The 283 Chevy ('65 block)that I will be soon installing in my '63 Biscayne was rebuilt when I bought it. It is bored .60 (was sono checked. I have info), flat top pistons, mild cam, steel crank, and 305 heads. Has about 10 or 15 minutes run time on it. (I will be sure to break it in (cam etc) properly) I added an Elelbrock Performer intake, Edelbrock 550 cfm carb, and 2 1/2" Rams Horn exhaust. Will be running a Saginaw 4 speed trans with it that has a 3.50 first gear. Rear end is an open 3:36 out of a '57 Chevy with H70 14 Pro Track bias tires. (~27.5" tall) From reading a lot about this fairly common set up, I am wondering what "realistic" rpm's I should (could) be able to rev, especially in 1st and 2nd gear. Some say 7500, some say stay at 6500, some not over 6000, and so on. Anyone have any actual experience or good info for me? This is just going to be a street driver with a little attitude....I will not race or run it hard, just screw around with it on occasion, but don't want to ruin it either... Thanks for any comments... Cheers, Bob
chevy's 302 used the same stoke as the 283 if i remember correctly, and that motor was known to see 9 grand. At that point i would be more concerned about wether or not your valvetrain could keep up and would be worried about floating the valves and causing some degree of catastrophic engine failure.
If it's had the pistons changed and not balanced, I'd keep it under 6000. And that's probably close to the max that the valve train will take unless it's been upgraded. Larry T
That 302 mentioned above had much better rods and that is a biggie. Floating valves will act like a built-in rev limiter, once you get past that it is up to the connecting rod, then the pin. In your case the rod will last to above 6500, much above there and its' kinda iffy. But like Malpass said i'd worry about floating the valves first.
i'll also add that you would really have to be doggin the crap out of that motor to get it over 6500 in that set up. no real reason to push it that far.
You have a 63 biscayne with a 283, how fast do you think you're going to make it go by reving the piss out of it.
In the old days a lot of guys were pulling 10k outa stock class drag cars, running stock rods Ect, Same with the old 302's, which the only difference was they ran 'pink' rods that were shot peaned and mag'ed I'd say a fresh motor should be fine on a regular basis at 6k or 6,500 but it your choice above that
The Cam and valve springs will be the limiting factor. Your setup is similar to the setup my son had in his '66 Nova. Not a lot of bottom end and ran out of steam just below 6,000 rpms. The Mid range was great though! Valve float was a problem at 6,000 rpms. This was a fresh engine that was balanced and very well built, it had World Product 305 small chamber heads, a Comp 268 cam, flat top forged pistons about 9.5/1 compression, 600 cfm Edelbrock carb, the builder estimated about 300 horse! P.S. My son has a set of brand new bee hive valve springs that will raise the rpm level. PM me if you think you might be interested in them.
A lot depends on the valvetrain pieces and the breathing ability of the entire combination. If the intake, cylinder heads, exhaust system, pushrods, valve springs and camshaft have all been upgraded and are designed to push 7500 then you're fine doing that. However you have a street-oriented 283 in a heavy car with street gearing and stock exhaust manifolds (even if those are Corvette rams horns). A Performer intake is not a 7500-RPM intake, nor are rams horn manifolds. Combined with a 'mild' cam, your engine won't need to nor will it really want to turn over 6K.
If you re read my post, I was not asking about top speed, or reving the piss out of it. Just didn't want to hurt it in 1st or 2nd gear...and wanted clarification on rpm suggestions, which now I have, thanks to other answers. Simple question......dumb answer on your part.....
I agree 100% with draggin'GTO. I have basically the same combo (305 heads & mild cam) and it runs out of steam just after 6,000 rpm. It just stops breathing with the top end combination that I have. If you have a good balance job, the bottom end will not be the limiting factor.
Just to be wise ass Are you going to trust the 50 year old flywheel over 6000.?? I ran a pretty stock 283 back in the 60's when the parts were new and I was able to see 6800 with mechanical lifters, Duntov cam, powerpac heads , stock springs and pinned rocker studs, and a two barrel Rochester for P/S racing.
I wouldn't rev it over 6K and the valves will probably float before that anyway. When horsing around I would shift it at 5K Max in 1st and 2nd. That way if you miss a shift (and I bet you will) you'll have more time to get out of it before you do some damage. Remember that's a heavy car you're trying to move with that little motor.
