Sam Cunningham broke the records (and alot of hearts) with a .030 over 283, or 287 if you rpefer. He kicked the shit outa Joe Grekas with that motor in his little '61 corvette. And it was running a Rochester fuel injection on it to boot...
250? The one I think we talked about was a 239 (238 and change!), which involved a late 70s 267 block (3.50 bore) and a crank from a 262 Monza V8 engine (mid 70s only). That gives you a 3.1 inch stroke. Unless you mug DrJ and steal his truck, though...them old "oddball" 262s are few and far between! As I recall, they only came in 75-76 Monzas! Pistons would probably be a custom order, though...unless you wanted like a 6:1 compression ratio! Ha Ha!! Put that same 262 crank in a 305 block and I think you'd end up with a 272...but again, rare crank and custom pistons!!
I know this isn't real small, but imagine the rpms. 400 block .030 over 262 crank 3.10 stroke custom rod and pistons but the cubes would be 323 ish. with a 350 or 327 block .030 over it would be 10 cubes less. 3.75 bore and its 292 cubes.....This is fun! My favorite will always be the 377. 400 block 350 crank. Mmmmmm
Sorry, most the "RPM" comments are wrong. The shortest stroke is any 1955-* 265, 283, or 302, common as dirt, in fact the only stroke made 1955-61: 3.00" The difference in RPM between a 3.00" stroke and the "long" (327) stroke, based on mean piston speed, is 8.3%. If the engine could turn 9,000 RPM as a 302, it could turn 8,300 with the 327 crank (no, this isn't the only limit). Those speeds will also require quite a bit of speed equipment both to develop the power (rods, piston, cam, valve springs), and to avoid flying into several hundred hot flaming bits of junk. You don't have to "imagine the RPM", it's just math. The smallest engine using stock parts will be the 267 3.500" bore with any 3.00" stroke crank, or 231". The only reason any race engines were built using smaller cranks is to get more power per cubic inch, not more power. A 327 is not made more powerful by reducing it to a 302. Given a fixed budget, the largest motor is going to be faster every way, every time. Starting with a smaller motor means adding $$peed equipment. "RPM means 'ruins people's motors'", quoting Larry Widmer. Want to say you have the smallest Chevy motor? Build a 383, and lie.
I'm pretty much a Chebby guy but I don't imagine that the Chebby is any more legeond than Ford. The SBF isn't or hasn't been a real popular but I've driven the GM 302 and the Ford boss and I'm equally impressed by both. I'm right with you on the short stroke thing. I was raised on short strokes and high revs. Ther is nothing better than getting one out and lettin it sing. I have said in the past and will continue to say high rev cruising is a rush. As for the original question, back in the '70s, or maybe the early '80s there was a non-HAMB friendly chevy here in the metro that ran a destroked 283. Floating around town here (still) is a real popular pic of the car taken through the back glass, launching wheels up and you can clearly see the big tach on the dash hitting 11K. As they say " he was just a shittin' and a gittin'!!!"
377 - A 400 block with 4.125 bore and a 350 crank 3.48 stroke is an excellent reliable "destroker" that will run as many rpm's as your valvetrain will live through, very popular dirt track engine. it requires the use of spacer bearings to use stock parts. you could use a large journal 327 crank 3.25 stroke and the same spacer bearings. keeping the bore as large as possible will benefit you when building these combos to unshroud the valves, high rpm requires as much valve as you can get into it, once your bore drops below 4.00 on a SBC youre going to have trouble getting even a 2.02/1.6 valve in there. heres mortec.com website if you want to play with the combos, bore/stroke chart and crank journal sizing. You could run a pretty big balancing bill at the machine shop to make some of these combos work. there are always nascar cranks on EBAY with short strokes, many use 1.88 rod "honda" rod journals, the good part is these rods are readily available, high quality, and cheap from used nascar engines. as long as you can get a crank with a stock 350 main journal and a honda rod journal you can bolt together a pretty cheap long rod short stroke 350 block screamer. save your money for heads to feed it and a valvetrain to make it live.
Back in the 70s the small engines at the drags were for Pounds Per Inch Cars. A 10lb car with a 287 ci engine would weigh 2870 lbs while if it had a 383 ci she would be up to 3830 lbs. With less weight on the start line a good 287 will win not to mention the driveline parts that you would save. Bob
Bob said it. As far as "imagine the rpms" comment, we're just bench racing, everyone loves the sound a well built engine makes at full song. Is it just me, or when bench bs ing, seems the fastest way to ruin it is with a no fun technical cramp.
Are you talking using all eight cylinders? some of the land racing guys used Small Block Chevy's with 4 pistons and rods removed. Bob weights were put on the crank throws for balance and the engine was run as a V4. 138 cubes was possible. cheeper than cutting the block in half.
