351 rpm range

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Oct 13, 2006 | 06:52 AM

Minger

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351 rpm range

I am rebuilding my 1972 351W to put in a 54F100. (Had the crank ground, cylinders bored out 0.030",new internals, just keeping it stock.) What is the RPM range that a 2 bbl carberatued 351. What is a good high way cruising RPM.

Looking to match the engine to a C-4 auto tranny and am trying to decide what rear end ratio would be best. (no towing or drag racing for this rig. Just driving).

Oct 13, 2006 | 08:52 AM

Kemicalburns

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From: Bend,OR

i would suggest a 3.08 rear gear. keeping the rpms below 2500 while cruising is nice but dont go below 1700 because then you will turning to slow.

Oct 13, 2006 | 11:50 AM

Minger

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I was thinking low 3's. Will a 3.07 be too low for 1 and 2nd gear through town? Espicaiilly first gear. I don't wanna lug the engine pulling away from lights in town. As always, thanks

Oct 13, 2006 | 12:21 PM

bronco521

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From: right here in michigan

your tire size will have a bearing on this also.is this two wheel drive?i had a car with 27.5" tall tires and 3.42 gears and it was 2500-2700 in the 55-60 range.

Oct 13, 2006 | 03:15 PM

Kemicalburns

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From: Bend,OR

3.08 was standard in some broncos running the 300-6/C6 combo so if that setup worked for that heavy of a truck , i think it will work for you

Oct 13, 2006 | 04:38 PM

85e150

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Unless you already have the C4, consider an AOD. That way, you can run a little shorter gear and still cruise at low revs.

Here is a calculator link so you can figure your rpm/mph with various ratios and tire sizes.

http://www.novak-adapt.com/knowledge/gearing.htm

AOD links.

http://www.transmissioncenter.net/AOD.htm

http://www.becontrols.com/products/aodcat.htm

http://ckperformance.com/ford_aod.html

http://www.tciauto.com/Products/Ford/ford_aod.asp

Oct 13, 2006 | 05:08 PM

Minger

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Bingo,I already have a C-4. I like the idea of AOD but well,I have sunk enough money in this (some how it always takes more, huh?) and for as much as this truck will be on the road, I guess it would take lots of miles to pay for the AOD from the gas savings over the C4. But I'll check the links incase I stumble into an AOD. Thanks