Hey everyone, my father and I recently acquired a nice roller 1977 F100 and we're going to throw and extra 351M we have around in it. This thread will be the buildup of this engine over time.

So far our parts list/plan is pretty extensive:

Stock reman 400 crank from rock auto

TMeyer .030 over pistons

Howards Big Daddy Rattler cam

Speedmaster79 aluminum assembled Cleveland heads

Edlebrock performer 400, plumbed for nitrous

Holley Sniper EFI and distributor

Stock connecting rods


Goal for the motor is to be a nice street/strip cruiser. Going to try to spin it to 6500-7000. Has anyone ever put together a similar build? If so, what are some things to look out for or anticipate down the road?

 

Dumping the cheap Chinese heads and the Edelbrock manifold is the first thing I would do. Get a good set of heads such as TFS or CHI ect (not Edelbrock). Go with a Weiand manifold and port match it to the heads. Also spinning a 400 with a 4" stroke at 6500rpm gives you the same piston speed as a 351W/351M with a 3.5" stroke spinning 7500rpm. That's a lot of stress on the rods and pistons. I see no need to turn a 400 over 6k, Tim M gets over 500hp from built 400's and I have never seen one turn more that 6k. If you do plan to spin it hard, 1- stud the mains 2- arp rod bolts the rods 3- polish and shot peen your rods and I would start thinking about more serious oil mods than just Tim's oil mods. Sure the pistons and rods feel the stress of the high rpm more do to piston speed, but the main bearing speed is identical because both the 351W 351M and 400 all have the same main bearing sizes, so no high rpm mods need to be made unless your spinning more than 6k in a 400 (in my opinion). Oiling mods include things such as the external oil line mod, bushing the lifter bores, running restricted pushrods, HV oil pump, standard oil pump with HP spring, etc. Finally I highly advise you run a windage try, the only thing that ramps up quicker in a 400 than piston speed is windage. I will let others comment on your cam, ANY cam suggestions will need more info to match it to the short block. I do know this, its going to take a huge cam to spin that many rpm and then your just losing low end. Low end is sorta what these engine where built for.

 

I agree with kopfenjager - there are too many good heads out there to waste time with Speemasters. And the rest of it too.

 

Two things: First make sure that a standard 351M/400 intake will cover those head's intake ports. If the intake ports are the so-called 3V port they probably will not. Second, neither of those intakes will flow enough to allow it to make power at 6500-7000 rpms. I recently "fixed" a 351M where the customer was conned into aftermarket heads that did not work with a 351M/400 engine.