on it which is a better idea and what pistions woudl i need ?

Sorry new to all this .

Thanks

[F-BIRD'88]

What are the casting numbers on your head choices? What are you trying to achieve.?

[48chvsb]

I have 305 "416" and 350 "624" and i just want to make due with what i have.

But make it a bit better .

[F-BIRD'88]

Home port the 305 heads to increase the port flow and stick them on the 350.
The more you port them the better they will work.
They are a better head than the 624's but need the porting to bring out the power.

Install larger 1.94 intake valves with a new valve job in the 416 heads for even more power.

The ported 416 heads have smaller combustion chambers for more compression on a 350.

Street machine?, truck? whats the vehicle and purpose?

[FastOrange]

First off, Whats your short block? 350? 400? 327?

[SSedan64]

You need to give more details.
What Block do you have? 350?
Intended use of engine?
What vehicle is Engine going in etc..?

[48chvsb]

350 sbc. and its a 48 chevy pickup on an s-10 frame bagged. Mainly car shows. and here and there driving not much racing if not at all .

[48chvsb]

350 sbc
street rod
1948 chevy pickup on an s-10 frame, bagged.

Thank u

[ap72]

Use stock dished 350 pistons with the 305 heads and a cam with about 220 duration and a narrow. Lsa. Its a cheap combo that produces good mid range power and has a nice rumble at idle. I like the 274h06 cam for this type of build. Elgin sells a cheap version and it gives a nice rumble for the shows but will work with most stock drivetrains.

Fbird gave good advice on the heads, but for your app larger valves aren't necessary imo. Save that money and put it towards a used performer intake and some good long tube headers.