307 crank in 350 block???

Took an engine apart for a friend (350 sbc) and found out the main and rod journals are shot. Took to the machinist to machine and he thought something looked strange so he looks at the numbers and determines the crank is out of a 307. Why would you do that?? I am ***uming we will want to find a 350 crank to replace it with?? This will be a street driven OT '72 Nova. Thanks-

 

307 crank + 350 block = 327

 

350 block with a 307 crank makes a 327, his pistons will not work will a 350 crank, they will be 327 pistons

 

what you have their is a 327....307 and 327 have the same stroke but the 350 and 327 have a 4''bore..so that makes 327

 

Basically a 3.25 stroke crank...the same stroke as a 327...so if they used the correct pistons with the 327 compression height, your friend has a 327.

If he wanted, he can use 350 pistons with the desired overbore, and a 3.48" stroke crank, and then he'll have his 350....

 

what is the casting number of he block? casting date? there were a few large journal 327s made at the end of production

 

hey i wonder if any one said ...its been changed to a 327?

just messin'

check the pad on the front p***enger side of the block..that will tell you more than the casting numbers on the back of the block on the rear drivers side

 

The $50 engine in my 57 Chevy truck is a '74 Monte Carlo 307 block, stamped rebuilt in 1976. It has 2.02/1.6 '882' heads, and an early crankshaft with the press-on dampener. Weird stuff!!

 

block is a 3970010 which if I understand correct is a 69-80 350??
pistons are trw L3022F +.030, so 4.030 bore (.030 over 350)??
rod bearings are clevite 77 CB663P .010, havent checked those numbers but am guessing that have to be the correct ones for the 307 crank
heads are 882, not that that makes any difference, with screw in rockers and guide plates, looks as if someone has done some port work also...
cant find any numbers on the cam, so ????

Is there any benefit to the 307 crank???

 

307s were made from 68-73 so that is odd...

 

3970010 was also a 1968 327 if I remember correctly

 

it was used for the 350, 327, and 302 in 68/69

 

that block could have been 327 or 350 , the pistons are 350

do we really know for a fact that crankshaft is 307?

 

If the block is a 4 bolt main then it was parts put together,,the 882's flow well with lower compression,,,but all of it bolted together is a great great combination.
I'd run a 480 lift dual pattern cam ,,around 230/234lift.

 

actually the 307/327 used the same number in some cases too

 

crank is at machine shop right now so unsure of its casting # right now...

 

block is a 4 bolt, so it has to be a 350 block, correct???

 

the motor may just be a late production 327. either way, build what ya want

 

I have a big journal 327 from 1968 with the casting number 3914660. Check Mortec.com and you can narrow it down somewhat.

 

Why not just keep it as a 327? With the right cam and heads, it can be a very mean motor with lots of RPM's.

 

I had all the parts to do the 307/327/350 at one time. I say rebuild it and run it, 327 sounds better than 350 anyway!

 

Not necissarily, '69 302 with that casting were 4-bolt mains.

 

You open a 350 and find a "4 bolt" 327...and say this needs correcting.
I would be buying LOTTERY TICKETS and doing backflips...

I know...it all needs to be rebuilt anyway...but still cool to find.
Obviously I'd go with the 327.