Has anyone installed billet caps on a 440?

[TIMINATOR]

I have:
3 billet main cap kit
5 billet main caps kit
5 billet main caps with cross bolted center 3 cap kit.
Has anyone done the crossbolted caps?
How about experience with reliable street HP levels of the different caps and stock caps with ARP studs, which I will use with any caps I go with.
My goal is a street driven 72 Challenger with a 512 TFS headed solid roller motor to run 9 anything on the motor, and then stick My 300 HP plate on it and see what it runs.
The trans, rear, and chassis are done already, as is the roll bar. I'll make a trip to the track and see if I get booted for a 9 on the motor once it's sorted. Then put the plate on it and go to a different track and get booted for whatever it runs.
Thoughts on the caps?
Am I overthinking what it needs for caps?
I'll sell whatever caps I don't use, I just want all my options covered before it gets machined.
Big single plane manifold and HP 950 Holley.
Cam will be a Comp Cams solid roller about 272 or so at .050. Ported TFS 270 heads. Compression about 11.0 with Race tec or JE pistons
Billet liteweight 8 bolt aero crank.
Billet 7.1 rods.
Built 8 3/4 w axles, SS type springs (now), or Cal Tracs, relocated front spring perches.
Goal is a fun, limited street, occasional track car.
I'm thinking the 512 should do around 700 HP. Oh yeah, I will half fill the block too.
Thoughts, comments, or suggestions?
TIMINATOR

 

[Xcudame]

Although I haven't used anything other than stock main caps (everything has been less than 550hp), the cross bolted main caps (think Hemi) would make the most sense. The big block Mopar will live easily at 600hp and under. 800hp and above, there's likely to be catastrophic failure in the main cap/web area! You're in that gray area in-between, which is probably you're reason for concern. Some engine builders swear by aluminum main caps up to 800hp. Since you have a machine shop, I think the best option with the parts you already have is the cross bolted kit. I believe the Hemi block was good for 1000hp stock, so you should be safe.

Might want to consider a Dana 60 for the rear!

 

[TIMINATOR]

If I break the 8 3/4, I will upgrade then.
As an interesting side note about the 8 3/4, years ago I ran a Super Comp dragster, 427 brodix headed, [email protected] solid roller Chebbie, glide, 5500 stall with trans brake and 4.10 gears with a 1 3/4" pinion. It ran 8.40s @ 167, but I wanted a better 60 foot.
A friend had a set up punkin with 4.30s so I stuck my spool in it and ran it. He said that he thought it had a 742 pinion 1 3/4" gearset too.
After I had made 5 passes on it, then he tells me he knows it was a 741 REAL SMALL pinion gear from an old 6 cylinder van! I think those were 1 1/2" pinions....
Anyway, I ran it like that for 3 more Friday nite grudge races and 1 divisional, and never broke it! I put the new gears in my other punkin, and my friend sold the small pinion setup to a guy with a low 12 sec. Duster, who ran it for a few years and sold the car.
Had I not seen it, I would never have believed it!
My pal figured that I would get a pass or two and see how I liked the 4,30s before buying a new set. He said that if I knew they were a 741 set, I never would have tried them. He was right about that!
TIMINATOR

 

[Xcudame]

I truly believe the stock factory 8 3/4 is tougher than any stock factory Phord 9 inch that everyone (non-Mopar) seems to rave about! And the 741 actually has a 1 3/8" pinion. So maybe you're experience backs up the strength of the 8 3/4!

 

[TIMINATOR]

I think the strength of the 9" has to do with the 3rd pinion bearing on the nose of the pinion, supporting the pinion from both sides with 3 bearings. The 8" has the same deal also. I have not broken any of those rearends, but I have seen a 9" years ago with the punkin case cracked at the pinions nose support. I prefer the 8 3/4" to the 9" because of the 8 3/4" has a smaller hypoid distance, allowing less of a HP loss, and the fact it is lighter overall than the 9".
The only gearset that I have broken was a 7 1/2" in my street/strip Regal with a 11 to 1 built 350 chebbie and 4.56 gears. With the 4.56s the pinion has only 9 teeth as I remember. The car ran 11.50s with the front wheels about a foot to 14" in the air.
With the 3500 convertor it ran for about a year before spontaneously removing ALL of the pinion teeth. I replaced the gears with a set of 4.11s (10 tooth pinion) and never hurt it again.
I am no fan of the Dana 60, as it too has a very deep (even more than a 9") hypoid distance, and has an even heavier deadweight than the 9".
I believe that quality bearings (Timken) and Richmond gears along with a perfect contact pattern are more important than type of rearend.
TIMINATOR