In a nut shell this about covers it. As stated, to exceed this rpm range there will have to be substantial upgrades to the valve train and the rod bolts (which WILL be the cause of a catastrophic event) before any reliability will occur beyond that point. If it were mine I'd content myself with showing the occasional VW where it's at leaving a stoplight. A 283 in this heavy a car is a cruiser not a bruiser. Frank
You didn't build the motor. Keep it under 6k & it will be happy. I doub't it will see much use on street above 5500 anyway.
That aforementioned Z28 302 engine ran solid (mechanical lifters) and could rev as high as 6800 RPM without scattering. If my memory serves me right, those 302 heads also had 2 things going for them: a lotta compression & large, smooth flowing ports, which develop a hell of a lotta power real quick. The 302 was, arguably, one of the hottest SBC's ever produced. For MY money, I'd go with the 301 variant; a 283 bored out out 125 thousandths, 327 pistons, and 202 "double humper" heads. IN ANSWER TO YOUR ORIGINAL QUESTION: your engine should be capable of 6000 RPM's, given the way you've set it up. Good Luck!
Keep it safe and about 5500 rpm unless you know about the valvetrain maximum safe rpms.3.36 rear might be doggy in high gear in a big car.3.70's with a 3.11 first gear Saginaw and let the engine rev on the hiway.
I would make 5500 a rare event not a common one, that way you will be able to drive it and not repair it.
Bob: After you break it in and get used to it, you will discover that a shift point of 4000rpm or lower will be comfortable for you. At 4000, you will actually think it is twisting pretty hard. At 5000 rpm, you will pull back the throttle, as it will be screaming and your common sense will kick in. I had something similar and that was my experience. She goes, she goes. She blows, she blows. have fun, Bob
sounds like my guess......sure it may rev to 7500 , but will the valve springs last oh wait , that was my experience with a big cam 273....
If you want an accurate answer it's easy...rev it till it pukes parts out the side and next time keep it at 100rpm less
This is a great forum indeed! Thanks all for the info... Me thinks that when I feel 18 years old, (now 66) and need to hear some screaming, (Or want to show that 40hp VW who is boss ) I will probably limit my revs to ~4500-5000 rpms. Last thing my budget needs is a blown engine. Cheers, Bob
6000 will be nice and safe for a short stroke 283. I was shifting my 355 at 7000 with a somewhat stock bottom end and it never hickuped....ever. Biggest difference was I had good valve springs and solid lifters.
i like high rpm chevys. I have a 287 and 377 in my cars. You wont get anything past 6 if you have stock stuff valve train. Probably also damage the pistons in the long run. With a good cam with 240 duration or more you could probably get 65 or 7 but you will need a stud girdle and at the very least roller tip rockers from Comp cams with good springs. Theres no point in going past 55 if you dont have the cam and heads to take you there. I had a Ford 302 that hit 7000 all the time but I had Dart heads, pro magnums, stud girdle, titanium retainers, dual springs. I have spoken to those that ran low 10s with 301s back in the late 60s early 70s and they all say they popped rockers hitten 9 grand and even screwed up a few spring sets every time they raced. Some of them began using a very early shaft style rocker arm system and that was considered super stock stuff style one off sets.
gas pumper is right have you ever seen parts of a flywheel go through a dash and windshield and the rest cutting gas and brake lines use to happen often
I know how you feel Bob. I wanted an engine that would rev so high only dogs could hear it. Why? Just because I wanted one. You can build an engine to do almost whatever you want, but if you want high rpm's, you need a solid lifter camshaft, a hydraulic cam is only good for about 5500 or maybe 6000. I have a 289 that was built to rev with a solid flat tappet cam, and I balanced the rotating assembly and installed ARP rod bolts so the rods wont end up in my front fenders. I do need stiffer valve springs though, we had it on the engine dyno tonight and it runs out of spring at 7200, but up until then it's still building power. Basically what i'm saying is, it's perfectly safe to rev it up to what it's built for. JW
More (I hope valid) points: With a "mild" cam, you probably would be wasting anything over 6000, the HP curve will be lower than that. Agree with the valve train problem, but also, if you are running a stock distributor, you are going to get point float. We use to run a set of points that had a better rev limit, I think I remember they were BR8P part number, but damn if I can remember who made them. But in any case, that could pop up and be a problem too. Biggest factor to me is the first. What is the point of revving the enging higher if the power curve is dropping like a rock at the same time.
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