Im wanting to go with the 351m/400 powerplant in my truck. I have the original 351m that it came with. It runs fine. I plan to do a mild performance build on what ever I do. All the usual stuff. Intake, cam, 0degree timing, tube headers, etc. Maybe even throw some TMeyer Inc money into it.

Am I better to start off with a 351m block or start looking for a 400? I have the 351m already so can I use that and update it to the 400 internals easy enough and then continue my build? Thoughts? I probably can buy a 400 for a few hundred dollars...maybe thats the better way to start?

 

Just keep your 351M, it's the same block as the 400, the only difference is the crank and pistons. The rods are the same. You'll need a 400 crank and pistons from Tim Meyer if you want more compression and power. Get your block machined so you know what oversized pistons you'll need and then call TMeyer and get them to send a crank, pistons, and engine kit (oil pump, bearings, gaskets, timing set, etc), intake, cam, anything you will need to get started with your build. Ordering everything from one vender who knows these engines as well or better than anyone will probably make things alot better for you. Good luck.

 

Nothing against Tim or his products whatsoever, but you could save some money by buying a 400, and just using the crank from that, or just a crank if you can find one. You can get a 400 for 200$ no problem, I helped a guy tear one down recently when I needed a crank, and he gave me it, 3 heads, and a little grab bag of other stuf for 160$. Pistons though buy from Tim, if you want to go that far with your rebuild.

And yes, the 351M and 400 blocks are exactly the same, a 351M block is a 400 block.

AleX