If you're starting from scratch I'd just start with a
Dana-60 or even better yet an S-60 from Strange Engineering
For the $$$ spent, might as well go with a Dana-60
after all is said & done...
for a near destructible best parts available 8.750" rear
An alum. MP 742 carrier is $1000+
a trussed Fab carrier housing is $800+
a spool is $200
gears are $180- $250 depending on what brand, style or what ratio
or a diff. is $450-$800, depending on what type or who's
axles are $200 ea. or more depending on who's
green bearings etc. are $100+ {?}
it can get to well over $3000 before brakes
about the same $$$ or more than a S-60 or Dana-60 race ready
I had a 8.750" solid mounted in a old altered
solid mounted they are abused severely,
a car/combo that had a 1500+hp blown alky combo,
among a bunch of different blown or injected engine SB & BB combos,
albeit light car, org. built to have it weight with driver come
in at 1800lbs wet, I was concerned about weight
anyway it was trussed, had thicker 0.250" {x 3" ?} thick tubes,
full floater alum./steel ends {much like a truck Dana-60 has},
org. had Lenco full floater axles, after I broke one
I found some special "astroloy" materials {spelling ?} axles,
that was my weak point
I had a machinist I knew cut & spline some axles to fit my needs
it had either Wilwood or Baer Brakes {I can't remember which}
anyway;
It went 1.0 60fts or better regularly, ran hi 6's in the 1/4 @ 190+
both with an auto with a trans-brake 5500+ stall converters
& a Crower slipper clutch hard launched with a 3 speed Lenco
most of the rear end race components were from Lenco back then too...
I added some ballast, an onboard starter, a big battery, seat padding
& fire system 2 bottles etc.
it ended up being over 2200 lbs, & 2500 lbs with a Mastodon Hemi,
to meat weight per ci requirements & it lived very well, but still a light car...
Never broke the gears, bearings or spool or anything inside the carrier,
for well over a decade, just checked &/or replaced gears/bearings
& wear regularly, mostly just a check a couple times a season...
I would put about 120-150 runs a year...
I did break an axle before, I can't remember the spline count or size
I want to say 35 spline on the carrier side & 18 {?} on the floater side
I went to the fancy dancy extremely tough astroloy {spelling ?} special
light stronger material NASA used at the time, for shafting materials,
for my axles, that problem was solved...
Re-inspected regularly...
Now;
If I had to do it all over again I'd have done a Dana
not worry about the extra 50 {?} or so Lbs,
easier to find race oriented type parts for too
IMO The flex in the housing or bending/twisting axle tubes
is probably the biggest killer, in an 8.750"
replace the crush sleeve with a proper sized/material
machined spacer IMO is a good Idea too,
if you stick with a 8.750" ring & pinion
I went 8.56 @ 158 on 300 shot of N20 in a 3520# 68 RR
with a 8.750", a 742 Nodular carrier 1st then a 742 Alum. Carrier
the car was a 315 drag radial car, with Calvert CalTracs
for over 10 years it lasted being abused with 700+ hp or more
ran 9.70 N/A in street trim & it lived just fine,
it also had many of the same type parts as listed above
Like I said before If I was to do it again I'd go with a S-60 now
I hope some of that helps
novel complete...
