So I bought a sbc 305 last summer put it in my 1981 Monte Carlo, it's been running fine but need to rebuild my heads and was wondering if they were worth rebuilding or not they are 350 heads off of an early 1970's block and I beat 350's and other motors with my lil 305 haha but the # on the heads are 3986339x. I don't know if the block is bored out or not but seems like it has a high compression ratio and the block is a 1988 chevy 305 block out of a Monte Carlo (that's what the guy that I bought it from said) and was thinking about going with vortec heads or camel hump heads just cuz I might be able to get them cheaper than what I would pay for rebuilding my heads and what compression ratio would be the best for my 305? Thanks
What heads will give me the most power out of my sbc 305?
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Re: What heads will give me the most power out of my sbc 305
305s had higher compression heads then the 350. 305 heads on a stock 350 will gain you compression but 350 heads on a 305 wont really help you out. If you put a camel hump head on a 305 those big valves are gonna have a fight with that small bore. Best bet is to switch back to some worked 305 heads or just get a 350. Bore is probably stock since a 305 in any configuration of bore or stroke is so limited that a mild 350 will out power a fully built 305
305s had higher compression heads then the 350. 305 heads on a stock 350 will gain you compression but 350 heads on a 305 wont really help you out. If you put a camel hump head on a 305 those big valves are gonna have a fight with that small bore. Best bet is to switch back to some worked 305 heads or just get a 350. Bore is probably stock since a 305 in any configuration of bore or stroke is so limited that a mild 350 will out power a fully built 305
Re: What heads will give me the most power out of my sbc 305
The heads you have are small valve (1.72), large chamber (74cc) 307 heads. I would guess your CR is now in the 8s or even 7s. Pretty much anything will be an improvement. Any head that's considered a "performance" 305 head would work well. Even something like the 283 Power Pack heads would run pretty well (but lack accessory bolt holes on the ends). Don't forget, there is a 305 Vortec version. Small chamber 327/350 heads with 1.94" valves will suffer from shrouding issues.
Honestly, I wouldn't recommend spending any money to build/rebuild a 305. You'll be way farther ahead to just start with a 350. They cost the same, or even less to go through.
The heads you have are small valve (1.72), large chamber (74cc) 307 heads. I would guess your CR is now in the 8s or even 7s. Pretty much anything will be an improvement. Any head that's considered a "performance" 305 head would work well. Even something like the 283 Power Pack heads would run pretty well (but lack accessory bolt holes on the ends). Don't forget, there is a 305 Vortec version. Small chamber 327/350 heads with 1.94" valves will suffer from shrouding issues.
Honestly, I wouldn't recommend spending any money to build/rebuild a 305. You'll be way farther ahead to just start with a 350. They cost the same, or even less to go through.
Re: What heads will give me the most power out of my sbc 305
305 heads are getting harder to find, best oe heads are the 14014416 from a Ho camaro/firebird mid 80s cars that have 58cc chambers and pack 1.80/1.50 valves. A basic port match, and your good to go! Look close at the engines, I pulled my 416s out of an 84 caprice wagon.... Hope this helps!
305 heads are getting harder to find, best oe heads are the 14014416 from a Ho camaro/firebird mid 80s cars that have 58cc chambers and pack 1.80/1.50 valves. A basic port match, and your good to go! Look close at the engines, I pulled my 416s out of an 84 caprice wagon.... Hope this helps!
Re: What heads will give me the most power out of my sbc 305
Not gonna swap a 350 in it don't have that kinda cash for it right now and it is my daily driver, so the heads from a firebird will work pretty good? Or the vortec 305 heads? Which will be better? And I was just askin about the heads so please don't tell me to swap another engine in it when mine is fine for now thanks
Not gonna swap a 350 in it don't have that kinda cash for it right now and it is my daily driver, so the heads from a firebird will work pretty good? Or the vortec 305 heads? Which will be better? And I was just askin about the heads so please don't tell me to swap another engine in it when mine is fine for now thanks
Re: What heads will give me the most power out of my sbc 305
You'd have to get heads from another 305 cause they have 58CC and some smaller combustion chambers.
If you go with larger cc it'll kill your compression.
Look for the swirl port or 4 barrel or HO heads 416s as mentioned above
Look here for casting #s
http://www.nastyz28.com/sbchevy/sbch.php
Hope that helps.. 8)
You'd have to get heads from another 305 cause they have 58CC and some smaller combustion chambers.
If you go with larger cc it'll kill your compression.
Look for the swirl port or 4 barrel or HO heads 416s as mentioned above
Look here for casting #s
http://www.nastyz28.com/sbchevy/sbch.php
Hope that helps.. 8)
Re: What heads will give me the most power out of my sbc 305
There is the old saying "run what ya bung" that 305 should serve you well... Letting you get the funds together for a good swap... I would be interested in what the casting number is on the block. Just to verify displacement. 416s are the way to go, everything else you already have will bolt up, vortecs do flow better but have bigger chambers and need a different intake and rocker arms, and valve covers....
There is the old saying "run what ya bung" that 305 should serve you well... Letting you get the funds together for a good swap... I would be interested in what the casting number is on the block. Just to verify displacement. 416s are the way to go, everything else you already have will bolt up, vortecs do flow better but have bigger chambers and need a different intake and rocker arms, and valve covers....
Re: What heads will give me the most power out of my sbc 305
The number on back of the block is 14088551
The number on back of the block is 14088551
Re: What heads will give me the most power out of my sbc 305
That casting # is a 1986-92 305
http://www.nastyz28.com/sbchevy/sblock.php
That casting # is a 1986-92 305
http://www.nastyz28.com/sbchevy/sblock.php
Re: What heads will give me the most power out of my sbc 305
Been playing around this morning, best guesses say...
88 std 305 dish pistons
current heads (74cc chamber) 7.71:1 compression
14014416 heads (58cc chamber) 9.1:1 compression
14022601 heads (53cc chamber) 9.6:1 compression
88 HO 305 flat top pistons
current heads (74cc chamber) 8.25:1 compression
14014416 heads (58cc chamber) 9.9:1 compression
14022601 heads (53cc chamber) 10.59:1 compression 8)
The 14022601 (601) heads are also an early 80s "perf" head for the 305, they dont flow as well as the 416s....
you should be able to find one of these close to you, I looked for 6 months before I found my 416s but there was a few sets of 601s i passed on, mostly because i had the time to wait for what i wanted.... There are some aftermarket 305 heads, World, Trick flow.... but are gonna be way more $$$
Been playing around this morning, best guesses say...
88 std 305 dish pistons
current heads (74cc chamber) 7.71:1 compression
14014416 heads (58cc chamber) 9.1:1 compression
14022601 heads (53cc chamber) 9.6:1 compression
88 HO 305 flat top pistons
current heads (74cc chamber) 8.25:1 compression
14014416 heads (58cc chamber) 9.9:1 compression
14022601 heads (53cc chamber) 10.59:1 compression 8)
The 14022601 (601) heads are also an early 80s "perf" head for the 305, they dont flow as well as the 416s....
you should be able to find one of these close to you, I looked for 6 months before I found my 416s but there was a few sets of 601s i passed on, mostly because i had the time to wait for what i wanted.... There are some aftermarket 305 heads, World, Trick flow.... but are gonna be way more $$$
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