I have searched and not able to find if the IS350 ring and pinion is the same size as the SC r&p and will it bolt to the SC differential. Basically I'm needing a 4:08 ratio, the SC4:08 is scarce, the IS350 4:08 is plentiful and cheap. No need to discuss setting up gears. Thanks in advance for the help

 

I have never heard of the IS350 ring and pinion being compatible. This a new one to me and I just don't know.

However there are two other sources of 4.083:1 differentials for our cars: the somewhat rare 1997-1998 Supra Base/NA Non-Turbo diffs (manual and auto both had the same 4.083 ratio for those model years in the U.S.) and the 1993-1995 GS300 also used the 4.083 ratio.

Also if you count JDM Soarer 3.0GT's which had 2JZ-GE Auto drivelines I believe those came with 4.083 ratios but I could be mistaken. Similarly the JDM MKIV Supra NA's apparently got the 4.083 ratio across the board.