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Unread 06-11-2014, 10:09 AM   #16
IlliniJeeper
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Originally Posted by Wheelin98TJ View Post
The speed limiter is based on speedo reading, not actual speed.

With 3.55s and 33s, you're geared for top speed.

I guarantee that TJ could hit 90 mph.
Yes, that's exactly what I said. With 3.55s and 33s, your issue isn't gearing, it's horsepower. I doubt that 17 year old 4.0 has the guts to hit 80. My 16 year old 4.0 with 33s and 4.56s has issues keeping speed above 80 with any kind of elevation change.

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Unread 06-11-2014, 10:19 AM   #17
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Quote:
Originally Posted by IlliniJeeper View Post
Yes, that's exactly what I said. With 3.55s and 33s, your issue isn't gearing, it's horsepower. I doubt that 17 year old 4.0 has the guts to hit 80. My 16 year old 4.0 with 33s and 4.56s has issues keeping speed above 80 with any kind of elevation change.
Are you driving in 4th or 5th?

I could see it struggling in 5th, but not in 4th.

My friend has a '97 5 speed with 33s and 3.55s and he has no problem running stupid speeds on the highway. I think he is a member here, maybe he'll chime in this thread.
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Unread 06-11-2014, 10:26 AM   #18
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If this is an AX15 with 3.55's and 33" tires, to get to 100 in 4th, the rpm would be 3,615 and in 5th would be 2,855. So, can the Jeep get to 100 with your gearing, absolutely. The question would come down to if the motor can generate torque fast enough to get there (HP). So, your argument would need to be that your engine is worn and cannot generate enough power to turn the motor at 3,615 in 4th or 2,855 in 5th.

I would not recommend using this as an argument to prove you were not going 100.
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Unread 06-11-2014, 10:32 AM   #19
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Quote:
Originally Posted by Wheelin98TJ View Post
The speed limiter is based on speedo reading, not actual speed.

With 3.55s and 33s, you're geared for top speed.

I guarantee that TJ could hit 90 mph.
It says "stock" 3.55 gears with a manual transmission. Let's guess that's correct though...

AX-15, stock np231, 3.55 gears, 32" rubber = 2945 RPMs at 100mph. Quite plausible.

Maybe his profile is wrong...

AX-15, stock np231, 3.07 gears, 32" rubber = 2547 RPMs at 100mph. Doable.

http://www.grimmjeeper.com/gears.html

Quote:
Originally Posted by Wheelin98TJ View Post
no problem running stupid speeds on the highway.
I used to have a 96 Cherokee with the 4.0L, 3.07s, and 32s. Your statement is accurate, brick like aerodynamics and all.

Another thing that seems accurate, is if you're doing 100mph on a public road and the cop drags you from the Jeep and kicks your ***. Police brutality tag might be accurate, and possibly well deserved.
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Unread 06-11-2014, 10:51 AM   #20
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i was pulled over for doing 40 in a 25, it had recently gone from 35 to 25. the cop came flying up behind me and seemed a bit stressed. we talked for a minute and he asked how fast i was going, i said 40, this was a 4 dr stick shift explorer with a v6, not too powerful or fast. he asked me to step out of the car and come with him, i was just happy he didnt slap the cuffs on me at that point. we walked to his car and he showed me the radar, 77mph. i said, "you didnt see my brake lights until you were right on top of me, you would have been doing well over 100 to catch me that fast." he agreed and noticed i lived a few blocks down the street and knew there was no way to get that truck to those speeds and slow down to a reasonable speed in that distance and without using the brakes.

i didnt get a ticket or even a warning, but if he wanted to, he could have taken me to jail and impounded my truck, all due to a faulty speed gun
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Unread 06-11-2014, 11:46 AM   #21
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I'm another with a Garmin GPS, and I make sure the track log is on, so i can prove what my average speed is between any two points of the track (assuming accurate positional data for those two points). As far as speed limiters go, I wonder if we have them programmed over here. The specified top speed for TJ Wranglers in the UK is 108mph.
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Unread 06-11-2014, 12:32 PM   #22
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Start sending certified letters to the department requesting records of the gun's calibration. You won't receive a response, but wait a week or so and send another letter requesting it. Make sure these are all read return receipt (they have to sign to receive the letter, the signed receipt is automatically mailed back to you). Keep copies of these letters.

