I have a chance to pick up a 283. The guy says it has been bored and is using 350 pistons but still has the 283 crank. Not sure why anyone would do this. lol. My question is...what CID would this engine be??? I'd like to match a cam and intake but I'm not really sure where to start
301, but the 350 pistons wont work i think. You have to have .125 over 283 pistons or stock 302 chevy pistons
The 4 inch bore would make it a 302. I would be pretty su****ious of 350 pistons having the correct pin hight. I think you should look inside that thing and see what you bought.
Doubtful on the 350 pistons. .125 over would be pushing it. Street cam in the .425 lift range, dual plane intake (off idle to 5500 RPM) Find out its true displacement/machine work.
As said before 302. The reason that person may have said 350 is because the 302, 327 and 350 all have a 4" bore. But all the have a differant wristpin location on there piston to make up stroke differance.
Possible with 350 pistons if there are longer aftermarket rods. If so the engine would be quite good for higher rpm. Better rod angle ang lighter pistons.
In 1958 it was always called a 301 by the hotrodders. In 1968 Chevrolet rounded the decimal point up to become a 302. What you call it will be a product of your age. It's still the same thing. I call them 301s if that tells you anything. There was an altered that ran Capitol raceway in the 60s. It was a Singer (Google it) There was a funny looking door knocker on the grille shell. I asked what's up with that? It was stolen from a local apartment building. The first apartment on the third floor. Yep it was running a 301 For the Google impaired.
If it really has 350 pistons it will be a 301 with extremely low compression ratio (probably run on panther piss). You would need rods with a center to center length that are longer by the difference between the 283 and 350 pin height to make the deck height come out right. Frank
Could be a small journal 327 block with a 283 crank. I built a 302 last year and put it in my mid engine corvair. Only problem is there are currently no flat top pistons available for this combo. Ended up having to run racing gas.
Honestly? I think the seller is just spewing out numbers and parts that he/she has heard over the years figuring that 350 pistons must be hi po. The 283 has a 3" stroke and the 350 has a 3.480 stroke and they both use rods that are 5.700 long. The height from the center of the pin to the top of the piston (compression distance) is 1.780 on the 283 and 1.540 on the 350. To get the 350 piston to come up to the deck with a 283 crank you would need 6" rods which are a very common rod as far as length but since I have not been in the hunt to build the fastest SB Chevy I am unsure of the availability of 6" rods in the smaller 283 rod journal size. If indeed this engine was built with the correct parts to get everything to work the success rate of boring a 283 from the standard 3 7/8" to the 4" 350 bore size was not very good. This can perhaps be done today with a block filled with Hard Block or the equivalent but doing that would be suitable only for drag racing. I believe the seller is BS'ing due to having been told this by someone else, they are BS'ing to make a stock engine sound good or BS'ing to pick your pocket. And as far as a longer rod, they do reduce the rod angle so there is less side loading on the cylinder wall and the time that the piston is stopped at TDC and BDC (dwell time) is increased which gives additional cylinder filling on the intake stroke and more power on the power stroke.
No logical way of putting 350 pistons in a 283. Even with a 4" bore (which might or might not work) the piston pin height is wrong. Do you want to trust that he knows about the rest of the engine is, if he doesn't know this? Larry T
4 inch is possible on the early 283 block. 350 pistons are also possible with the right rods. Somebody would have had to know what they were doing to build it but it is possible. Anyone who has driven a 301 knows why they are built. They will wind forever. 8,000 rpm is no problem. We once ran a 351 Windsor with an offset ground [stroker] crank, 350 chevy pro stock pistons, narrowed 348 chevy rods and 2.02 chevy valves in the heads.
Also all (If my memory serves correct) 327's had the smaller rod journals like the 283 but with a 4" bore..so that could be one of those and if all's good with a 283 crank and 302 off the shelf pistons.
std 283 rod journal size is 2.000 very common rod combination is 2.0 crank 6.0 center dist .927 pin I think the 283 rod width is narrow compared to a later motor, easy to have narrowed. John
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