...and they made just a 'few' 4v 302 engines from 1983 to 1986, too! Really, there's nothing mystical about a 4" bore and a 3" stroke. It's a tried-and-true combo that works and has in everything from the "legendary" Chevy Z28 engines, to the various Ford 302s...all the way down to the lowly Pontiac version that they elected to call a 301 (the Fords are 301 or 4.9 litres also, but they've always called them 302 and 5.0 ) You sure don't see anyone ravign about the Pontiac 301! (Because it was a lightened up, cheap-to-build economy motor...further proving that the old 4x3 formula works for whatever you elect to do with it!) When Jack and I discussed the "239" Chevy motor, my thinking was to create a small displacement SBC in a famailiar-looking package with smog-era parts (cheap) to come up with a fuel saving mouse motor that would look 'right' in a street rod but save a few pennies at the pump. Don't need gobs of power to move a light little roadster around, so it was my notion that a tiny small block would be kinda cool.
Easy, I wasn't intending on steppin on your toes. I spend all day playing around with hotrods cause my life sucks, and some times I like to just play make believe and live in the land of what ifs... You are right on about the piston speed, but don't forget the reasoning behind less stroke allows less rod angle and therefore less side load on the piston, causing less friction, in effect allowing higher rpms. So that said, the potential is endless with bore and stroke combos as long as there is a length of arm/lever (stroke). No need to mention what would happen if there were no stroke length, it's obvious. Not practicle, but still fun to think about.
Could the 301 Pontiacs be awakened with different heads and cam and intake suggestions? Or are they so weak they would crack under pressure?
301 Pontiacs have one of the weakest cranks ever produced by General Motors.Junk from day one.Not that I dont like Pontiac engines,just not that one.
301 is a thinwall block and can't be bored; it's also a shorter deck than all the others so only the 301 intake will fit it. It's easier to wake one up by replacing it with any other Pontiac motor. You'd be better off with a '55 or '56 block and having the bottom end modified for a later crank, or whatever that formula is, to build a 300-incher. How bad are 301s, that's the only motor I ever managed to blow up, and I wasn't really trying to - it just started to hammer one morning and I decided to try to nurse it home, I made it about 7 miles and it threw two rods, broke one in three pieces and bounced the piston off the valves. Just a bone stock 2-bbl 301 in a '77 LeSabre. To replace it and get some money back out of the car, which otherwise wasn't in bad shape, I bought an even higher milage 301 off a kid who'd been driving to college from a lot further away than I had to, with it. Which was good except that with this one in the car, I could go about 10 miles before it overheated. I never bothered to try to diagnose why, I was so tired of it by then.
I wouldnt go below a 4" bore on a sbc, youl never get a decent valve size in it, if rpms are the goal you need to feed it.
Weak cranks, thinwall blocks, lighter rods, shorter deck height, yes. They also used garbage cylinder heads with only two intake ports per head! The intakes were flat, low and many were single plane! You can bolt other Pontiac heads onto a 301 block, but then you're at a loss for an intake manifold to fit, since the 301 intakes won't work with standard four port cylinder heads too well! Cams interchange from other Pontiac V8s, as do lifters and timing sets but pushrods are shorter. Putting a cam in a 301 won't get you too far, though...make any RPM with it and you'll need a broom and a mop! There was a 265 inch cousin to the 301 that was the same design, only smaller in displacement. Just as bad!
just a nit picky thing, 302 chevys came out in 67 (Z28-283 crank/327 block) fords 302 was in 68 (67 mudstangs had 289's) BUT wasn't the 302 a STROKED 289? btw, i seem to remember some MP fords screaming away too. i miss modified production... "super" classes suck...
Knock yourselves out guys! Even a built-in calculator to help you envision your creations! http://www.donsautopages.co.nz/enginespecs.htm
I'm not a "Ford vs. Chevy" guy, but I had a CARBURETED '83 Z28 way back around 1990. It had a L69 305 H.O. motor, a 5 speed, and 3.73 posi- all from the factory. I can't tell you how many '89-'91 5.0 Mustang GT's I smoked with that car. SURPRISE!! It was loads of fun. __________________
I can pull 7000+ rpm on 1.72 valve in my 283s. I used to let the clutch out at 7200 while runing the drags with 283s. Bob
I don't talk about it here, but I have a LS1 camaro. And the only way a 4.6 suprised me was when it was supercharged. But enough of this new talk.
Back some 44 years ago I built a 311 cu in sbc (4.060 327 block/283 crank) with Isky roller and twin 750 AFBs on a cross ram...absolutely kick ass! Maximum rpm was only 9800 though. I took it to the local A&W for root beer...silly me! Frank
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