Max RPM for 350 [Archive] - Chevelle Tech

: Max RPM for 350


Hunter
Aug 31st, 99, 6:24 AM
Does any one know what the max RPM would be for a stock rebuilt 69 350? It was out of a 69 Malibu 350/250 2bbl. It now has a mild cam, 4bbl, headers etc.
Thanks

Bob Bryan
Aug 31st, 99, 6:34 AM
Most any small block that is in good shape can wind up to 6500 rpm. The early small journal 327's had rpms that high with their two bolt main blocks and solid lifter cams. The real question is how high you need to spin your motor with it's mild cam and heads. It's hard to say what your red-line should be not knowing the profile of your cam; but around 5800 or less should be all you need to turn it. I have seen over 7000 rpm on my motor before (missed shift!).

DZAUTO
Aug 31st, 99, 3:54 PM
The NASCAR 350s routinely turn 8500+. And I realize that they are built for this kind of rpm. But my point here is that a SB Chevy can turn this kind of rpm and stay together-----------for extended periods.
Also, the early FACTORY Fuel Injected 283s in Corvettes were very capable of 7500-8000rpm. In the old days, some guys drove their cars to the track, spent a day of racing, and drove the car back home. And the early 302 Z-28s would wind to the moon.

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Tom Parsons

Fine69
Aug 31st, 99, 4:13 PM
Look on the cam card you got with the cam. It will show min rpm(point of lugging if under load), max rpm(where max hp is) and valve float along with lift and duration etc. or contact the manf. for specs. My card shows 2500 min, 5800 max and 6500 valve float. Someone set me straight if I didn't describe this correctly!

Dennis

67RAT
Aug 31st, 99, 4:19 PM
had a 350,2 bolt main,flat tops,2.02 double bumps,480,288 cam,team-g holley 650 dp,mallory unilite,headers,shifted at 7200 rpm,stopped makin power.67rat member #199

[This message has been edited by 67RAT (edited 08-31-99).]

L6571SS
Aug 31st, 99, 5:08 PM
I'll shift my 355 at 6000-6200 or so. Its just a little 2 bolt they'll handel it if you build them to do it. I'm sure more could be got but its only a matter of if you can afford to break it. A guy I know has a 302 for sand racing says he shifts at 9800.

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JT
71 SS Vortec 355
www.angelfire.com/co/KellyMotorsports (http://www.angelfire.com/co/KellyMotorsports)

David Nafarrete
Sep 1st, 99, 12:00 AM
Well one way to check is to nail the gas and hold it in gear until it lays down. You can probably rev to 6500 but it might not be making good power that high. Might run out of steam at 5500. I think cam specs are a good guide but they are not specific to the rest of the combo. You just have to see where it makes power. Get some strip time or a G-Tech if possible, that will help if you have numbers to back up the changes you make in shift rpm

Harley
Sep 1st, 99, 2:17 AM
Till it runs out of power, throws a rod or floats the valves. The cam card is a good fairly safe starting point though.

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Harley
69 461 El Camino Nitrous Model
69 Chevelle coupe
71 SS Camaro
75 L-82 Corvette
71 Gremlin X
Kerrville,Tx.

Bob Bryan
Sep 1st, 99, 3:42 AM
Just another note on this subject: It's not high horsepower than blows up engines it's high rpm.

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Bob (Creedmoor,N.C.)
65 Vette B&M Blown, Richmond 5-speed
68 Malibu B&M Blown, Turbo 350 10" converter

David Nafarrete
Sep 1st, 99, 12:58 PM
I think Hunter is confused from all of us. He said he had a 350 with a mild cam, not a NASCAR SB2. And not a circle track motor.

The reason I said what I said before is because that I know your motor isn't a race motor. Chances are you wont make much power above 6500. I never said spin it to 8 grand. That is unreasonable. And a fairly well put together small block should hold together to 6000 (unless you got some truck motor that revs to 4) but I doubt you will find much usuable power any higher than 6000.

I shifted my 327. mild cam, dual plane, 4bbl, headers etc etc. at 5800, I did the method I mentioned above when I first got the car, then when I had it dynoed that is where the dyno showed it I should shift it. Worked for me.

[This message has been edited by David Nafarrete (edited 09-01-99).]

mike reeh
Sep 1st, 99, 9:05 PM
I wouldnt go above 5500 or even 5200 or so unless you built the motor and are DAMN sure it can hold up.. Even with a 327 which by design tend to make power at higher rpm than longer stroked motors like 350, i get scared anywhere over 5000 rpm under load... in neutral i'll open it up to 6000 or so on occasion... but even then Im praying on the inside (but smiling on the outside)



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Mike Reeh
Gold #34
San Diego, CA