351M ?
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- 1971fordcustom
- Blue Oval Fan
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- Location: Mountain View Arkansas
351M ?
does any one know how much HP a 351M Ford engine has? all I know it came out in the
smog wars when the US GOV was on automakers butt. My new 1971 Ford F-350 has that engine.
smog wars when the US GOV was on automakers butt. My new 1971 Ford F-350 has that engine.
http://s205.photobucket.com/albums/bb31 ... d%20F-100/
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck
- ToughOldFord
- 100% FORDified!
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- Location: Communist California, USA
Re: 351M ?
I'm no help here, but that's a damn good question. All my Ford books that list HP for various engines ALL say N/A under the 351M and 400 engine. I've never found an answer.
- sideoilerfe
- Blue Oval Fanatic
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Re: 351M ?
The 351M wasn't made until 1975 so someone swapped it in. Those engines are crap. The 400 is ok if you want to spend a lot of money on it you can make them pull pretty good. If you've got a 1971 then I'd find an FE to bolt in. 

Side oiler FE, see if you can catch me!!!
1970 F250 4x4 390/4spd
1968 F250 4X2 360/C6/No Rust!
1970 F250 4x4 390/4spd
1968 F250 4X2 360/C6/No Rust!
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Re: 351M ?
429/460 has the same bolt pattern and would make a better swap.
- ak-1970-360
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Re: 351M ?
I have a book titled The Ford Chronicle, I cannot remember who wrote it and since im sitting on the couch with a broken leg i really cant go find it. If i remember correctly it says that the 1978 351M was rated at 158bhp, however i do not understand what is meant by BHP but the whole book uses this rating and for some engines like the 428 Cobra Jet it says 335bhp which is the correct rating.
1970 F100 4x4, 360 FE, NP435, 9", factory 4.10, Homemade 4" lift, 35/12.5R15 MT Baja Claws- ultra budget 4x4 toy
2001 F250 4x4, Powerstroke diesel, auto, 140hp TS Performance chip, AFE cold air intake, hopefully adding soon- Jobe performance cold air intake, CFM+ intake manifold, 4" turbo back custom duals, stage 2 injectors- Daily Driver
Hot Rods have a Ford in front and a toolbox in the back, street rods have a chevy in front and a can of wax in the back- Mr. Offenhouser
07 Harley Davidson Nightster, 1200 with stage 1 programming, RSD intake, straight pipes, and Ape Hangers!
2001 F250 4x4, Powerstroke diesel, auto, 140hp TS Performance chip, AFE cold air intake, hopefully adding soon- Jobe performance cold air intake, CFM+ intake manifold, 4" turbo back custom duals, stage 2 injectors- Daily Driver
Hot Rods have a Ford in front and a toolbox in the back, street rods have a chevy in front and a can of wax in the back- Mr. Offenhouser
07 Harley Davidson Nightster, 1200 with stage 1 programming, RSD intake, straight pipes, and Ape Hangers!
- papabug71
- 100% FORDified!
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- Location: McAlester, Oklahoma
Re: 351M ?
BHP is "Brake" horse power. I think it is basic HP, with no drivline or accessory losses.
VIA WIKIPEDIA :
Brake horsepower is the measure of an engine's horsepower without the loss in power caused by the gearbox, alternator, differential, water pump, and other auxiliary components such as power steering pump, muffled exhaust system, etc. Brake refers to a device which was used to load an engine and hold it at a desired RPM. During testing, the output torque and rotational speed were measured to determine the brake horsepower. Horsepower was originally measured and calculated by use of the indicator (a James Watt invention of the late 18th century), and later by means of a De Prony brake connected to the engine's output shaft. More recently, an engine dynamometer is used instead of a De Prony brake. The output delivered to the driving wheels is less than that obtainable at the engine's crankshaft.
VIA WIKIPEDIA :
Brake horsepower is the measure of an engine's horsepower without the loss in power caused by the gearbox, alternator, differential, water pump, and other auxiliary components such as power steering pump, muffled exhaust system, etc. Brake refers to a device which was used to load an engine and hold it at a desired RPM. During testing, the output torque and rotational speed were measured to determine the brake horsepower. Horsepower was originally measured and calculated by use of the indicator (a James Watt invention of the late 18th century), and later by means of a De Prony brake connected to the engine's output shaft. More recently, an engine dynamometer is used instead of a De Prony brake. The output delivered to the driving wheels is less than that obtainable at the engine's crankshaft.

