Chevy Nova Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
5,781 Posts
Discussion Starter #1
Is it at all possible to put a 3.48" stroke crank from an old 350 in my 307? I know that there will be need of a rebuild, stroker or not...I know I can't get a 400 crank, but will the 350 fit without hitting the heads? do they make special pistons? if not, maybe I'll do the 327....or keep the 307...Ideas????????
 

·
Premium Member
Joined
·
572 Posts
The 307 shares the same bore as a 283, so it's kinda already like having a stroked 283. I think aftermarket pistons would have to be custom made for this combo, unless you used the stock 307 piston with 400 connecting rods on the 3.48" 350 crank. It would work, could be done cheap, just don't spin it real hard or use to much nitrus....:D :D

KenDog
 

·
Registered
Joined
·
5,781 Posts
Discussion Starter #3
hehehe, nitrous. some guy in a little tuner a while back used so much, he blew the engine....showing off doesn't cut it when you can't keep your bluff!
 

·
Premium Member
Joined
·
31,194 Posts
Check your 307 mains to be sure they are large like 350 I think 70 up 307's have small journal cranks and 350 don't fit.Some the other guys here might have more info on this.

Paul
 

·
Premium Member
Joined
·
10,210 Posts
From the mortech website

Mortec Website said:
Gen.I, "Small Journal"
265...Mains-2.30"-Rods-2.00"
283...Mains-2.30"-Rods-2.00"
302...Mains-2.30"-Rods-2.00"
327...Mains-2.30"-Rods-2.00"

Gen.I, "Medium Journal", includes "Vortec" 305 and 350 thru '98
262...Mains-2.45"-Rods-2.10"
267...Mains-2.45"-Rods-2.10"
302...Mains-2.45"-Rods-2.10"
305...Mains-2.45"-Rods-2.10"
307...Mains-2.45"-Rods-2.10"
327...Mains-2.45"-Rods-2.10"
350...Mains-2.45"-Rods-2.10"

Gen.I, "Large Journal"
400...Mains-2.65"-rods-2.10"
http://www.mortec.com/journal.htm
 

·
Registered
Joined
·
1,047 Posts
3.480"

If I'm not mistaken:confused: I think the 307 has the same stroke as a 350:eek:

RED67:chev:
 

·
Registered
Joined
·
7,257 Posts
No, it has the same stroke as the 327. The 350 crank does make a 330/331 stroker. I thought this through and realized a 350 had more cubes, a bigger bore (to allow for bigger valved, better heads) and was cheaper to build. I do have a set of stock 400 rods if you want them to use in this build up.

I'll see if my old post on this subject wasn't deleted from the archives.

Kev
 

·
Premium Member
Joined
·
8,405 Posts
RED67 said:
If I'm not mistaken:confused: I think the 307 has the same stroke as a 350:eek:

RED67:chev:
You are thinking of the 305.
 

·
Registered
Joined
·
5,781 Posts
Discussion Starter #9
yeah, the 350 has the 4.000, the 307 has only a 3.875 bore. also, the 350 has a 3.48" stroke as opposed to the 307's 3.25" I was wondering..... is there a way I can get custom made connecting rods? A real interesting thought hit me: what if I can fit a big block 4.250" stroking crank in it??? Of course, that would need extremely short rods... but being me you care about that as much as cats care about you.....
 

·
Registered
Joined
·
7,257 Posts
No, a big block crank will not come close to fitting in a small block. Take 400 rods, a 307 crank and 283 pistons and you get short rod 307. Take 400 rods, a 350 crank and 307 pistons. You end up at a 8.96 deck height. That means you need to deck the block AT LEAST to 9. That still leaves you with crappy quench (.068 down .040 + a .018 shim gasket), but it'll be okay. You'd want to cut it down to below "zero" deck to make it run better. 283 pistons will pop out of the block. You'd be left with a theoretical 9.11 deck height, meaning that if your block is close to the often quoted 9.025, you'll be about .14 out of the hole.

Kev
 

·
Premium Member
Joined
·
10,210 Posts
supernovanator said:
A real interesting thought hit me: what if I can fit a big block 4.250" stroking crank in it???...
My answer to that is you cant:)

I believe the overall length of the crank is too long, the journals are too large, and the stroke is too long to fit within the confines of a SBC block...
 
1 - 11 of 11 Posts
Top