I have a 307 sbc totally stock, wondering if I could put a 350 crank. What would be involved in putting this crank in? and what displacement would this crank change the 307 to?
Just leave it a 307 or a get a 350. To much money wasting.A 307 crank will fit in a 350 for a 327. but why lose the cubes? If yo start changing out cranks, get a stroker and build a 383.
Well a 283 and 327 share the same 3.25" stroke. I believe the 283 and 307 have the same 3.875" bore. You'd probably have to clearance the block for the extra 1/4" stroke of a 350 crank, special pistons... all for probably somewhere around 340 cubes. it seems a 350 would be much easier and cheaper to accomplish. Or just build the 307 and be happy.
Theres a big article on crankshaft interchanges in the January issue of Hot Rod magazine. Page 116. Good luck.
A 283 is a 3.00" stroke, a 327 is a 3.25" stroke. The 283 and 307 share the same bore. The 307 and 327 share the same stroke.
Put your 307 crank in a 350 block for a 327. Both are large journal and parts are shelf items. Smokey
Bore it out to 4" and your there. Better have the block sonic checked to see if there is enough meat to do it or you'll just waste a block if the boring bar punches through to water on the last p***. Or worse yet ***emble it and have a couple of cylinders crack when you fire it up. Frank
Boring anything 1/8"(.125") is extreme and requires the use of a sonic checker in order to determine the thickness of all the cylinders to make sure there would be sufficient meat left. The earlier small journal blocks were often found to contain enough m*** to sustain such punishment from the boring bar(but at the time they used a small ball peen hammer to sound the bores before the final p*** with the bar), the later blocks never did (that I know of). The 307 is a large journal block, they came out in '68, '67 in 350 form in the Camaro. Your block will go 1/16"(.060") no problem.
There is nothing wrong with a 307. They got a bad name for some reason. With small 4 barrel carb and a RV/torque cam they are good engines. But, sayin' 307 just sounds lame. I stuck a 307 in an 80 Malibu and it hauled a family of four and pulled a pop-up camper just fine. Smokey
Not to hijack, but just so I know... A 283 crank in a 327 makes a 301 right? Or Chevy called it the 302... I had a brain-fart thinking the 283 and 327 shared the same stroke...
But why would we get a 350 block and just use the block for a 327 rather just build the 350, rite? We have a 307 block and a 400 laying around. The 307 is complete and the 400 is jsut the bare block but i just came across some complete heads for free. Where thinking me building either one for our 68 C-10. 68Chevy is my dad we will get pictures up soon of the truck. But what would you rather see in the truck the 400 or the 307?
as others have said , i really doubt that you could go past .060 safely on a 307 if you want a 307 , and there is nothing wrong with a 307 , rebuild the 307 with the stock crank and the smallest bore you can get by with...maybe .030 , .040 or the maximum .060 if you have to if you want a 350 , find a 350 and rebuild it
Here are some pictures of the truck. It currently has a 305 with a holley dominater intake with a 650 cfm secondary vacuum carb. We also put a petronix kit under the cap other then that it just has a TH-350 and everything else is stock
Here's an extract from http://www.mortec.com/borstrok.htm CID Bore Stroke 307 3.875" 3.25"</o></o> 327 4.000" 3.25"<o></o> 350 4.000" 3.48"<o></o> 383 4.000" 3.80"<o></o> 400 4.125" 3.75"<o></o> 427 4.125" 4.00" 350 crank will give 328 cubes and a 4" (sbc 427) crank gives you 354 cubes. If somebody could run some numbers in a computer dyno program it might be interesting.
I'd never attempt a .125 overbore on a 307 block, and anything less, combined with a 350 crankshaft, would leave you with an engine that you'd have to buy an expensive set of oddball pistons for. A set of 3 7/8 X 3.48 pistons would cost more than just finding a garden variety 350 and going in that direction.
The factory cams used in 307's were "soft", a lot of them went flat in no time. I think THAT is what started their bad reputation. A LOT of guys build their 307 however. Now, theres a machinist over on Hotrodders.com that claims to bore 307's to 4" bore all the time, and uses standard bore 327 pistons. Of course that kills ANY future overbores. Or, take a 307 block and bore it .060 over (pistons are available on that auction site), take a 262 3.10" stroke crank (also on that auction site), and balance the rotating ***embly. Now, you have a 301.6005 CID motor, of course it will have cast, flat top pistons, and a cast crank; no big deal, it'll only rev to the valve train limits anyway. Butch/56sedandelivery.
A 350 crank will only fit after a bunch of grinding.You will have to use 400 rods to make it all work.You can use inexpensive 307 pistons but will have the extra cost of grinding,fitting,and balancing the crankshaft.You will end up with a 333 if you bore it 30 over.
Combination's abound here, cool. My question is, are the 307 and 327 crank's exactly the same for balancing? I have the 327 block with large journal crank main bore's and a 307 crank with the same journal size. So fitting is easy. My problem, a**** other's, is a 3.875 dia piston should weigh much less than a 4.001 piston. Am I corrrect? Will this imbalance matter in a lower rpm motor? Or should I just shut up and have it all balanced?
The Jalopy Journal
