Hot Rod Forum banner

1 - 20 of 21 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter #1
Ok, so I posted my thread about 3 days ago on having a 307. In listening to the responses I've gotten, you have thoroughly proved that I don't have a 307 on my hands.

The real reason for writing this is to ask, would it be possible to put a 350 crank into a bored out 307 and make it work?

The bore measures a 4.0 inch bore, like a 350, and the crankshaft flange, is not a 307 crank, but a 350 according to an article in car craft. I went out to check the crankshaft flange like someone said to, then looked at the picture, and distinctively remembered the notch in the top of the flange, which is only on the 350 crank. Tell me what yall think.
 

·
You got a leaky spark tube...
Joined
·
2,854 Posts
You cannot bore a 307 anywhere near far enough to get one out to a 4.00" bore. The crankshaft has a casting number, find it and look it up. If the block has not been decked then there should be some numbers on a small pad on the cylinder head deck surface at the front of the engine above one of the coolant inlets from the water pump. They're stamped in, not cast. If you can read those post them here. Also, degrease the casting number very well and see if you can take a good picture then post that as well. Is the engine a two bolt or four bolt main?
 

·
Save a horse, Ride a Cowboy.
Joined
·
5,122 Posts
Man, you already have a 350. I explained it in detail in the other thread. :rolleyes:

Are you just hypothetically asking if a 350 crank will go into a 307?

Why would anyone do that? It would cost about $ 700 to have a set of custom piston made.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #4
xntrik said:
Man, you already have a 350. I explained it in detail in the other thread. :rolleyes:

Are you just hypothetically asking if a 350 crank will go into a 307?

Why would anyone do that? It would cost about $ 700 to have a set of custom piston made.
well i know but what i dont know is how to explain the casting number being a 307 casting number, while it has a 350's bore and crank...
 

·
Premium Member
Joined
·
3,519 Posts
bigdome16 said:
well i know but what i dont know is how to explain the casting number being a 307 casting number, while it has a 350's bore and crank...
307 does not have the same bore as a 350. 350 is 4 inches, 307 is 3.875...

K
 

·
Registered
Joined
·
16 Posts
Discussion Starter #6
killerformula said:
307 does not have the same bore as a 350. 350 is 4 inches, 307 is 3.875...

K
ya thats whats throwin me off so bad. its a 307 casting, but it has a 4 inch bore.
 

·
You got a leaky spark tube...
Joined
·
2,854 Posts
Once again...
If the block has not been decked then there should be some numbers on a small pad on the cylinder head deck surface at the front of the engine above one of the coolant inlets from the water pump. They're stamped in, not cast. If you can read those post them here.
 

·
Registered
Joined
·
1,304 Posts
Blazin72 said:
You cannot bore a 307 anywhere near far enough to get one out to a 4.00" bore. The crankshaft has a casting number, find it and look it up. If the block has not been decked then there should be some numbers on a small pad on the cylinder head deck surface at the front of the engine above one of the coolant inlets from the water pump. They're stamped in, not cast. If you can read those post them here. Also, degrease the casting number very well and see if you can take a good picture then post that as well. Is the engine a two bolt or four bolt main?
if it has a casting number 3970020, you can bore it to 4 inch
 

·
Registered
Joined
·
1,304 Posts
bigdome16 said:
ya thats whats throwin me off so bad. its a 307 casting, but it has a 4 inch bore.
if it is a 307 casting with a 4 inch bore then its a 327. the casting # 3970020 list as 307,327 and 350 if thats what your # is
 

·
Analog man in a digital world.
Joined
·
2,252 Posts
runn141 said:
believe it or not its true
I believe it. I've been told that some bomber and street stock dirt track racers are doing it for "claimer" motors, they bore a 307 block to 4 inches and use 267 or 305 cranks and rods with std. bore 350 pistons people have taken out of 350's they bored out and then throw small chamber 305 heads on them. They run good........... for a little while, they don't have much in them and if it gets claimed they aren't out much and the other guy didn't get much.

You can also stroke a 307 using a 350 crank, 400 rods and the 307 pistons........... don't know why anyone would bother but it CAN be done. :rolleyes:
 

·
Registered
Joined
·
3,518 Posts
Not to cause a pi----- match here but according to Mortec casting #3970020 is a 307 only, 69-73 2 bolt block. There are no 327/350 listed with that number. Where are you getting your info ? And to Bigdome if you are that concerned then take it back and get a REAL 350 that has a 350 casting number, Sooooo much easier.
 

·
Registered
Joined
·
1,304 Posts
327NUT said:
Not to cause a pi----- match here but according to Mortec casting #3970020 is a 307 only, 69-73 2 bolt block. There are no 327/350 listed with that number. Where are you getting your info ? And to Bigdome if you are that concerned then take it back and get a REAL 350 that has a 350 casting number, Sooooo much easier.
Ziggy's Chevy V-8 Parts Finder, casting numbers for blocks,cranks & heads
 

·
Registered
Joined
·
1,304 Posts
Hippie said:
I believe it. I've been told that some bomber and street stock dirt track racers are doing it for "claimer" motors, they bore a 307 block to 4 inches and use 267 or 305 cranks and rods with std. bore 350 pistons people have taken out of 350's they bored out and then throw small chamber 305 heads on them. They run good........... for a little while, they don't have much in them and if it gets claimed they aren't out much and the other guy didn't get much.

You can also stroke a 307 using a 350 crank, 400 rods and the 307 pistons........... don't know why anyone would bother but it CAN be done. :rolleyes:
ive also heard of dirt trackers having 400 blocks sleeved and using 283 size pistons. i dont know why though
 

·
Analog man in a digital world.
Joined
·
2,252 Posts
runn141 said:
ive also heard of dirt trackers having 400 blocks sleeved and using 283 size pistons. i dont know why though
That one I hadn't heard.............
 

·
Registered
Joined
·
16 Posts
Discussion Starter #19
327NUT said:
Not to cause a pi----- match here but according to Mortec casting #3970020 is a 307 only, 69-73 2 bolt block. There are no 327/350 listed with that number. Where are you getting your info ? And to Bigdome if you are that concerned then take it back and get a REAL 350 that has a 350 casting number, Sooooo much easier.
yup weve pretty much got that figured out...i wasnt concerned, i dont really care that much because im probably gonna just buy a new car with 305/327/350, just whatever comes my way...but if i can, i want to finish this project up, or sell it.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #20
bigdome16 said:
yup weve pretty much got that figured out...i wasnt concerned, i dont really care that much because im probably gonna just buy a new car with 305/327/350, just whatever comes my way...but if i can, i want to finish this project up, or sell it.


take that back, i do care....just not that concerned, its just a side project while im not at school. just wanted to get some experienced help with it because this is my first rebuild.
 
1 - 20 of 21 Posts
Top