RPMing a SBC engine.
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RPMing a SBC engine.
How high should a 3.53" b x 3.00" s = 234.88"cubic inch engine rpm if built to do so?? 8, 9, 10,000 rpm and higher?
I have read and heard about guys rpming the little 265's and 283's way up there so just am asking about one made from the 267" engine block is all.
pdq67
I have read and heard about guys rpming the little 265's and 283's way up there so just am asking about one made from the 267" engine block is all.
pdq67
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Re: RPMing a SBC engine.
With a stock block and valvetrain architecture?pdq67 wrote: ↑Sat Dec 09, 2017 5:12 pm How high should a 3.53" b x 3.00" s = 234.88"cubic inch engine rpm if built to do so?? 8, 9, 10,000 rpm and higher?
I have read and heard about guys rpming the little 265's and 283's way up there so just am asking about one made from the 267" engine block is all.
pdq67
-Bob
Re: RPMing a SBC engine.
Thats a question like, how long is a string?
Even if you gave all the specs of the engine it would still be a guess, although a more educated one.
Even if you gave all the specs of the engine it would still be a guess, although a more educated one.
Monty Frerichs
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Re: RPMing a SBC engine.
No way you could find heads suitable for the 3.5" bore.
So much to do, so little time...
Re: RPMing a SBC engine.
Early 90's I did a 267 for economy. Stock dualjet ported stock manifold, rv style cam, lt1 springs, ported 267 heads with exhausts opened for 1.5" exhaust valves, ported iron exhaust manifolds, 6500 rpm and was much better driver than stock. Guy loved it said he could get 22 mpg or better in a Monte Carlo about 1980 style. Thanks, Charlie
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Re: RPMing a SBC engine.
What was the B & S on that one Charlie, just curious thanks Mark H. Bore and stroke.
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Re: RPMing a SBC engine.
There is no advantage in the smaller bore, when it comes to RPM potential. 4.000" bore, 3.000" stroke (301/302) architecture will easily rev to 10,000 RPM with the right combination of components. Basically this means cam profile, valve springs, ignition and fuel delivery. Secondary elements would be intake manifold/intake port design and exhaust port/header design.
But to answer Paul's question, the "little" engine would probably turn 10K RPM as well, as long as small valve heads are utilized, so that the valve shrouding won't be a major stumbling block . . . . . . However a 4.185" bore, 3.000" (or less) stroke engine with the right components would be able to achieve similar RPM levels and produce a bunch more horsepower than the "little" engine concept.
But to answer Paul's question, the "little" engine would probably turn 10K RPM as well, as long as small valve heads are utilized, so that the valve shrouding won't be a major stumbling block . . . . . . However a 4.185" bore, 3.000" (or less) stroke engine with the right components would be able to achieve similar RPM levels and produce a bunch more horsepower than the "little" engine concept.
Bill
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Re: RPMing a SBC engine.
3.00" "(or LESS)" now we are talking Comp. Elim.-----Yeah baby get up there and sing---3 per cube + or - gives me chill bumps. Mark H.
Re: RPMing a SBC engine.
That one was .030 over 267. Tiny bore 3.48" stroke. I seem to recall the 267 being a "square " motor. I think I only ever built two of them. As long as the customer wasn't looking for any real power they were a nice little engine. Thanks, Charlieswampbuggy wrote: ↑Sat Dec 09, 2017 9:45 pm What was the B & S on that one Charlie, just curious thanks Mark H. Bore and stroke.
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Re: RPMing a SBC engine.
Not sure why anyone would waste one penny on one of those. I would try my HARDEST to talk someone out of one of those piles. THey are worthless heavy and gutless. Why not spend less on a 350. The mildest of 350's will still make WAY more power and get just as good if not better economy if that's the idea behind using one.Carnut1 wrote: ↑Sun Dec 10, 2017 3:43 amThat one was .030 over 267. Tiny bore 3.48" stroke. I seem to recall the 267 being a "square " motor. I think I only ever built two of them. As long as the customer wasn't looking for any real power they were a nice little engine. Thanks, Charlieswampbuggy wrote: ↑Sat Dec 09, 2017 9:45 pm What was the B & S on that one Charlie, just curious thanks Mark H. Bore and stroke.
Re: RPMing a SBC engine.
That is why I only built 2!Frankshaft wrote: ↑Sun Dec 10, 2017 12:12 pmNot sure why anyone would waste one penny on one of those. I would try my HARDEST to talk someone out of one of those piles. THey are worthless heavy and gutless. Why not spend less on a 350. The mildest of 350's will still make WAY more power and get just as good if not better economy if that's the idea behind using one.Carnut1 wrote: ↑Sun Dec 10, 2017 3:43 amThat one was .030 over 267. Tiny bore 3.48" stroke. I seem to recall the 267 being a "square " motor. I think I only ever built two of them. As long as the customer wasn't looking for any real power they were a nice little engine. Thanks, Charlieswampbuggy wrote: ↑Sat Dec 09, 2017 9:45 pm What was the B & S on that one Charlie, just curious thanks Mark H. Bore and stroke.
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Re: RPMing a SBC engine.
I had one I was going to use to replace the 250/6 in my 72 Nova. It never got built, but a friend had one in a 79 Malibu that lasted over 350,000 miles and still ran good when he sold the car. I still prefer the small V8 over a six, they vibrate less. If I want horsepower, I use a 400 block.
So much to do, so little time...
Re: RPMing a SBC engine.
I'm thinking to just rpm it whenever I need to get out of somebody's way here is all.pdq67 wrote: ↑Sat Dec 09, 2017 5:12 pm How high should a 3.53" b x 3.00" s = 234.88"cubic inch engine rpm if built to do so?? 8, 9, 10,000 rpm and higher?
I have read and heard about guys rpming the little 265's and 283's way up there so just am asking about one made from the 267" engine block is all.
pdq67
Drop it down into 2nd gear and put my foot in it and let her go to way up top. Get outta the way, then shift up to 3rd and continue down the road.
pdq67
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Re: RPMing a SBC engine.
With modern rods and pistons, the limiting factor will certainly be your valvetrain
Ti valves?
Shaft rockers?
Ti valves?
Shaft rockers?