lslade

I picked up a cheap 4.27 diff out of an sc300 on CL and popped it in my 93 sc400 with about 150k on it.

There was some bantering on whether or not this was worth doing, I'd say yes.

My rev's are only up a little bit on the freeway, but the car is much more lively off the line, it will spin the tires pretty readily now where it used to just kind of churn them around a little. I also kind of dig the higher RPM on the freeway, more power on tap without a downshift.

This car is kind of a beat around car for me, so ultimate fuel mileage is not a concern, I'm sure this will go down slightly, but I can't see it being anything drastic.

The wheel speed is correct, speedo is in the hub...like the other guy said.

Do it. You'll like it. The swap is few hour job, not super easy but not hard either. Get a nice set of allen sockets and have a real nice jack.

Suplex432

I was curious I have a 1997 auto sc300, correct me if I'm wrong but I believe it comes with 4.27 gears? If so Wuts the max mph can I get out of these gears?

lslade

Yeah you have 4.27's already. The diff I bought was out of your exact car.

The transmission in the 300 is geared differently from the factory than my 400, so I'm not really sure what your ultimate max speed is, but I'm sure there is someone online that knows...just ask google : )

Probably 140 - 150 with enough room. Pretty low CD with these cars.

Make sure your tires and brakes are solid and you have plenty of room and a clear freeway before you go blasting around at high speed though man. Things get out of hand quickly over 130 or so...