Matt
1971 F-100 Sport Custom - My grandpaws truck
Been in the family since 10/3/'71 (Brand spankin' new)
Mine since 5/7/'94
302 / 3 speed / 3:25's
--Currently undergoing full frame off resto/mod--
- 1971fordcustom
- Blue Oval Fan
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- Joined: Wed Feb 28, 2007 3:12 am
- Location: Mountain View Arkansas
Re: 351M ?
I know it got put in the truck! I've been after this truck for the past year! LOLsideoilerfe wrote:The 351M wasn't made until 1975 so someone swapped it in. Those engines are crap. The 400 is ok if you want to spend a lot of money on it you can make them pull pretty good. If you've got a 1971 then I'd find an FE to bolt in.
It did have a 360 but it thrue a rod! so the guy had one of his other engines put in it.
I dont wanna change any thing I Just wanna know HP. The engine runs great! Brand new 4BB Carb new Distributor, New Electronic Ignition,
http://s205.photobucket.com/albums/bb31 ... d%20F-100/
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck
- 1971fordcustom
- Blue Oval Fan
- Posts: 501
- Joined: Wed Feb 28, 2007 3:12 am
- Location: Mountain View Arkansas
Re: 351M ?
papabug71 wrote:BHP is "Brake" horse power. I think it is basic HP, with no drivline or accessory losses.
VIA WIKIPEDIA :
Brake horsepower is the measure of an engine's horsepower without the loss in power caused by the gearbox, alternator, differential, water pump, and other auxiliary components such as power steering pump, muffled exhaust system, etc. Brake refers to a device which was used to load an engine and hold it at a desired RPM. During testing, the output torque and rotational speed were measured to determine the brake horsepower. Horsepower was originally measured and calculated by use of the indicator (a James Watt invention of the late 18th century), and later by means of a De Prony brake connected to the engine's output shaft. More recently, an engine dynamometer is used instead of a De Prony brake. The output delivered to the driving wheels is less than that obtainable at the engine's crankshaft.

http://s205.photobucket.com/albums/bb31 ... d%20F-100/
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck
- papabug71
- 100% FORDified!
- Posts: 2002
- Joined: Mon Oct 13, 2008 11:31 pm
- Location: McAlester, Oklahoma
Re: 351M ?
I would guesstimate 150-160 HP at the crank. They were super-smogger motors, so dont expect alot of HP from it without some serious mods/cash. They are just like any other ford V8. They respond well to basic mods, intake, exhaust, mild RV cam, good ignition, etc. A new timing set will help it out as well. The factory timing set was retarded 8*. (I think).

Matt
1971 F-100 Sport Custom - My grandpaws truck
Been in the family since 10/3/'71 (Brand spankin' new)
Mine since 5/7/'94
302 / 3 speed / 3:25's
--Currently undergoing full frame off resto/mod--
- papabug71
- 100% FORDified!
- Posts: 2002
- Joined: Mon Oct 13, 2008 11:31 pm
- Location: McAlester, Oklahoma
Re: 351M ?
A group of the full size Bronco guys here in town have done some builds on the 351M & 400's. They seem to be just fine for a low geared 4x4, & they say most of the time people will dang near give them away.
After talking with the above mentioned guys, I have a new outlook on the 335 series motors.
After talking with the above mentioned guys, I have a new outlook on the 335 series motors.

Matt
1971 F-100 Sport Custom - My grandpaws truck
Been in the family since 10/3/'71 (Brand spankin' new)
Mine since 5/7/'94
302 / 3 speed / 3:25's
--Currently undergoing full frame off resto/mod--
- 1971fordcustom
- Blue Oval Fan
- Posts: 501
- Joined: Wed Feb 28, 2007 3:12 am
- Location: Mountain View Arkansas
Re: 351M ?
See my DRW Flatbed is a LowGear n its a hualin Truck so low end torque is good for me
http://s205.photobucket.com/albums/bb31 ... d%20F-100/
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck
1971 F-100 Explorer Special custom
1971 F-350 Flatbed
1966 Ford Galaxie!
1966 Ford F-250 4x4
1960 Ford F-750 FireTruck
1960 Gmc 6000 FireTruck
1962 IH R-185 Firetruck
1959 Ford Custom 300
1940 Ford Truck