ABout the main caps..Milodon makes ductile iron caps. Aren't they any better than the alu ones ?

Dan

They advertised them still but they don't sell them any more, steel or aluminum only
Mopar use to sell ductile iron main caps a long time ago like Milidon did, no more, same thing at Keith Black
BTW, DO NOT go to cross bolted main caps and girdles That weakens the heck out of the main webbing and it is a big waste of time and money
A good set of aluminum main caps and ARP main studs in a good sonic tested 400 block and your good to go up to 850 HP

BCR Aluminum Main caps are the way to go.

Eagle makes a .250 long, 6.385, chevy rod that is chrysler width, 1.007". part# 6385C3D. KB icon #IC-824, 1.660 CH X 4.375 bore, would work for pistons if block would clean up at 9.995". A good machine shop could spin .010 or .015 thousandths from top of pistons if needed, or a thicker head gasket could be used. I know plenty of guys run with the wide side clearance but I prefer not to. If it was acceptable the factorys would have made them with more side play. I have a 383 with the 6.385 rods and 3.900 stroke that made 675HP +/-, at 10.5 to 1 CR with 915 heads. Broke the camshaft at 1300 passes and bearings looked almost new. Also, aluminum is good for cylinder heads and beer cans, not so much for connecting rods and main caps. Unless you want to spend another $800 for caps, line bore and hone + bearings, rings, etc. after a few hundred passes. I would have to do tear my junk down at half season to replace them. I don't plan on a freshin up until 1000 or more passes. My 2 cents

Google SKMFX engines in Summerstown Ontario. Jesse has build some pretty stout 471 and even entered one in the Engine masters challenge.
613-931-2157 ask for Jesse

Using the BCR aluminum caps and 1/2" thick girdle on the 400 with 4.150" stroke (499", but I call it a 500" stroker.)
The machine work to align bore and hone the caps and mill the caps and oil pan rails flush can add around $500+ in machine work plus the cost of the cap/girdle kit.
I'm maybe in the 700 HP range with the engine?

It would be nice if Dart or some other manufacture would produce stronger aftermarket Mopar blocks for the cost of the GM blocks. Even the more expensive Mopar Mega-blocks are hard to find and are selling for 2x or more the cost of the GM stuff.

Had the VP from Milodon here this week. No more ductile iron caps from them but they are tooling up for 4340 caps very soon. Same thing for KB. The new caps for all blocks going forward are 4340.
Todd