Go to the court and fight the ticket, if the cop shows up, you request it be dismissed based on the fact you never received a response for your (legal) request for the calibration records of the gun used for recording your speed. You are technically innocent until proven guilty, take aware their defense and you are in the clear.

But if you were going 100mph, slow down dangit
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Unread 06-11-2014, 12:52 PM   #23
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keep us informed on this mess.100 mph is jail ,loss of license and a huge fine here.
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Unread 06-11-2014, 12:55 PM   #24
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The cop will bring in the records of the calibration. Its part of the log he keeps.....

Just start looking up faults they can have. Ghosting,. shadows, refraction, bird flew by, reflector in road.....
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Unread 06-11-2014, 01:08 PM   #25
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In my area you don't get to see a judge or even the cop the first time you are at the courthouse to fight the ticket. You see a magistrate. He, based on evidence the cop sent in (against which you cannot defend yourself because he/she is not there) and your testimony, determines what the fine is going to be (which is typically reduced by some token amount). Then, after having already missed work to attend this bogus magistrate session, if you still want to "fight it" you do not accept the magistrates terms and another date is set for an actual hearing with a judge. Of course by then most folks have lost enough in wages such that it is cheaper to simply pay the ticket.

What a racket.
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Unread 06-11-2014, 01:15 PM   #26
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keep us informed on this mess.100 mph is jail ,loss of license and a huge fine here.
In Texas where he's from it's called driving normal.In Va it's loss of license for 30 days.To the OP,go to court and tell them you didn't know the PO forgot to change the speedo gear for the larger tires.The worst the judge can do in Texas is take you out back and shoot you.
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Unread 06-11-2014, 01:44 PM   #27
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Quote:
Originally Posted by IlliniJeeper View Post
Yes, that's exactly what I said. With 3.55s and 33s, your issue isn't gearing, it's horsepower. I doubt that 17 year old 4.0 has the guts to hit 80. My 16 year old 4.0 with 33s and 4.56s has issues keeping speed above 80 with any kind of elevation change.
for argument sake, my 17 yr old 6cyl tj with 35's and 4.88's can hit 80 on a slight upgrade.... Im at sea-level but still..... It's called maintenance...
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Unread 06-11-2014, 02:17 PM   #28
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Originally Posted by brokenyoujoint View Post
for argument sake, my 17 yr old 6cyl tj with 35's and 4.88's can hit 80 on a slight upgrade.... Im at sea-level but still..... It's called maintenance...
Around here, the elevation changes I'm talking about necessitate truck lanes. I take issue with the implication that I've neglected maintenance on my rig.
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Unread 06-11-2014, 02:23 PM   #29
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Originally Posted by Wheelin98TJ View Post
Are you driving in 4th or 5th?

I could see it struggling in 5th, but not in 4th.

My friend has a '97 5 speed with 33s and 3.55s and he has no problem running stupid speeds on the highway. I think he is a member here, maybe he'll chime in this thread.
Yes, I'm talking 5th gear. If you're shifting down into 4th to build up speed, you kind of have to know that you're flogging it between the actual need to down shift and the racket that the drivetrain will be making. Hard to make the argument that you were just cruising along and "accidentally" got to 90+ mph in 5th.
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Unread 06-11-2014, 02:28 PM   #30
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Originally Posted by AWheeler View Post
If this is an AX15 with 3.55's and 33" tires, to get to 100 in 4th, the rpm would be 3,615 and in 5th would be 2,855. So, can the Jeep get to 100 with your gearing, absolutely. The question would come down to if the motor can generate torque fast enough to get there (HP). So, your argument would need to be that your engine is worn and cannot generate enough power to turn the motor at 3,615 in 4th or 2,855 in 5th.

I would not recommend using this as an argument to prove you were not going 100.
-------
Agreed, And the cop will say you were runnin" downhill with tailwind. Your only hope is proving the equipment the cop was using was faulty!
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