351M torque/hp/mpg

[thtniggey]

Hi im wondering if anyone would be able to tell me how much torque and horsepower i can expect out of my 351M with a four barrel weind intake and a 600cfm carb the truck has an auto trans thanks!!! Also if anyone knows about how much mpg can i expect?!?!

 

[DNFXDLI]

I think the factory number was around 160HP...you might pickup 20-30 hp with that...more if you put headers on and dual exhaust.
Mileage is going to depend on your right foot...I've seen people report between 8 to 15 or more depending on the truck.

 

[5.0Flareside]

maybe 200 tops at the crank.. and thats with a super duper weightless oil change and the perfect tailwind..

nah just kidding but 200 tops..

so looking at 160ish wheels if 20% loss through powertrain.

really need to do a cam and straight up timing set.. will work WONDERS...

 

[LEB Ben]

Agreed with all assessments, sub-200hp at the crank. As Chris said, straight up timing and torquey little cam can do wonders. As far as mpg's depends on tire size, 4x or 2x, gear ratio, etc. I've seen as good as 14mpg's (out of my Bronco) and as bad as 4mpg's.

 

[Mil1ion]

The 400 was 160 HP in 1978

The 351M was around 135 HP and 245 ft lbs of torque at 2200 rpm

All the 4 bbl will do with the secondaries actuated is shoot more gasoline and be wasted in the engine

The 351m in stock form is a dog and was meant to run with a 2bbl

In my world TORQUE is more important than HP

 

[thtniggey]

Thanks for all the help!!!!

 

[Beach66Bum]

The 400 was 160 HP in 1978

The 351M was around 135 HP and 245 ft lbs of torque at 2200 rpm

All the 4 bbl will do with the secondaries actuated is shoot more gasoline and be wasted in the engine

The 351m in stock form is a dog and was meant to run with a 2bbl

In my world TORQUE is more important than HP

 

[Alvin in AZ]

...straight up timing and torquey little cam can do wonders.
As far as mpg's...

x2

And those'll kick up the power and the gas mileage both at the same time!
No kidding.

BTDT

Alvin in AZ

 

[Lost]

My 79 F150 4x4 short bed 4:10 rears .I cleaned up heads header with duals preform intake and cam to match . I could do a u turn just mashing the gas . But I played with jets for different seasons . And only got 12MPG

Its a good motor if the work is done. But stock form sucked .

I miss the beast . Motor is still in a 69 Stang drag car .

 

[Baitshop]

Engines are glorified air pumps. 350 cubic inches is 350 cubic inches. If you take the time to correct some of the factory design limitations, your 351m will perform much like any other well tuned engine of that size. As has been said, put a good straight up timing set in it, a free flowing exhaust and an eddy performer 400 intake, maybe just a little cam, and it will probably surprise you. As with any engine, it's the combination that matters. The 351m/400 are not inherently bad motors.

Jared