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Discussion Starter #1
Hello!
I was wondering how far I can rew my engine....
It's a 302 from a '71 mustang, 2bbl.
It has been "rebuilt" by the previous owner, wich means he had it apart and put in new bearings and so on, no machining.
New cam ([email protected]) and the valvesprings are beefier.
Apart from that it's stock. (headers of course but they aren't interesting here...)

So...
How far will this go without beeing too dangerous?? 6000/5500/5000rpm ? I guess it will do more that 5k at least ??
Is it valve float or something else that will limit the "safe" rpm.
 

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Well, theoretically a 300 cubic inch motor will redline at 8000RPM, but if you take it to that, you better have another motor in the garage... I wouldn't take it past 6500RPM... 302's were made to rev, and people who know the engines have told me 8k, but like I said, I don't think 8k is too good. A stock 351 shouldn't really be reved past 5500. Also, you don't want to end up on the wrong side of the curve, you should find out when your engine starts and stops making power.
 

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Discussion Starter #3
Swift reply!!!

Thanks cmpcpro!

Ok, so 6000rpm shouldn't be a problem then, even for a stock 302? Without blueprinting and balancing?

Anyone who knows at what rpm the valvespring matching a 218degree cam will start to float?
Don't have the specs on the springs but it should be what's recomended for a cam like that...:rolleyes:
 

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Yup, stock or not, 302's were made to rev. Though Jim is right, your intake (Like mine) might not make power up to that far, like I said, you should find out what RPM's your motor makes power at.
 

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Unless you've done something with the breathing - inlet manifold carb and exhaust - you won't get much gain over 5,500. If it has an auto behind it probably not much over 5,000.

302's respond well to free flowing manifolds and head work. For drivability you don't need big ports just nice smooth ones matched to the manifolds - and to roller rockers / double valve springs and a bit of a cam and you will pull 6,500 easy with manual

If you have an injected 302 with aluminium heads, good balance, roller cam and headers you can pull 7,200 all day with little problem
 

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Discussion Starter #7
Right now I'm running the stock 2bbl manifold, portmatched heads with mildly ported exhaust and headers, and I guess I don't need to rev that high but it's nice to know that it woun't break if I do. :)

But for next year I'm planning on replacing the 2bbl with either a quad or fuel-injection, so then I migh have some use for those extra rpm's.

Thanks everyone!
 
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