Just wondering...I know the head will physically bolt on, but will there be any improvement in performance? They're 64cc chambers with 1.94 intakes. I would assume an increase in power from higher compression and more flow... any input would be appreciated. Yes, I know the 305 is a loser but it's all i've got in my 69 while i build my 383...

I think 305 heads are about 58-60cc, so you'll loose compression. Some, if not all, came with 1.84" intake valves, so the 1.94 valves may be too big...not sure.

Overall, not a good idea. Save your money and time.

If you could mill the heads down to 58cc's you would keep the stock compression. If the 305 had dished pistons your in the 8.25 to 1 range. If it was the (L-69) 305 HO engine with flat tops you would have 9.3-9.5 to 1 with the 58cc heads. 1.94 valves with the appropriate camshaft would probably be alright.

Thanks for the responses. You're absolutely right though...why waste my time? Dont' know what I was thinking, but I know i'm desperate for more power. I'm surprised at how well the 305 is holding considering the 4.56 gears in the 12 bolt.....

well i know this may be an old post but i was looking for things ppl have said about the 305 and i have a 305 in my chevelle and its good to see someone else w/ a 305. i have planned to put a holley 600 on it and a full exhaust w/ headers and xpipe and then a cam..what ya guys thing...then i could use them parts for my 406 after i build it.


aaron

im running a 305 in my 70 Malibu, i have a TH-350 and a 10-bolt open rearend with 2.73s.

the bottom end and valve train are completely stock to my knowledge. its a 305 out of a 89 Iroc Camaro but the TPI was stripped of and an Edelbrock Performer intake and a holley 4bbl carp are in its place. an accel HEI kit and plug wires fire the sparks. the exhaust runs through a set of Hooker Competition headers and then continues through a full 2.5 dual exhaust system, no h-pipe, and then through a pair of flowmasters and and tailpipes turn down under the bumper. the cam is stock for all i know.

the car ran a 10.482sec 1/8 mile with a VERY BAD reaction time of 1.48 seconds and a the MPH was 66.85.

this is a totally untuned 305 in a daily driver.