Featured Technical Early 283 Question

Hey guys, hoping someone can give me some concrete information on 57 283’s

I have read that early 283’s where actually 265’s punched out and had overheating issues.

I'm wanting to find a 57 283 to build for my 34 but I want to avoid the ones that were punched out 265’s.

does anyone know if there’s truth to this?

or if there is truth to it how to tell?

I was looking at a Mortec book and the 265’s and 283’s are both the same casting number in 1957 (3731548)

anyone have some insight on this?

 

Must be a reason it has to be a 1957.
Chevrolet made 1.5 million cars in '57.
I don't have a breakdown on how many were V8's but if overheating was a big issue there would have been more reporting of it back then than I have read.

 

The block casting was not used in 56, when they only made 265s, so it seems to me that the casting you want was designed to be a 283, and was also used for the 265.

What is your alternative? If you want a 57 283, you get a 548 block, and you make sure the cooling system can deal with however little heat the engine makes. Compared to any other engine you'd put in there, the 283 is probably the coolest running candidate there is?

 

Pop bought a brand new ‘57 with a 283 and kept it until ‘64. Had to replace a fuel pump, but other than it had all it’s oem parts when traded ( only a little more than 50k on the odometer)!

 

The alternative is a 58-62 519 block. Which is fine if it comes to that. But you know we are nerds and I want a 283 without provisions for side mounts. ‍♂️

all the same that’s not really the point of this post.

the point is to see if anyone has any specific information around the 265/283 shared block situation.

like I said, I’ve seen mention of it but nothing that explains why or specifically what the issue was.

 

There is no problem, find a 57 block and use it. Overheating problems are seldom because of a .030" overbore on early casting blocks. Late model thin wall castings maybe.

Pat

 

The only 283 of any year that I remember having heating issues because of the cylinder bore were some that were bored over .060 over. Going out to 4 inches to make a "301" out of it ran the risk of overheating in street driven rigs.

Outside of Bubba factor I don't see the great and wonderful thing of having a no side mount block unless you are actually restoring a 57 to bone ass stock to show in national shows where being exact means points on the judging sheet.

 

Completely agree but my guess is that is not the case here but who knows, many times people (me), trying to achieve difficult tasks for no reason.

 

Interesting discussions

Here:
https://www.google.com/search?q=195...msung-nf-rev1&sourceid=chrome-mobile&ie=UTF-8

 

There were 265s in '57, they were yellow instead of orange.

 

I found a "548" 283 block that magically sleeved itself down to 265 when I pulled the heads off.
I sold it for a premium to a restorer who wanted a standard bore 283 engine.

The only giveaway is the awful calf-shit yellow paint

 

I have owned 3 57 283s have not had a heating with any of them. The only heating problem was with the ones that were over bored.

 

Again as aforementioned some of us are nerds and get very specific about what we are into. Sure I could run a 72 350 block and no one’s going to notice. But I could also use nylocks and that’s not gonna happen either….

devils in the details.

 

Also this is the HAMB, not Facebook. I don’t feel like I should have to explain that here.

 

I have a bare '57 block. Not sure if it's a 265 or 283.

 

so you're dealing with over six decades of "old wives tales", and you're trying to figure out the exact origin of the tales, and how much fact is involved?

Good luck with that.

Build the engine, drive the car, have fun! don't worry about the old wives.

get out the tape measure, see if it's 3-3/4 or 3-7/8" across the top of the bores.

 

I recently restored an original 57 283, factory 270 hp engine that had been bored .125 in 1959 by the original owner. It had some scuffs in the walls and I was nervous about wall thickness problems so I had it sonic tested. Hell, it had as much or more wall thickness than most of the standard bore 350's out there! We honed it .008, had J.E. make us some pistons and we're all good.

 

The Alfred E. Neuman mindset.

 

Terrible pic, but I'd say 3-7/8". My calipers are at work.



I didn't burn an inch....

 

when you need to determine the amount of over bore, you have to start measuring at an inch line, instead of at Zero on the tape measure...then you can measure to within .01" accuracy, if you take your time.

Yup, looks like a 283, not a 265. Congrats.

 

One thing that isn’t commonly mentioned as a difference between ‘56 265 blocks and ‘57 283 blocks is the way they oil.

The ‘56 265 was the first to have the canister oil filter integral to the engine block, and the way it sent oil through the engine block was like the ‘55 block. ‘55 and ‘56 used a “pulsed” oiling system, and Chevy changed to a “full time” oiling system for the ‘57 283.

Most people know about the notch in the distributor and the rear journal of the camshaft for 265 ci engines, but there are differences in the way the block is machined for the rear cam bearing as well. The ‘56 block has two oil holes in the block at the rear cam bearing that must be aligned with holes in the bearing, or oil will not be sent up to the top end. The rear cam plug on a ‘56 block is also different than ‘57-up.

A ‘57 283 (*548 casting) oils pretty much just like any of the later model SBC blocks.

To answer your original question, the ‘56 265 block castings and the ‘57 283 block castings were not the same block. There are the oiling differences between the two, and cylinder wall thickness was most definitely not decreased with the larger bore of the 283. The cores for the blocks during the casting process had to have been changed when they cast the 283 blocks for ‘57.

However…as previously mentioned above, there was also a ‘57 265 block that was used in the lower trim level cars like 150 sedans. It was painted Chartreuse to identify it as the 265 ci version. I have one of these blocks in my shop, and I don’t remember there being any obvious differences between it and the *548 283 ci casting, other than the size of the bore. I should get it sonic tested to see if it actually does have extra thick cylinder walls.

 

I have a 55 265 block along with the single year only oil pan. Just not sure if it is worthy of a performance build. It may be a restoration piece.

 

67 year old untouched 283 in this one.
Stock radiator and cooling fan. Does not run hot.

 

Maybe he doesn't want side motor mounts

 

Two of my cars have '57 283 548 casting engines, my '32 original Ford Roadster and my '55 Delray. One is .060 over and the other is .080 over bored. Neither one runs hot, all it takes is a well designed cooling system. Efficient radiator, thermostat, water pump and shrouding. I didn't specifically want '57 engines, they were just available.

 

If I'm not mistaken the 57 265s just weren't bored as far. Suffix code will tell you for sure what it is

 

But will 57 265’s have starter bolt holes in the block like all 57 283’s do no matter the transmission?

 

I've been professionally machining and assembling performance engines for 50+years and I have seen some pretty strange stuff so I do tend to err on the side of caution. NOTE: maybe you missed the "sonic testing part"! However it was very common back in the late 50's and early 60's to poke these pre 62 283 blocks to 4" with no problems and run the total shit out of them! "What? me worry"? ah no!..... I'm more of the "trust but verify" type.

 

I went to school for industrial machining but my first machining job was at a hi-perf automotive machine shop and we had people come in with one, no money and two, no clue and when they brought in some mess of an engine the shop foreman would say "the guy wants us to do magic and make chicken salad out of chicken shit, never forgot that one.

 

Yup. Word has it, if it is a C, it is/was a 265