I have heard conflicting reports and nned to hear the straight skinny. Which year(s) 283 blocks are the sought-after ones to bore out to 4"? r
Most everyone says the 62 to 64 283's with the casting number 3789817 ... Mortec lists them as the same engine as a 327 ... because the block is supposed to be the same casting ... but the 283 ones were just not bored the full 4 inches that the 327 ones were.
Dont know but you can visually check for core shift by looking at the front of the block and seeing how concentric the metal around the front cam journal is. A good block has equal material all the way around it. If I had to guess Id say a HD truck block
I've been told (as recently as this weekend by a guy with a vintage SCCA corvette that runs a 283) that it's the early '60s truck blocks. Pick-ups, big trucks, makes no difference, just truck blocks. Mortec lists my original '62 Suburban block as "'57-'66 283". It's the original block. -Brad
I run a '57 283, bored .060 to become a 292, block in my roadster. That was good advice to check the front cam boss for core shift, but since '57 we've bored first year 283s .125 to make 301s with no problems. Unlike the newer GM castings the early blocks had thicker cylinder walls and my 292 runs exactly 100 degrees above ambient temp with a 160 degree thermostat. Have your machine shop check the block before boring. My block is a GM part #3731548, The FOGGER
I went into the machine shop asking how much can we bore it? and the guy just said - lets see how much it needs. It won't mean that much difference in the power output - .030 .040 or .060
I haven't had the mchine shop check it yet because I have a friend that has a '59 block and I have a '65 block. He'll trade me straight up if his block will go 4" and mine won't. Just trying to get the low down before I take a block to the machine shop. r
None of them! If you don't already have the pistons just get a set of 4.030 for the 3" stroke and use a 327 small main block. If you must use a 283 block get one with HB cast in the front next to the power steering mounts. Casting #944>>>>.
I never have understood why a guy wants to put a ton of dough in a 283 4" bore block. Once again if you don't have a set of free pistons that measure 4.00 bore and 3" stroke that means you have to buy a set of pistons. Just get .030 over and use the 327 block. But if you think that some 283's were made out small bore 327's in the 817 casting #s. it's simple to check. Just take the freeze plug on the sides out of the block. The 2 behind the motor mount pads. Measure the distance between the cylinders. Compare blocks as this is a simple task and can be preformed with a feeler gauge set. Naturally the sallest measurement will yield the thickest cylinders>>>>.
Probably cause it's lots easier to find 283 blocks than small journal 327 blocks. Even if you found a small journal 327 you'd probably have to have machine work done and need new pistons anyway. I have two 283 blocks in my dad's barn if you want another one Robin. Actually they have heads and intakes on them and are I think 63 and 64 blocks. I was building a 283 but stumbled onto two small journal 327's at a local machine shop. Sold one and kept one. Sold the 283 to Raven61. Tim
Let me get this straight. It's easier to find 283's so you stumbled onto 2- 327's bailed on the 283 build and sold the 283 to Raven61. So you helped him out with the demize of the 283 verses the 327 block question. I don't give a shit what block is used. Check the wall thickness like I said and use the thickest one. I promise you a 327 block bored to 4.030 won't give near the problems than a 283 4" bore at .125 over will cause. You want the thickest cylinder walls in what ever you build>>>>.
3789817....283...62-64...2 3789817....327...62-67...2 The above was cut and pasted directly from the Mortec site ... go here to see for your self. http://www.mortec.com/castnum.htm Now if the same year and same number casting for the 283 and the 327 does not make them the same block ... I do agree about not boring a 283 anymore than you have to. When I had my last 283 bored ( about 2003 ) ... I did bore it .060 instead of the .030 that would have cleaned it up ... but I had a NEW set of sixty over pistons.
Well, I checked the block casting. 3849852: 57-66 HB. I guess, that I won't hve to find another block. Now I just need to get it to the machine shop. r
You are pretty close. I got the 283 for free and sold it to Robin after finding 2 small journal 327 blocks hot tanked and checked for cracks at the machine shop for $150.00. I had planned on building the 283 but had not done any machine shop work on it. As I remember I sold the 283 to Raven61 for about what it cost me to get two already machined small journal 327 blocks. Then I sold the extra 327 block for $200.00. Just so you know. Demise of the 283 I don't know. So what if he bores it out? Will it crack? Who know's. Sounds like it's been done quite a lot. The point you brought up was why people put money into a 283 vs. a 327. Go out this week and start asking around for both and report back to me with what you find and how much you have to pay for either engine. I don't car what block is used either I was just pointing out why I felt people used 283's vs. 327. Let us know how many small journal 327's you come up with in decent shape to build this week.
