351W question

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Aug 8, 2010 | 09:03 PM

drunkdave

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351W question

I recently had 4.56's swapped in to my 89 bronco. The question I have is how how many RPM'S should I be able to safely turn at highway speeds.

Aug 8, 2010 | 09:47 PM

BaronVonAutomatc

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From: Earth

That would depend on the shape of your engine and what you consider highway speeds. Here in Texas anything less than 80 mph will get you run over, which works out to ~3,500 rpm for your combo. At 70 ~3,000 rpm. Should be no worries, assuming your engine is tight.

Aug 8, 2010 | 10:05 PM

drunkdave

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well, I thought it was in my signature, but it has a c6 in it. So i'm turning about 3000 @ 60 mph, and thats all the faster i will go then.

Aug 9, 2010 | 07:30 AM

andyman7931

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From: Western NC

I spin my 351 up to about 3400 rpm highway driving on a weekly basis. I don't like it, but when the speed limit is 70 and I want to do 75 I don't have many options.

Aug 9, 2010 | 08:48 AM

Encho

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From: Caracas, Venezuela

Without and OD you'll make that engine scream at the highway...

Aug 9, 2010 | 10:22 AM

Conanski

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From: Ottawa, Ontario

Yes.. get yourself an OD transmission, an AOD would swap in pretty easily and drastically reduce highway rpms(2000rpm at 70mph), a 5-speed manual would bring it down to about 2500rpm at the same speed.