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Discussion Starter #1
If our car is only limited to 140 (estimate), if we throw in a turbo kit, how does it work?

Do the people that install the kit, remove it or ???
 

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HoustonLex said:
redline in 5th gear is 143mph... putting a turbo kit on only makes you get there faster... you still run out of gear
sorry but that is wrong :shame: GTE can chime in if he would like but you will only be able to go faster with a stand alone EMU most Turbo kit come with a piggy back. so you have no control over this aspect of the car :chill:
 

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GTE can chime in if he wants, but Ive redlined the car in 5th... shes got no more gear... now, put in the 6th speed (ala GTE), and you have a totally different story...
 

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BugginOuT said:
but with a Turbo Kit, are u still limited to that 143mph?
Do you understand the basic premise of gear ratio's???? I dont care if you have a billion zillion horsepower, if the car runs out of gear, meaning it is redlined in high gear, all that extra HP will go to waste...
 

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Discussion Starter #7
HoustonLex said:
BugginOuT said:
but with a Turbo Kit, are u still limited to that 143mph?
Do you understand the basic premise of gear ratio's???? I dont care if you have a billion zillion horsepower, if the car runs out of gear, meaning it is redlined in high gear, all that extra HP will go to waste...
Of course, i don't understand, why da hell do u dink i'm asking! :bitching:

But thanx for pointing it out.

I learn something new everyday. :wink:
 

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HoustonLex said:
GTE can chime in if he wants, but Ive redlined the car in 5th... shes got no more gear... now, put in the 6th speed (ala GTE), and you have a totally different story...
:lol: :lol: sorry but I have had the car in 5th gear with cruse set at 143 ( actually 145 on the speedo and still had 500 rpm to go before red line but the car shut down if you would try and go any faster and there was still plenty of power to go faster

:eek: :eek: may be some one changed your gears :eek: :eek:
 

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mathematically if you calculate the maximum speed, the car will go 148mph....

I consider that negligible... carry on...


my point is still valid, a turbo will not make you go any faster due to gear ratio's
 

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HoustonLex said:
GTE can chime in if he wants, but Ive redlined the car in 5th... shes got no more gear... now, put in the 6th speed (ala GTE), and you have a totally different story...
well her is what I have been able to find with a very simple search.

IS300GTE said:
some of the gears are actually shorter, and when used with the stock rear, you would be shifting too much, it would be annoying as hell
you'd be shifting into 5th gear, for anything much faster than stock


2002 stick gearing
Gear Ratios
1 : 3.566:1
2 : 2.056:1
3 : 1.384:1
4 : 1.000:1
5 : 0.850:1
Final drive : 3.727:1


2002 auto gearing
Gear Ratios
1 : 3.36
2 : 2.18
3 : 1.42
4 : 1.00
5 : 0.75:1
Final drive : 3.90:1


supra six speed gearing
Gear Ratios
1 : 3.830
2 : 2.360
3 : 1.690
4 : 1.310
5 : 1.000
6 : 0.790
Final drive : 3.130
http://www.is300.net/forum/viewtopic.php?t=13335778&highlight=speed

and from this link

http://www.is300.net/forum/viewtopic.php?t=13332958&highlight=speed

IS300GTE said:
by the way, the top speed of the manual IS is 165 (approximately - i forget my exact number that i calculated) without the limiter, and not much different with the 6 speed ... why, because of the 3.729 rear end.

i don't think you know what is involved in swapping the tran's, and what it takes to beat the speed limiter and ecu, or how much $$$ is required to do such

if you are still hell bent on knowing the difference, i will calculate the differences in top speed, later today

-gte
so I don't know you can make your own call BugginOuT but I know what I know from my own experiances :chill:
 

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HoustonLex said:
mathematically if you calculate the maximum speed, the car will go 148mph....

I consider that negligible... carry on...


my point is still valid, a turbo will not make you go any faster due to gear ratio's
want to check your math ?
 

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HoustonLex said:
mathematically if you calculate the maximum speed, the car will go 148mph....

I consider that negligible... carry on...


my point is still valid, a turbo will not make you go any faster due to gear ratio's
want to check your math ?
 

