[oldman]

So AFAIK the zl1 cradle (diff, driveshaft, axle shafts, brain, brakes etc) bolts right in, the problem has always been the brain located in the cradle not talking to the SS ECU, drivetrain module cambus or whatever... I don't think the SS brain even talks to the SS dif at all, the ZL1 brain definitely talks to the diff. Anyway here is my thought. Assuming Nitro gear is correct and their LSD works for ALL years of the ZL1, I could just put this LSD into the ZL1 diff and then bolt the whole cradle into my SS and run the SS brain (or whatever it is called maybe traction control module). My reasoinig is the ZL1 diff with a mechanical LSD is basically a SS diff as far as overall working just a whole lot stronger and a whole lot cheaper than a 9" drop-in. Thoughts??

Here is the LSD says 13+ ZL1
https://nitro-gear.com/gm-250mm-nitr...zl1.html?q=zl1

[Bumbleboy92]

The part about the SS not talking to the diff is true, my transmission chart can show that while SS’s have LSD, the ZL1 coupes have eLSD. Hence the computer talking to the diff on ZL1. The exception is within the SS 1LE which also have eLSD.

Seeing as you have a manual, to change to eLSD diff would be from a ZL1 manual coupe (same 3.73 ratio as your manual SS but with eLSD), though the ZL1 manual convertible has the same 3.73 but is not eLSD. If they didn’t just reuse diff’s from the SS, then ideally that would be the route to take since it would be the exact same 3.73 LSD diff but with stronger internals.

I do not know if they reused the diff or if it’s a entirely different part for the ZL1 but I would contact the company and speak to them, they can most likely walk through and see if it’s possible. Otherwise I’d suggest looking into if the ZL1 convertible diff is actually stronger or just the same SS diff. That should be plug and play since no computers and it’s the same ratio as the SS

Edit: also just realized that the gear ratio is different between the regular SS/LT1, ZL1, and ZLE. I'm unsure what they are for the 1LE variants.

[Kerry]

Will the convertible zl1 diff bolt into the ss cradle? I know its beefed up as at least where the axles bolt to the diff

[WhiteMale]

The 1LE is a 3:73 ratio, but I'd swear the ZL1 is 2:85.

[KingLT1]

Originally Posted by WhiteMale

The 1LE is a 3:73 ratio, but I'd swear the ZL1 is 2:85.

It depends on the transmission. A10 is 2:85 rear, M6 is 3.73.

[WhiteMale]

OK yes, but I just woulda thought a 3:73 in a supercharged application would just destroy the tires.

[arpad_m]

Originally Posted by WhiteMale

OK yes, but I just woulda thought a 3:73 in a supercharged application would just destroy the tires.

Correct me if I'm wrong, but I think the idea behind 3.73 may have been that the clutch would take up some of the shock and soften the "ramp-up" as nobody will want to dump it in a ZL1.

[Joshinator99]

Originally Posted by arpad_m

Correct me if I'm wrong, but I think the idea behind 3.73 may have been that the clutch would take up some of the shock and soften the "ramp-up" as nobody will want to dump it in a ZL1.

Gear ratios in the M6 are different than A10 so I’m assuming that was the thought process. Since the A10 has a very steep first gear you can get away with a numerically lower diff and keep the same low end acceleration as an M6/3.73 combo while gaining MPG on the top end.

[KingLT1]

Agreed! As Josh mentions you have to consider the transmission ratios as well. The A10 with 2.85's is more aggressive than the M6 with 3.73's.

[WhiteMale]

Thanks for the education