That's the same one I've got from my '62 Suburban. I'm planning on keeping it for a "Some Day" drag engine, but I don't see the need to bore it to 4 inches. That's what 350 blocks are for. -Brad
It seems like there a lot of opinions here. In 62 there wasn't much to choose from in the small block lineup 265 283 327 were the production engines to date. 327 was only in a new car so that made it kind pricey.A .125 over 283 was the shit everyone was building them. That's why all the piston sets from that time frame were std. bore 4" 3" stroke. Hardly nobody would take a 327 apart to put a 3" stoke crank in it.A lot of people built the 4"X3" stuff but ask them how many blocks they broke and the heating problems that they had.Ran like hell but not ness. a long lived engine. If the 817 block was both a 283 and a 327 thats good.I'm only trying to give some advice so a guy doesn't piss away money on shit that won't last. I've seen person after person on this board that talk about how tight money is. My last bit of advice on this is take the soft plugs behind the motor mounts out. Now take a measurment across the top of the block between #1 cylinder and #3 cylinder. Record this measurement. Now measure between the water jacket through the soft plug hole. Subtract this measurement from the first measurement. Take that number and divide by 2 and that will be the cylinder thickness. Just for shits and grins I measured a customers block and the nums went like this. 1st-m=.533,2nd-m=.180 subtracted = 352 divided by 2=.176. Thats the thickness of the cylinder wall .176. Now take .125 out of the bore. This will be .0625 off each wall. That leaves a cylinder wall .113. You decide if you think a .113 thick cylinder wall is enough for a hot rod cylinder.And this is if the core shift hasn't made the wall thinner in some spots. You guys that want to piss and rant about this thats ok. Like I have said before "This is only my opinion and you don't have to do as I say or as I do>>>>.
Well, that pretty much says it but nobody mentioned sonic testing did they? I'm not a chevy guy but I see the reason to build a 301, I do remember that half of them were biolers and most didn't live but I also remember thrashing the living crap out of a 61 Vette for years straight. If you want to apply the "we have better stuff now" addage then why run bias ply tires or straight axles? Also what I remember about the 283 blocks it seems the earlier ones actually had better success rates as 301s. I never saw a 62, 63 or 64 301 that didn't boil or die quickly and I never say a 65 or 66 even attempted.
The only reason I never mentioned the sonic testing it's a bit pricey and the other is measuring method we used back in the day when this was a popular combo.Cheap and simple. One thing certain the 301 combo, and it's funny you call it that because back in the day that's what they were called,would turn rpms like nothing else. Like Ralph Cramden said TO THE MOON ALICE>>>>.
My Dad ran modified back in the 60's and used this combo. He always told me it was safe to bore any block 61 and newer, and he bored a bunch of them. Myself I like more stroke. The 3" stroke liked rpm's, but in a street car who wants that. It's hard to build compression with the small cube engines, and it's really easy to overcam them. Jeff
Well, there's just something about an engine that can spin 10 grand. Back in the day, where I lived, most 327s were pretty new, 250 or 300 horse and untouched. A 301 was almost always a built motor and would hold their own pretty good on Saturday night before the muscle cars came along. I saw one ever at Ennis last year running deep into the 12s in a 56.
The older articles (from mid to late '60s magazines) called for use of a '58-'62 block for large boring.
OK...'58 start to get good rear seal and semi full flow filter, I guess... One odd datum point: Grumpy Jenkins, in his first book on small blocks, written in low buck--junkyard days of racing. He opines that at 4X3 383 makes more powre than a 4X3 Z28 based on late 350/327 blocks because cylinders are round and expand more evenly...later blocks have flattened cylinder walls.
My experience with the 283 bored out to 301 is with the early blocks (something about being an old fart). After having experience with about 6-8 of them I never had any cylinder cracking problems with an early block after going 4.0 on the bore. There must have been a couple of dozen of those combinations build around here and the only clylinder problem was with a couple that came apart at 7,000+ due to bad rod bolts (a common problem with early small blocks as rod bolt tecnology hadn't caught up with load requirements imposed with high RPM) rendering one or two cylinders an easy water drain route. I've got a unassembled 301 thats been done using a '64 283 block so when I get it together we'll test the late block theory. I'm going to put together a '32 5w using all of the "junk" '32 parts I've got laying around and this 301 hand grenade will be the perfect finishing touch. Film at 11:00 Frank
I'll try to check. It dates to the days before Bowtie blocks and special heads, and is largely about harvesting the best stuff from the junkyard. Jenkins even looks grubby and half-crazed on the cover... His later more common book starts much higher on the food chain.
My brother bored 238 to 301 10 years ago, it run well, it was a twin turbo on gas (prophane), the motor was a Canadian block dated 64.
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