Novak Conversions Jeep Wrangler TJ radiator

100 mph in a TJ; have you done it?

My 05 LJR is speed limited by the PCM. It stops going faster around 95 mph. So did earlier model PCMs allow higher speeds?

It's impossible to go 100mph in my 05 because of the PCM.
 
I’m also a pilot and density altitude does not only effect power production, but also wind resistance, or as we call it, drag.

A Jeep has an aerodynamic coefficient similar to that of a brick.
 
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I did it once. Once. Indicated, not GPS, but my speedo is spot on at lower speeds, with 235 tires, so I think it was a real 100mph.

6cyl, 5 speed, ‘97, bone stock.

Engine and drive train were loafing, it’s a tall 5th gear. Hard top was on.

I would describe the overall feel as “mildly terrifying.” I didn’t feel like I was just about to crash and burn, but rather it was a definite possibility. My TJ cruises comfortably at 85, so it wasn’t all that much faster, but I’ll never do it again. Just wanted to see if it could.

I feel like I probably would have topped out around 110-115 drag limited, but the speedo doesn’t go that high anyway.

Has anyone gone faster?

R805f968a9578e758c5943f9e92911a07.jpeg
 
My 05 LJR is speed limited by the PCM. It stops going faster around 95 mph. So did earlier model PCMs allow higher speeds?

It's impossible to go 100mph in my 05 because of the PCM.

It's possible if you don't let the PCM know the right speed, apparently!
 
Uh, no.
I did hit 80 mph once on the interstate where the speed limit is 70 mph. It felt great...as long as the road was smooth. Any road imperfections and all bets were off.

I have absolutely no desire to do so, but if I had a smooth road I believe I could reach 42 mpg...ERR, I MEAN 100 MPH!!!

(I sort of miss those threads) Lol

Disclaimer:
I am including a pic for (sort of) proof of my 80 mph...and to prove that I didn't do the math in my head, nor am I asking anybody to show me their math, proving how they achieved 100 mph.
20250524_164148.jpg

And yes, it's in portrait mode.
 
I've briefly been up to the low 80s in the Benz a time or two - although that car will go faster, blah, blah. The fastest I've ever driven in any vehicle was - wait for it - 88 MPH! In an '88 Ford Tempo on a back ag road. Unlike the Benz, the Tempo felt like it was going to shake apart!

As for the Jeep, I had it up to 75 once when I was calibrating the speedo, otherwise the fastest is 70, although I really don't like going that fast.
 
I've briefly been up to the low 80s in the Benz a time or two - although that car will go faster, blah, blah. The fastest I've ever driven in any vehicle was - wait for it - 88 MPH! In an '88 Ford Tempo on a back ag road. Unlike the Benz, the Tempo felt like it was going to shake apart!

As for the Jeep, I had it up to 75 once when I was calibrating the speedo, otherwise the fastest is 70, although I really don't like going that fast.

My brother bought a SRT-10 truck and got it up to 142 mph on the drive home. I just wondered why? Not a way I want to die. :unsure:
1748164718098.png
 
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The time: 1982

The place: small town Pennsylvania

The thing: 1970 Pontiac Firebird Formula

The driver: my idiot friend

The age: 16

The weed: some kind of nasty brown shit with mandatory exploding seeds

The speed from Burger King to the next light about 2 miles away: 135mph

The beer: probably Strohs but I was stoned so who can say for sure

strohs.jpg
 
I got a ticket for doing 87 in mine, he bumped it down so it wasn't a super speeder. It was on a downhill, I was actually trying to see how fast it would go lol, just my luck there was a cop at the bottom of the hill.

I didn't figure out the top speed, but I did figure out that over 75mph the steering feel goes from okay to oh shit 🤣
 
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My 2001 Ford Lightning was clocked at 167mph on Route 65 just East of Covington Virginia.

My 2006 TJ was clocked at 75mph one time, which is absolutely fast enough for me.
 
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Novak Conversions Jeep Wrangler TJ radiator