Lowest possible rear differential ring and pinion

[ThunderZTA]

Hey everyone,

Ive been hunting for some time now to try and find the lowest rear end ratio possible for the MKIII supra since i will be switching to a TH400 transmission soon

I currently have the OEM 3.91 gears my 1988 came with.

The lowest ive been able to find that i am aware of are the 3.58

I think I may have found a set from nitro that are 3.54 which is really just 100 RPM extra.

If my current calculations are correct; my max speed with a 3.58 is 162 mph using; speed x rear gear x 336 / tire diameter

162 x 3.58 x 336 / 28 = 6960 RPM

I am needing to see if there is a lower geae set out there that we can use so i dint have to change the whole pumpkin out if possible.

I attached photos of the 3.54 nitro gears in hopes they are usable and some info i saw that there is a 3.07 gear set in 80s 4runners that inam hoping are compatible. My understanding is its a g662 diff code that is also an 8" rear end but only 2 pinion open vs the supras 4 pinion LSD


Any help is much appreciated!!!!

 

[Zazzn]

I just installed the 3.54 from nitro, I had Wierperformance put it together with the max grip kit. We'll see how the car runs with it, but the biggest issue will be the Speedo mechanical gear I found one but it certainly won't be perfect.

BTW the nitro gears are used out of a Toyota truck. I ended up buying a 4 Cyl truck ring and pinion that was 3.54 but didn't work. Ended up buying directly from Nitro in the end.

 

[Piratetip]

Yep. Not all 3.54 gears will fit.
3.58 is easier to fit than the 3.54 which requires more work.

The Turbo A vehicles back in the day got a custom made tall ratio gear.
I believe it was 3.2, but its a super rare part.

 

[ThunderZTA]

BTW the nitro gears are used out of a Toyota truck. I ended up buying a 4 Cyl truck ring and pinion that was 3.54 but didn't work. Ended up buying directly from Nitro in the end.

Do you by chance remember who you spoke with for the 3.54 gears at nitro? Id like to get a set myself

 

[ThunderZTA]

No one else has an idea on here for lower gears than 3.58 without switching pumpkins?

 

[Piratetip]

3.54 is the only other option, its not a simple drop in part though as the 3.58 is.

Unless you work with Nitro or Yukon to engineer and create a new gear ratio, no there is no other options.

Ask Supraclaou what he thinks of the 3.58 setup I sent to him, I believe he is matching it up with a MKIV 6 speed trans.
I made and sent out 2 other 3.58 setups for other individuals as well.

 

[Zazzn]

it's not the pumpkin, i switched the ring gear. but you can also switch the 5th gear in trans for a truck gear. that's about all you get though.