teddyjr

I'm finally to the point of dropping the subframe to upgrade the diff/axles/brakes/hubs for my autocross/DD Kouki S14. I've been reading the forums for months about the Q45/J30/Z32 combinations and have acquired and firmed up everything to complete this part of my RB25DET swap. I have the later 3.69 Q45 diff unit with a set of early Q45 6-point outputs and the TT/Q45 axle combo and the big hubs and Z32 ebrakes (and a finned cover!). I plan to swap the too-big pinion flange when I do the front seal.

Which comes to my question: what ratio - 4.083 or the native 3.69? I know the 97 Skyline ECR33 my motor came from has the 4.111 so it seems like I'd want to match the OEM setup. This is not a drift or drag car as much as a DD for occasional auto-x or Sebring track days. The most HP it will see may approach 300 so it will stay mild and OEM. I'm just looking for opinions/experience 'cos I want to set it up once and drive it so I can start another project. I'm not looking to "try them all" and I really feel that anything over 4.083 won't suit Interstate or track day driving.

I've got all the parts to go either way and a reputable shop who can set up the 4.083 if I go that route. I know I'm sort of answering my own question but I feel I need to "put it out there" before pressing play. Thanks in advance! - Teddy

Update: Went with a Z32 diff and early J30 axles and sold all the Q45 big spline stuff off today. The Z32 R200 diff will more than handle a stock RB25DET and the J30 axles are a tad thicker The guy that got my big axles will be running 600hp so he'll need these.