The 400 is a good engine.
The 351M/400 use the same block. Basically the same engine except the 400 has a longer stroke, and makes more low end torque. Neither one are very rev happy, both were originally designed for B-I-G cars and trucks, so low end torque and lots of it was the goal.
If you were building a pulling truck, i would say go for it, but in a race application where you need revvs, a Windsor based engine would be better.
I have a 400 in my 78 1 ton, with a RV cam, headers, Edelbrock Torquer intake and 650 Edelbrock carb, T18 4sp and 4.30 gears it scoots right along untill about 70MPH. Like i said before, TONS of torque, not much horsepower.
Have you ever riddin in a F series with the 300 Inline 6? Thats basically what a 400 will be like, they have the same cam profile, same bore and stroke, the 400 obviously is more powerful because of its extra 2 cylinders, but like a 300, they have all kinds of low end (below 3500rpm) but fall on there face after that.
There is also little to NO aftermarket support for them.
But it would be Uber cool to see what one would do in a BII. Just build it to be a 400, not a 351M. Like i said they use the same block, just diffrent crank and rods. So use the 400 rods and crank.
later,
Dustin
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ok guys here's the deal. i have an 89 B2 2WD sittin in my yard that i cant get legal. (paperwork issues....dont ask) anyway, ive been thinkin about making it into a race truck, but not sure what engine to stick in it. iv built a couple of mud trucks in the past and have yet to do a race truck. anyway i came across a 351m/400 block in great shape for $25. couldnt pass it up. i know alot of ppl think they are only good for boat anchors but i want challenge. any advice/tips would be greatly appreciated. thanks
