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Discussion Starter · #1 ·
ok, now break out your calculator....here´s how it goes

speed(MPH) = (RPM x tire diameter) / (gear ratio x 336)

I did not know the gear ratio so I used the following formula to find it.

Gear Ratio = (RPM x tire diameter) / (mph x 336)

I got these formulas from:PreStage.com Car Math Formulas

Gear Ratio = (RPM x tire diameter) / (mph x 336)
Gear Ratio = (3000 x 22.6) / (60 X 336)
Gear Ratio = (67800) / (20160)
Gear Ratio = 3.36

3000 being the rpms shown on my gauge at 60 Mph
19 being the overall diameter of the wheel and tire together....15 inch wheel with 4 inches of total sidewall(counting both sides together)

Speed (MPH) = (RPM x tire diameter) / (gear ratio x 336)
Speed (MPH) = (7000 x 22.6) / (3.36 x 336)
Speed (MPH) = (158,200) / (1128.96)
Speed (MPH) = 140.1289683 MPH

There is the math, I used the actual measurements from my car and figured it out....now I want to hear comments on my estimation of my speed made in an earlier post. I know that I will hear people saying I should not drive my car at the redline...but it´s my car and my decision. I based my original estimation on that when my car turns 3000 rpms at 60 mph and 4000 rpms at 80 mph, when my car was turning 7000 rpms and my speedo was down near the trip meter it was an easy estimation of 140 mph. I had figured that when I did the math I would come up around 2 mph or so off so this was a bit closer than I had even thought. I hope this clarifies things for the young ignorant people who think that just because they haven´t done it or that because the speedo reads only a certain speed that the car cannot outperform the norm. I would also like to state at this time that when I did this my car was not bone stock, I have never said it was, I have not done what I would consider any major work to the car though and if you would like a rundown of what I have done to it feel free to visit my page.

Mike´s GT

Livin la vida Escort

[ This message was edited by: 93EGTinLR on 07-04-2003 06:52 ]
 

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Gear ratio´s for the 91-96 GT and the 97 SE are as follows:
1st 3.30:1
2nd 1.83:1
3rd 1.31:1
4th 1.03:1
5th 0.79:1

So you don´t have to do all that extra math, unless you really want to. ;-)
 

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Discussion Starter · #3 ·
well the reason I did the math was to figure in everything from the tranny and the tire sizes...it actually simplified things for me...no half guessing about the final drive ratio....I wanted to be as clear as possible
 

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Oh yeah, here´s where Brian found the tranny specs for me.

Transmission Specs

So that´s to combat ProudEGT who, like with everything else, will be thinking I´m just lying my ass off about the gear ratios. Anyway, I never doubted you myself because I´m sure I could hit 125+ if I had a straight enough highway to play on without getting caught. It´s been too long since I´ve been in school and I started to actually like math my latter years in high school. Thanks for making me think. lol ;-)
 

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Discussion Starter · #6 ·
that´´s ok, 92gt5sp has been calling me a liar and a fuck and I just had to do the math...whether or not it worked out for me or not. as for the ratio, I´m not sure if you would call it the final drive for all gt´s as I run a different tire size..but that would be the drive ratio for mine....according to the formula I had access to....it´s been a few years myself for the math...only been out of high school for 13 years and some....I appreciate that you never doubted me, and I wanted to set it as straight as I could...no doubt someone is going to still say I am full of shit...but someone mentioned to do the math that it would not work out...well I did the math....lol....hell I even tried to squash it since I saw no real need for a flame war either...but it came up again...so here it is...I think me and my friends who were trying to keep up in their scorts...2 3gen sedans a 2 gen 1.9 and a zx2...were very lucky not to run across the law....I thank my lucky stars for that...we all would have been in jail for sure
 

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Yeah I know. he´s from Ohio though, so yeah. hehe ;-)
Just prove your point, which you did, and whatever crap he wants to throw at ya just ignore it. :cool:
 

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WTF 15" size are you using that´s ONLY 19" OD?!?!?!?
a 195/50r15 would be appx 22.6" OD
my 205/50r15 is appx 23"

a 15" with 4" of overall sidewall would have to be a non-existent size
195/25=18.84"
195/30=19.61"
205/25=19.04"
 

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I came to the same conclusion when I had my 94.The speedo stops at 125 but I know I was doing way faster then that.I used to say 140 but some people didn´t believe me either until I took a few for a ride.Just bite the bullet and say 138 People don´t want to believe an escort is capable of 140.Especially with so many stock Hondas limited to like 117.I used to look for em because I knew on the freeway they were an easy kill.
 

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Discussion Starter · #14 ·
<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%>[TR][TD]Quote:

[/TD][/TR][TR][TD]
06-04-2003 at 22:25, bpletch1 wrote:
WTF 15" size are you using that´s ONLY 19" OD?!?!?!?
a 195/50r15 would be appx 22.6" OD
my 205/50r15 is appx 23"

a 15" with 4" of overall sidewall would have to be a non-existent size
195/25=18.84"
195/30=19.61"
205/25=19.04"
[/TD][/TR][TR][TD]

[/TD][/TR][/TABLE]

ok, maybe I measured wrong....so check it out I redid the math and it came out even more ....lol
 

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<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%>[TR][TD]Quote:

[/TD][/TR][TR][TD]
07-04-2003 at 02:38, PTMD wrote:
I used to say 140 but some people didn´t believe me either until I took a few for a ride.Just bite the bullet and say 138 People don´t want to believe an escort is capable of 140.
[/TD][/TR][TR][TD]

[/TD][/TR][/TABLE]

I got my wagon to do 119 :-]
 

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Discussion Starter · #16 ·
funny to me, after what went on in another post about top speeds I figured this one would get alot more responses.... :-o
 

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I decided to go and argue in 3 other forums instead. lol :-]

Hey I got the money order for ya. I got it for $65.00 even so I didn´t have to mess with the change. All I gotta do is sign it and it´ll be in the mail tomorrow man. ;-)
 
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