Mariusz

I was just curious how the GS400's gear ratio would compare against TT Supra's #'s. Assume the drag coefficient is the same and don't take into consideration anything else for now. Who would have the advantage on the highway and why (I'm in the dark in regards to this area)? What would be the optimal gear for me to run at? I also have the TRD LSD. Also asume stock wheel size. How about with 20's?

Just doing my homework


--------------Supra TT (6Spd)------------GS400----

1st ---------- 3.827 / 3.724 --------?
2nd --------- 2.360 / 2.246 --------?
3rd ---------- 1.685 / 1.541 --------?
4th ---------- 1.312 / 1.205 --------?
5th ---------- 1.000 / 1.0000 -------?
6th ---------- .793 / 0.818 ----------?
Final -------- 3.266 -------------------?

Mr Johnson

Gear Ratios:
1st
3.357

2nd
2.180

3rd
1.424

4th
1.000

5th
0.753

Reverse
3.431

Final Drive
3.266 (GS4x0)
3.916 (GS300)

GS400_PUSHER

Hey man If you are racing the same dude with the white Supra my money is on you but I bet he is gonna get alot more stuf done because he knows you are comming for him!!!!! Just make sure you video this one TOO!!!!!!!

Mariusz

--------------Supra TT (6Spd)------------GS400----

1st ---------- 3.827 / 3.724 --------3.357
2nd --------- 2.360 / 2.246 --------2.180
3rd ---------- 1.685 / 1.541 --------1.424
4th ---------- 1.312 / 1.205 --------1.000
5th ---------- 1.000 / 1.0000 -------0.753
6th ---------- .793 / 0.818 -----------------
Final -------- 3.266 -------------------3.266

Thanks Mr. Johnson. Now, how do I interpret these figures for a highway run?


Actually you are absolutely right. Lol. He went single (T61) since he knew the Lex was coming. Now, I will end up racing a single Supra! You might reconsider your bet. Lol. I'm just doing some homework so that I can see how much more HP I'm going to need in excess of 500RWHP.....or how big the blue bottle will have to be. Win or loose, I think it will be impressive to see a luxury 4 door go against one of the fastest cars on the road today. You lnow I always record my runs, so expect to see a nice video.

Richie

Really looking foreward to that vid!!!!!

ShowGSLuVv

hey Mariusz, u got any Video's of ur car that I could check out, I been searchin all over and can't seem to find any of ur GS after the Twin turbos, I remember someone sayin that there is a recording of the car when u guys were doing a Dyno, anyone have it so they can post it up? thanks

ShOwGS

Mariusz

That is becasue all the videos I have, were made before the TT setup and since I don't have my car back yet (3 more weeks) I haven't had a chance to make any more videos videos Once I get my car back, I'll post the old and the new ones there. Stay tuned

LexCiting

What you up to?????? LOL

JBrady

To compare you multiply the tranny gear x the diff gear x torque (average over the used range)

You then divide the weight by this number to find out your lbs vs torque ratio per gear.

example:
GS: 3.357(1st gear) x 3.724(RMM LSD) x 500rwtq(estimated average) = 6250 rwtq... 6250 / 4000lbs (vehicle weight) = 1.56 pounds of force to accelerate per pound of vechicle in 1st gear (the bigger the number the better).

Supra: 3.827 x 3.26 x 500rwtq (estimated average) = 6238 / 3800(estimated vehicle weight with driver) = 1.64 (advantage Supra in this estimate) both cars have MORE than enough force to lift the front tires off the ground provided they could get traction.

Do this for whatever gear(s) you will be running in. Obviously, the actual numbers must be known to accurately estimate any advantage and variables such as driver skill, response, traction, etc all come into play. Exercises such as these are most useful when trying to figure out WHY one car beat another that had MORE power.

Using the above numbers... 4th gear looks like this:
GS: 1.00 x 3.724 x 500 = 1862 / 4000 = 0.466
Supra: 1.00 x 3.26 x 500 = 1625 / 3800 = 0.428
Advantage GS!!!

Now, the Supra MAY have different gears, more or less power, more or less weight... the GS may have more power , less weight...

So, my suggestion... put on a REAL exhaust... run 15psi... make 600rwhp and 600rwtq... and post the videos

kensttgs400

Hey ther Mariusz,

Man this is getting interesting fast!! Can't wait to see how strong your car is. What are the differences/major upgrades over Lexciting's already one of a kind TT. I hate to admit it but I'm going to have to settle for last place in the Twin Turbo war of the GS400's!!

Mariusz

There is no last place with the TT setup Strap on that intercooler, add on the little things here and there and then let her boost. I know Mo will take care of you. I'm not going to discuss the details on my ride untill I have the dyno on hand. Not trying to be "ghey" or anything, but would like to see how it turns out. Besides, I'm in NJ so you guys probably already know much more than me.

PS. The thing with the bottle is a joke for now. However, after I see the figures Mo and I agreed on, I will be talking to him about further development of the TT's potential.

Mariusz

jbrady, much thanks man. Can't believe i missed your post. Went back to see if anyone responded and saw it now. 600RWHP would be nice....wouldn't it? As soon as I get used to 500rwhp+, I can almost guarantee you that you will see a 600rwhp+ GS with no nos! :eek: But I'm going to keep my mouth shut untill it happens. No point in bragging about HP figures if you don't have them Also, I'm thinking twice now why I got that 3.26 gearing. Anyways, it might look different in practice so we'll see.


PS. How would I estimate the average torque quickly and easily? Does the diameter of the wheel matter? Sorry for these dumb questions, but I rather ask then guess.

GS400_PUSHER

Oh yeah !!!!!!

Mariusz

How does the diameter effect the outcome?


jbrady, isn't 4th gear in your example supposed to be:

Supra: 1.312 x 3.26 x 500 = 2139 / 3800 = 0.563

instead of:

Supra: 1.00 x 3.26 x 500 = 1625 / 3800 = 0.428

Advantage to the Supra instead of the GS



Here is a little proggie I made (in C++) to calculate these ratios based on what you said. (Don't bash me on the size or the optimizations...lol....this was on the fly.) It kind of really makes me think about the 3.76 instead of the 3.26 for highway runs (won't need that advantage in 1st or 2nd as I will be smoking the tires anyhow)

For the first time I can see why 3.76 is actually a better choice for a high HP Lexus and 3.26 for a stock GS.

49K Zipped -> http://www.lexushp.com/gear.zip


Supra------GS400
3800lbs----3800lbs
500rwtq----500rwtq
3.266------3.76 (RMM LSD)
-----------------------
0.373---0.213
1.014---1.079
0.724---0.705
0.564---0.495
0.430---0.373


Supra------GS400
3800lbs----3800lbs
500rwtq----500rwtq
3.266------3.266 (Stock LSD)
-----------------------
0.373---0.185
1.014---0.937
0.724---0.612
0.564---0.430
0.430---0.324


PS. Also, which set of gear values should I be comparing for the supra. The ones to the left or to the right? Why?