Has any of the 400 guys used a 300 Auto Diff? Seems like a decent upgrade, the stock 400 gear ratio is 3.92, and the 300 auto has a 4.27.

From what I've read the pumpkins are the same. Anyone think it'd be a worthwhile swap?

 

https://www.clublexus.com/forums/sc-...rset-swap.html basically the same thing...

in my opinion unless you cars is for track or something seems pointless

 

HY!

I have installed the 4.08 with LSD (from a Supra TT) from the MT SC300 (Supra mkIV NA) and its perfect, shorter is too much, the gears are too short with the 4,27, or you will go on track, but with the 4.08 is the performance perfect.

greets

Tom

 

Why do you think the 4.27's are way too short?? Doesn't seem that much of a difference between the stock 3.92 to 4.08.

 

HY!

Easy calculation:



You loose in last gear 13,63 miles. this are 500u/min higher. i find, this is very much! With the 4.08 you are 240 u/min higher. I drive with the 4.08 and its okay, the car feels every second ready to race. When you drive 60 miles and more, you have more engine brake, the car rolls not so easy as with the oem ratio.

Have anywhere installed a 4.27 in his SC400?

greets

Boergsn

 

Ah!

So the engine RPM's are much higher at a cruising speed? Do you happen to remember what the rpm's were with the 4.27?

I've been doing a lot of research, I almost have all my parts for my w58 swap, so the gears are going to be much different once I do that swap.

 

The sc400 wakes right up with this gear ratio and if most of your driving is in town then go for it !

 

nah, unfortunately I'm doing a little bit of both, but mainly town. I'm still deciding lol

 

It is liveable on the highway just not for 800 mile trips, It really brings the car to life from stoplight to stoplight.

 

I think I'll give it a shot, there's an SC here at the pick and pull so I might just give it a shot to see.

 

Unless you live in the middle of manhattan getting into 4th (final) gear on the 400 is easy.

Trying to overgear a weak car for more power is a pitfall attempt at performance. If you don't track the gains won't be relevent. Eventually you'll slow realize that you're just burning extra gas for nothing.

 

sc400 diff 3.9
sc300 diff 4.11
(us spec) na supra diff 4.27
(jap spec) na supra diff 4.11

you will need an electronic speedo corrector
revs 2500 @ 108kph to 2700/2800 @ 108kph (sc400 to sc300)

4.27 diff would be good in a track car where the fuel is not an issue.

my view dont bother changing the diff.

the best conversion to get closer speed out of each gears would be convert to an r154 gearbox with os giken 1st to 3rd ratio change

 

Lol,

I'm actually converting to w58, it's much easier to get the parts to swap to w58, plus the transmission is a lot more smooth compared to an r154.

 

Yes smoother and weaker

 

usdm sc300 auto is a 4.27 gear and I should mention I shave 1/2 second off 1/4 mile time with this swap.