400 stroker question

[Bobby Goolsby]

I am wondering if a forged steel crank from a 440 will work for my 400 stroker build? I can get it for $350 is why I ask. It is an Eagle 4340 - 44037506760-6. Or should I just buy a stroker kit from 440source?

 

[Curiousyellow71]

The 440 mains will need to be turned down to 400 size and the 400 also uses a smaller counterbalance which will require block modification or trimmed 440 counterbalances. In most cases it is simpler to get a new crank that fits, but thousands of 440 cranks have been modified to make a 451 out of a 400. Finding a machine shop that can perform the mods is the next hurdle.

 

[m79ded]

I did exactly that, I took a 440 crank and cut the counterweights and journals put in scat rods and the lightest Ross pistons I could find. The engine revs up so fast and incredible torque. I also say a guy I know did up a 470 with Molnar 3.91 crank and 6.70 rods not like the 440 source kit with 6.535 rods and the same 1.32 piston from the 451 and that thing was incredible. The power it made was outstanding. If I had to do it all over again and I was going to buy a new crank I would do the 470. Or else a 451 will be great. Good luck on your build

 

[kramer]

Another option on putting the 440 crank in the 400 block is if the main journals on the crank are in great shape is to aline bore the 400 block to 440 bearing size. You have alot more options on what bearings you want to use with the 440 main size or at least is used to be that way.

 

[RemCharger]

Another option is build a killer 440 with it.
That's what it was meant for.

 

[69Bee]

Another option on putting the 440 crank in the 400 block is if the main journals on the crank are in great shape is to aline bore the 400 block to 440 bearing size. You have alot more options on what bearings you want to use with the 440 main size or at least is used to be that way.

I think boring the mains out 0.125" today is a bad choice. There are cranks available that will drop in, or you can spend about the same amount of money turning the crank mains & throws down on a 440 crank. By cutting that much out of a block, you are moving the main bore 0.0625" closer to the main cap bolt hole, and need to maintain a 5.152" cam/crank centerline in the process. Again, in todays world of available products, getting a drop-in stroker crank would be better, and possibly less expensive in the long run.

 

[m79ded]

I am wondering if a forged steel crank from a 440 will work for my 400 stroker build? I can get it for $350 is why I ask. It is an Eagle 4340 - 44037506760-6. Or should I just buy a stroker kit from 440source?

If it's in good shape and not cracked buy it. The price is pretty good.
Cut it down to fit 400 get lightest piston you can and rods and you'll be very happy