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Sure, Im sick of hearing, GTE said this, GTE said that... its all a bunch of 16 year olds quoting what their dad said...

MPH = (RPM * Tire Diameter (inches)) / (Gear ratio * 336)

If you want me to derive that formula, PM me....

Assumtions: Redline = 6250rpm Tire diameter of stock setup = 24.6 inches Gear ratios, Im using the ones from the quote above


Gear ratio in 5th gear = .850 * 3.727 = 3.16795

MPH = (6250 * 24.6) / (3.16795 * 336) = 144.44

Originally I said 148 because that was using different gear ratios. Since someone found what I assume to be correct ratio's, I decided to use them instead.

From now on instead of quoting others comments, how bout figuring it out for yourself....
 

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HoustonLex is CORRECT. Most people who think different have just read other incorrect posts and/or havn't actually tried maxing out 5th gear.

I held the 143 mph for around 15 seconds and it was at redline...MAYBE 100 rpms left. But if there was a speed limiter and you took it out, you'd just start bouncing off the rev limiter at maybe 146 mph (or whatever math you have to do to calculate)...
 

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lil' IS 300 said:
HoustonLex is CORRECT. Most people who think different have just read other incorrect posts and/or havn't actually tried maxing out 5th gear.

I held the 143 mph for around 15 seconds and it was at redline...MAYBE 100 rpms left. But if there was a speed limiter and you took it out, you'd just start bouncing off the rev limiter at maybe 146 mph (or whatever math you have to do to calculate)...
Well I have and im sure TicalIS300 (aka Lexotic Concepts), and CruznIS300, and a handful of others who have hit the 143 top speed locally on our previous CT meets can attest that they hit the 143mph mark before they hit redline by far. I know I have hit 143-144 before my car has (1) hit redline (2) run out of gearing. So I dunno bout the rest of you guys.
 

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When I was on the SRT piggy with Stage 4 turbo, I easily hit my 143mph speed governor, BUT did not hit the rev. limiter. I still had more on the rpm to go. Ofcourse with a standalone all this is null & void to a point.
 

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HoustonLex said:
Sure, Im sick of hearing, GTE said this, GTE said that... its all a bunch of 16 year olds quoting what their dad said...

MPH = (RPM * Tire Diameter (inches)) / (Gear ratio * 336)

If you want me to derive that formula, PM me....

Assumtions: Redline = 6250rpm Tire diameter of stock setup = 24.6 inches Gear ratios, Im using the ones from the quote above


Gear ratio in 5th gear = .850 * 3.727 = 3.16795

MPH = (6250 * 24.6) / (3.16795 * 336) = 144.44

Originally I said 148 because that was using different gear ratios. Since someone found what I assume to be correct ratio's, I decided to use them instead.

From now on instead of quoting others comments, how bout figuring it out for yourself....
Before you get your internet mussels all in a bunch you should know who you are talking to.

so to help you out I took the time to do the math my self.

as our cars are rear wheel drive wheel diamater does play a large part in top speed. I own a 2001 auto sorry I could not find the exact gear ratios for a 2001 so I will use the ratio for a 2002 if that is ok.

sence I know you know the forumla I will just post the numbers.
2454018
(6250 * 25.7) / (2.925 * 336) = 163.4361

the car will not let you get that far in the RPM band.

in 5th gear with my set-up

(5500 * 25.7) / (2.925 * 336) = 143.82372

now I still have 1000 Rpms that I can not use can you please explain how I am geared out :-? and the car will let you set the cruse at 5250

sorry but I have had the car in 5th gear with cruse set at 143 ( actually 145 on the speedo and still had 500 rpm to go before red line but the car shut down if you would try and go any faster and there was still plenty of power to go faster
so I will retract the statment I made above as I could have been wrong but when you are traveling at that speed for any amount of time you are not driving with one hand on the wheel and one out the window. I am not looking to start a flame war here but if you are ever in my town I would be more then happy to take you for a ride :chill:

I edited it for a typing error and a quto that was wrong
 

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*banging head on monitor*

So what have you proven? That by changing the gear ratio (via tire diameter), you effectively change the theoretical top speed?

Thanks sherlock... I would have never imagined that would be possible :roll:
 
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