Thread: 283 with 327 crank

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Hi. Im going to purchase a torn down 283 sbc ('58-'61) thats been 0.060 overbored. It comes with a 327 crank and connecting rods, and also with 307 pistons (0.060 oversize). it also comes with the original 283 crank which i believe has been machined but im not sure what has been done to it.

My question is, can I use the 327 crank and rods with the 307 pistons? or even the 283 crank? I guess if i use the 283 crank i'll have to get new rods. I want the bigger stroke but I don't know if the 327 crank will fit the block, and if it does, and I use the 307 pistons, will there be an issue with the total height of the pistons?

Also, the heads are 283 powerpack heads, 64cc from what I could tell.

It seems like kind of a mess but Im getting it for pretty cheap so I'm not complaining. Any help is appreciated. Thanks,

A 283 and 307 both have the same bore. A 327 crank has the same stroke as a 307(so the piston deck height is fine). The problem is... the 327 crank. A 283 only came with a small main journal crank(2.30"), but 327's came with both a small main and large main(2.45") journal crank. If the journals measure 2.30" or near that(turned down) you will be fine. Still I would assemble the short block "dry" to make sure you have what is said to be. Hope this helps.

Before we go any further-we need to know the main bearing size of the 327.

I believe it's a small journal crank. its in the block right now. The guy I bought it from seemed to know what he was doing, but I'm not assuming anything haha. I haven't had a chance to check numbers or measure anything on the crank because the block is off the stand and the crank is inaccessible right now. but I'll make sure when I take a look at everything on the weekend. does the fact that it fits in the block mean it will work?

The piston pin heights are different as well i believe
Mark

Whats the number on the block, on the bellhousing behind the driverside cyinderhead? I think all connecting rod lengths were the same(5.7"), except for the 400(5.65)? Anybody know for sure?

The piston deck height should be okay. as far as I know chevy didn't really change the overall cylinder block height, they just changed the piston-to-crown length to accommodate longer stokes. so the 307 pistons with the small journal 327 crank and 327 connecting rods should be fine - because all connecting rods share the 5.7" length except the 400's. but i did notice that the 307 cranks had a larger rod-journal diameter, so 307 connecting rods would have to be used in that case (just in case anyone is wondering).

oh the block number is 3756519.

thanks guys

.I am new to this sight and new to this building rods. What are the benefits of mix matching parts , the crank and rod from the 307/327 to the 283 block ? Hopefully this isn't a dumb question

Im new to this too so don't worry. the 327 had a longer stroke that will essentially give you more power per stroke. But because the piston travels farther you need a piston with a shorter pin to crown height so the pistons don't come out of the top of the block ( 307's and 327's had the same stroke and essentially the same pin-crown height). The only reason the 283 block is used in this case is because the 283 from the late 50's - early 60's had thick cylinder walls that can be bored out to give you a greater diameter cylinder, again adding to your power. Increasing the 283's cylinders like this (0.060 over) gives you a displacement of about 302 or around there i think

build a factory spec 302 chevy, 11:1 cast pistons 64cc chamber camel humps, solid cam .485 or you could use the offroad cam .493 .512 instead of a dual plane pop a strip dominator intake on it with a 750-850 carb you will have 375+ horse, bone stock with a dual plane and a 780 they dynoed at 350-365

would I be able to make around 300 horses with this setup i have (I would hope so haha)? Im going to go with a bit more aggressive cam than stock obviously, and probably a 650cfm holley. Im just using it for street applications so Im not doing anything too extreme. What would be a decent cam setup for this, assuming hydraulic lifters?

I can tell you the way to build the 302, I did for a circle track car many years ago. Guess what the 327 block is a 4" bore same as a 283 bored .125. So why bore the block to death when you already have the block? Put the 283 crank and rods in the stock 327 block with 283 pistons .125 over. You have to have the 327 small journal crank block, because all 283's have the small journal crank. The pin height in the piston makes the difference, not the rod. Best motor I ever had and is still running 30 years later. Back then the 283 bored .125 over was common so pistons were everywhere, I read how GM made the original 302's and came up with this idea. I just bought a 67 El-Camino with a 283 and am looking for a small journal 327 block. Not so easy now, and the guy I sold the motor to said it will never be for sale again. So stock bore 327 block and 283 crank with 283 pistons bored .125 over. Has to be 283 or 302 pistons only.

You can use any of the 4 inch 350 blocks AND a set of spacer main bearings or a set of bearing spacers and early bearings---If you want something better--400 block, spacer bearings and 302 crank---one of the best outlaw dirt motors I ever built

+++ What Doc said, we did that years ago,the old 327 block and 283 crank(small journal) trick.Get some 11-1 or 12-1 302 pistons and 5.7 rods,a little methanol and 8000 rpm's here we come! Not a great deal of torque but the sound of that small block screaming like a banshee down the back chute at Williams Grove Speedway would make the short hairs stand up! At the time it was considered the poor mans stroker.Good luck!
OL'Bill