Brendon

iTrader: (1)

I've been looking at options for converting the SC400 (1UZ, not 2JZ) to manual. As of now, it seems the only real swaps people have done are the W58 (most popular), R154 (less common), and the V160 (Scotturnot is the only one I heard who's done this swap). The problem I'm facing is finding a tranny-differential combo that works for me. I'm looking to improve acceleration, but without sacrificing fuel efficiency and wear-and-tear on the highway (i.e. running at a higher rpm).

This severely restricts the W58. Because of the W58's gearing, the rear diff would have to be 3.53 or less to keep the highway RPM equal to or less than the SC400's stock 4-spd A340E. This restricts the W58 almost exclusively to the 3.27 diff found in the Supra turbo and the 98-00 SC400. With a W58-3.27 diff combo, 1st gear would be 2% taller than stock, making launches off the line slower. Also, 2nd gear would be almost no improvement over the A340E. The would make this swap less somewhat fruitless.

The R154 is more more flexible. Running the Supra's 3.76 diff behind it would keep the highway gearing almost the same as stock, while giving an 11% improvement in 1st gear. The problem with this combo is 2nd gear would be 4% taller than than stock, which would hurt my mid-range acceleration (from about 40-80 MPH). This combo would probably be worse than the W58 because most acceleration/races occur in this range.

The V160 is by far the best overall. Coupled with the 3.27 diff, it improves across the board. 1st gear improves by almost 14%, 2nd gear improves by a whopping 29%, and highway cruising RPM's actually drop by over 7%. The problem is the V160 is VERY expensive compared to the other trannys, and it would require custom fabrication to hook it up to the 1UZ due to the lack of support.

Because of all these problems, I've been looking into the less common R155 and W59, trannys used in the RWD Toyota Tacoma. Their gearing is much more suitable for my desired result. Being trannys designed for trucks, they have very short 1st and 2nd gears to put more torque to the ground. Even when coupled to a 3.27 diff, they improve 1st and 2nd gear acceleration significantly. The R155 improves in 3rd gear over stock by 20%, giving it a further boost for races beyond the 100 mph mark. Highway cruising wise, the W59 remains close to stock and the R155 actually reduces RPMs by about 4%. Has anyone ever considered these two trannys? I know there are a bunch of kits out there for hooking up the 1UZ to the W58. Would it work with the W59?

BartleDoo

iTrader: (1)

Why are you worried about wear-and-tear? This is a 1UZ! Also, you're not factoring drive-train loss into your calculations. Order of loss from lowest to highest being W58<R154<V160<A340E. And the fuel economy was never good but doesn't really change that much from stock with a W58.

VanillaSC

BartleDoo what diff are you using on your car? Just curious...

BartleDoo

iTrader: (1)

Stock 3.916 open. I eventually want boost and then I'll go with taller gearing but I definitely won't consider a taller ratio while N/A. I would like a Torsen LSD sometime soon. Open diff sucks!

hovsc400

wht are crusing rpm range on a w58 swap in a 400

Brendon

iTrader: (1)

W58 @ 65 MPH
3.27 (Supra, SC400 98-00) - 2162
3.62 (LS400) - 2394
3.76 (Supra) - 2486
3.92 (stock) - 2592
4.08 (SC300 manual) - 2698
As a point of reference, stock with the 4-spd A340E, its 2334 RPM

Calculations come from: http://www.csgnetwork.com/multirpmcalc.html

This is why I'd opt for the W59 if possible. I generally cruise on the highways at around 75-80, which would put me over 3000 RPM on everything except the 3.27 or the 3.62. The W59 is nice because its got short gears designed for a truck. If you couple it with a less aggressive differential like the 3.27, it keeps the highway revs low while still keeping 1st and 2nd gear acceleration very snappy. Can anyone give me some honest input on the W59. Is it compatible? Is it reliable?

account2x

iTrader: (5)

I think you have already realized this but all those transmissions you are looking at (including the v160) were designed for low low-end torque 6 cylinders. What you are really looking for best be suited with the 5 speed AUTOMATIC (A650E) transmission found on the 98+ SC400 and GS400 along with the 3.27 rear end.

Brendon

iTrader: (1)

oh I guess I forgot to mention I hate automatic

account2x

iTrader: (5)

T-56 ?

mtnrat

iTrader: (1)

I have the W58 and just put in a 3.26 into the 3.76 LSD i had in it. I found the W58 3.76 combo too short for hwy driving. It was fine around town. The 3.26 has exceeded my expectations. The Get up and go is much better than when I had an auto, and hwy cruising is great. I will let you know more soon since I am gong on a 3000 mile road trip. If you look in some of my posts you will get some more info. Actually with the W58-3.26 combo the off the line launch is much quicker than the auto slush box, so no worries there.

account2x

iTrader: (5)

It is 3.27 not 3.26.

W58 1st 3.285:1, 2nd 1.894:1, 3rd 1.275:1, 4th 1.00:1, 5th 0.861:1
A650E 1st 3.357, 2nd 2.180, 3rd 1.424, 4th 1.000, 5th 0.753

The A650E may be an auto but it ain't no slush box. The gearing is more aggressive for a V8 making it faster and better MPG on the highway.

I wouldn't be looking into any of the JZ transmissions for the UZ. The gearing is not right.

mtnrat

iTrader: (1)

No one said it was a 2.26. In referring to the slush box, I was referring to the auto that came with my 92. That is likely the ultimate slush box.

Brendon

iTrader: (1)

I considered the A650E, but if I was going to stay automatic, I might as well go for the bells and whistles, the A761E from the SC430. Its essentially the same as the A650E, but with a 6th higher gear which allows it to be coupled with a more aggressive differential. I assume its compatible to hook up with the 1UZ. What is the drivetrain loss like on the newer automatic trannys?

account2x

iTrader: (5)

The A650E is very nice. I wouldn't call it a slush box like the auto that comes on the 92-96s. I don't know what the loss is but it's a lot lower.

1uz dynos 200-210hp
1uz vvt-i dynos 240-250hp (270 w/ intake & exhaust)

out of that I would say maybe 10-15hp is the intake, VVT-i may only add 1-3hp for your peak power so I'd say the rest is reduced loss.

BartleDoo

iTrader: (1)

The VVT-I may not have added power directly, but it did allow a more aggressive cam profile to be used for higher power up top without sacrificing [and actually increasing torque in] the low end. So, technically speaking, it is definitely responsible for some power gain. I am willing to bet that my manual swapped '93 puts a large chunk more power down than 200-210 though.