First thing would be the main bearing journals on the 413 are larger than the 400, so you'll either have to turn down the crank or bore out the block. Most folks turn down the crank, as they're still plenty strong (even cast) and it leaves the block at 100% strength. You'll then have to make sure the crank counterweights fit in the block bottom end. That would take turning the counterweights down, or grinding on the block (or both). It shouldn't take much, but I don't think it's a drop in. After that, it's just picking the parts to work with your engine. You can probably recycle your 400 rods, or you can get new 440-length rods to use, Keith Black has pistons to work with both setups. You might want to poke around on 440Source.com to see what they've got to say about the operation. You can also get whatever other parts you need from them, as they specialize in big block strokers.
Joined: Mon Jan 16 2006, 02:52AM
Location: Vantaa,Finland
Posts: 379
No welding needed. The rod lengths are 6.76" for the RB block and 6.358" for the B. So, with RB block your pistons will be 0.4" shorter and therefore lighter. With the lighter pistons, you'll stress the rods less, and teh engine revs quicker + puts out a couple of more hp's. No need to go for a 1/2" because of the stroker crank, but doing it will help hte oil supply to the pump, and is recommended for higher rpm usage. Here is a couple of articles worth reading: http://www.arengineering.com/articles/451.html http://www.arengineering.com/articles/ttstroker.html
Joined: Sun Oct 22 2006, 09:26PM
Location: San Antonio
Posts: 74
Make sure you have your rotating assy. balanced by a competent machine shop. If you plan on making some "real power" there are some mods that need to be done to the blocks oiling system to help it survive. I have a 451 (which is what you are building) and currently building a 500, both based on the lowdeck 400 block. I have built 13 mopar BB strokers so I have an intimate relationship with this setup. Now y'all know where my screen name comes from.
Joined: Sun Feb 05 2006, 11:51PM
Location: Pa
Posts: 3064
Corey - I would cozy up to lo deck and listen to anything he has to say....he's got the 'sperience !thumb
Welding the rod journals is to increase the crank's stroke to even longer lengths than the difference between your 400 and the 413. Then they are offset ground back to the rod size but now live a little "north" of their birthplace.
I agree with Clair on the turning down of the main journals to fit your block. Better strength and oiling (ya still gotta enlarge to Hemi 1/2" oil pickup tube size!) , and a little less weight in the rotating mass couldn't hurt either....
BTW, what C.I. displacement/ stroke should he shoot for on a street-strip motor lo deck? I remember Mopar Action did a 383 into a 452 and they used chevy parts (BLASPHEMY!!!) inside. Custom Ross pistons too IIRC......
!drive
<span class='smallblacktext'>[ Edited Fri Oct 27 2006, 01:40AM ]</span>