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Discussion Starter #1
Don't know how accurate this is, but this guy on Edmunds sounds like he knows what he's talking about. Judge for yourself (thanks to Stanny if it is correct):

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Being a 53 year old gearhead and having some contacts at Toyota, I have as much info as I can get on the new IS300 Manual Tranny. It looks like a brand new design and this is saying something about Toyota. Most manufacturers today do not have the engineers nor the demand to take on the task of designing a new Manual tranny, which costs millions to do today. They must have started this project way before the IS300 was introduced.
So here are the ratios:
1st: 3.566
2nd: 2.056
3rd: 1.384
4th: 1.000
5th: .850
Final Drive: 3.727

Overall, a real "close" ratio box fit for a "boy racer" performance car.
I'd heard that the rear drive was in the 3.80 range, but with this unusual fifth gear ratio at .85 instead of a more common .70-.75, the 3.727 would be more in line to keep NVH and revs lower and meet CAFE standards.

The new tranny is called the W55. It is evidently a Toyota designed and manufactured unit as it is overdrive and the Getrag 220 series is their current RWD five-speed design and has a 1:1 fifth.

The ratios are different than any Toyota I've seen and that probably means a different case - in other words, all new. The old W58 as used in the Supra was quite large, and probably too big to fit in the smaller Lexi.

I don't know what the ratios are in the automatic, but it would be interesting to see if the torque multiplication in each gear is overall similar. There is a chance that the cams in the Manual are slightly different also. More info coming...
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That is all.
 

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here's another interesting bit found on the web from a forum, much like this


The three transmissions of interest are the W50, W55, and W58. The
W58 is the tranny out of the MA61 Supras (1982-1986). The W50 is
partially steel cased, and used in earlier Celicas and the W55 is used
in later Celicas and some 2WD trucks.

TRD published a chart which lists which transmission went into each
Celica. I'll try to bring it to work tomorrow. If you've currently
got a W55 and want to handle more torque, the W58 should bolt right
on. Use the bellhousing from the W55 if possible, since the slave
cylinder was on different sides on the W55 and W58. I'm not sure how
much more capable the W58 is, but it's at least a little stronger than
the W55. I'm not sure how the W50 fits into the torque handling
curve. The W58 is from a car with 169ft*lb of torque, vs. the 140 of
the 22RE.

Alternate gearsets are only available for the W50.
 

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I talked to the distribution manager today, and I specifically asked him if this was the same manual transmission that was used in the SC, and the Supra. He said it is.
 

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If Scoot557’s program is correct, we should see a significant improvement in 0-60 times. Not only are many common losses of the automatic transmission eliminated with manual, but also we DO NOT have to shift to 3rd gear prior to 60 mph!!!
 

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Your topseed program does not take into account the sum of all the drag forces acting on the car. The coefficient of drag for the IS300 is .29
Thus the drag force (roughly) acting on the car for any given speed is
Drag= Coefficient of drag x rho (density of air) x velocity squared divided by 2 x the projected area of the car. Add to that induced drag and skin friction drag (not very large given the speeds we are talking about).

So it is unlikely you will be able to get to 60 mph in second gear without being past redline or that the IS will reach 152 mph on a straight level ground. Top speed is still probably around 140 mph.
 

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the motor will not have to turn more rpms to get to 60 in second gear because of drag. the rpms at a given speed are a constant, no matter how much drag is there, as long as tire size, wheel size, gear ratios etc etc stay the same.

this could play a roll in top speed though, but adding power will overcome that issue, and it should easily reach 153 with some extra power. i must say though, 153 is pretty sad.

Originally posted by sk121_2000:
Your topseed program does not take into account the sum of all the drag forces acting on the car. The coefficient of drag for the IS300 is .29
Thus the drag force (roughly) acting on the car for any given speed is
Drag= Coefficient of drag x rho (density of air) x velocity squared divided by 2 x the projected area of the car. Add to that induced drag and skin friction drag (not very large given the speeds we are talking about).

So it is unlikely you will be able to get to 60 mph in second gear without being past redline or that the IS will reach 152 mph on a straight level ground. Top speed is still probably around 140 mph.
 

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Alright, let's settle this:

2001 IS300 (auto):
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1st: 3.36 (13.25) ---> 34 mph
2nd: 2.18 (08.52) ---> 52 mph
3rd: 1.42 (05.55) ---> 79 mph
4th: 1.00 (03.91) ---> 142 mph
5th: 0.75 (02.93) ---> 138 mph
Final: 3.91

(number between parentheses = gear_ratio * final_drive)

source: Car & Driver, January 2001

2002 IS300 (manual):
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1st: 3.566 (13.29)
2nd: 2.056 (07.66)
3rd: 1.384 (05.16)
4th: 1.000 (03.73)
5th: 0.850 (03.17)
Final: 3.727

2nd gear of the MT is roughly 90% of the AT (i.e., it's slightly taller by 10% if I'm doing my math correctly). Make what you will of this data.

Here's a little more data...

BMW 325i (184 hp, 175 lb-ft):
2nd: 2.52 (7.938) ---> 60 mph
final drive: 3.15

Audi A4 2.8Q (190 hp, 207 lb-ft):
2nd: 1.94 (7.547) ---> 62 mph
final drive: 3.89

Again, these numbers from C&D, Jan 2001
 

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the w58 was in the mk3 (ma70) [86.5-92] and mk4 (jza80) [93.5-98] also.


Originally posted by MajorRugburn:

The three transmissions of interest are the W50, W55, and W58. The
W58 is the tranny out of the MA61 Supras (1982-1986).
 

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i know my program doesn't take into account drag(read the title bar
) however, if you have the power to overcome drag, then it doesn't need to. all those figures assume you can overcome drag with however much HP is needed...so, if you take it to 6600 RPMs in 2nd gear, you should be able to hit the 60 mark...we'll find out once we get in the car though....my program is just an estimator, and doesn't take into account real life situations


auto

vs manual


we dont have the power to hit 164 and proably not even 153, due to drag, etc.

[ August 03, 2001: Message edited by: scoot557 ]
 

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exactly!

Originally posted by scoot557:
however, if you have the power to overcome drag, then it doesn't need to
 

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So does this mean that the RPM in 5th gear of the manual is going to be higher than the auto? I think the RPM in 5th of the auto is too high as it is. I don't understand why they need 5th to be geared so low.
 

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marke1: these are exactly our feelings!!

we will take a chance on getting flamed here by saying that we would buy an IS with taller rear axle gearing, (e.g. 3.0 or 3.2 to 1 ?), if offered as an option...

then again, we're not ten-tenths drivers (undoubtedly we are in the minority of prospective IS owners). Thus, we are looking for a small, tight-handling vehicle with a bit more safety (air bags) and luxury than a mazda protege (wife's current car); very high acceleration is not the highest priority. 0 to 60 times that are 'acceptable' (whatever that means) would be nice, though.

take care!!

:dave and krystyna

[ August 03, 2001: Message edited by: 4krysia ]
 
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