I have looked everywhere and can't find steel main caps for the 4.6 DOHC. I keep hearing about 1,000HP, 1,200HP motors and can't believe they are running the stock, iron, 6-bolt caps. Does anybody make steel main caps for the crank?

 

Never heard of them.

 

MMR would be the ones to ask about that. They run 2k+ with the cast caps

 

Apologies for the delayed response. I have been literally off-the-grid the past weekend . . . no communication of any kind.

Thanks for the replies. I'll check with MMR. I have seen some really nice crank girdles and dry sump setups but no custom bearing caps leading to the possibility they are not needed.

 

I talked to Taylor at MMR and he says they don't offer such an item. Pretty unbelievable that a stock cap can contain some of the HP numbers I am seeing. But if MMR doesn't stock it or make it, then it is probably not needed.

THANKS to all for the replies.

 

Especially considering they are running 2500hp on stock mains.

 

I have heard all the HP numbers and some dyno videos and run sheets are credible. But I have not seen pictures of a bottom end that can take that kind of HP. Raw HP numbers are pretty easy to confirm or dispute. But a bottom-end build is very difficult to verify. The caps are much narrower than a SBC or SBF and appear weaker. But I know alloy, geometry, and dimensions all contribute to strength. It my lack of experience with the DOHC that is causing my doubts.

 

It could be taken with a grain of salt but from what I understand from some guys at ford over the years is that the nickel content, geometry, and the use of side bolts rather than extra vertical bolts are what make these modulars the cats meow for power.

 

Like mentioned the 4 bolt mains with side bolts are extremly strong in these motors.

 

I appreciate the replies and interest in this thread and my replies are not meant to be argumentative. I'm new to the 4.6 and I'm trying to wrap my mind around some of the forces and the engineering. Some of the HP numbers are incredible . . . I'm not saying unbelievable. What I'm saying is I find the structure holding all those horses together pretty unbelievable. LOL

1,200 - 1,500 HP means 5,000 or 6,000 lbs. of force trying to push the crank out of the bottom of the block! Holding it all together are a few 8mm bolts. Yikes! A '6' bolt main sounds nice but adds little strength. The side bolts are horizontal to the vertical load and are there only to position the crank in the block. They don't add any tensile strength. They are a 2 piece assembly composed of a jack-screw (torqued 7-8 ft. lbs.) and a bolt (torqued to 14-17 ft. lbs.). It all looks nice with the deep, extended block and the cross bolted mains but when I pick up a scrawny 8mm bolt I cringe. I have a lot to learn . . .

 

To add to your amazement there are guys running stock crank shafts without counterbalances at 700-800rwhp level as well.