Quick question about the Diffs.

[Gumby83]

So, i read up on the various different diffs available for swaps with the accompanying information and still couldn't find a answer to my question. My question is since from what i read the main point of diff failure is spider gears from a open diff, does that mean a welded R180 is as capable of handling 600ft/lbs of torque? because from what i read there was a limit, r180 was about 300 ft/lbs, r200 was 400+ and R230 is apparently retard strong. also, would a R230 reduce ground clearance?  Would a clutchpack increase the amount of torque a diff could reliably handle? thanks

[Zfan1]

I am running an R200 LSD out of an 1989 300ZXT with added clutches. My 1970 240Z has had between 550 rwhp and 700 rwhp for yrs and runs mid 9 1/4 mile passes and has never broken, cv axles have but not rear diffs.  I had a r180 in mine yrs ago and it went boom the first time I hit it with 300 rwhp.

[RebekahsZ]

Impact and wear are the enemy. On an open R-whatever, the cross shaft wears and allows the spiders to get out of alignment and they they get into a locked (like a vice) configuration and one wheel stops turning and an axle snaps, then the car will at least roll again, but not move under its own power (cause the open diff just free-wheels). Automatic trans is much much more gentle on the driveline than a manual trans because you can load the driveline by foot-braking, thereby pre-loading the driveline and removing much of the slack and associated impact from the system. Add a trans brake and you can expect the reliability of a manual trans again. Go to a Powerglide and you have only 1 shift after the launch, so that really reduces impact cycles, vs. a 4 speed manual which over the same 1/4-mile will experience 4 (twice as many) driveline impacts over the same driving distance. I still haven't met the guy who has broken a CLSD R200. We break driveshafts, outer stubs and axles. Axles being the most common failure. Stock axles at the u-joint, Z31T CV axles at the splined portion that inserts into the diff, Wolf Creek CV axles have trouble with the adapter bolts getting loose. Chequered Flag Racing had a prototype 930 CV axle with heat treated chrome moly stubs, but I think the combination of production cost and low demand killed that promising venture. Welding the diff solid tends to be very hard on axles with big sticky tires being the exacerbating factor there. Good luck!

Edited September 5, 2016 by RebekahsZ

[crapforum]

My R180 and stock crappy axle u joint things have been surviving my 400whp motor. I never have dumped the clutch, and I roll into the throttle from a stand still. Tires will start to spin if I give it to much gas to soon anyway so I'm not going any slower. I think so long as you don't want to drag race you can get by on anything.