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Discussion Starter #1
Just wanted to clear up something that is the topic of a lot of posts... The top speed on the '04 GTO is 160mph. Last night the speed limiter was kicking in at exactly 160mph, it felt like I had just hit a ton of bricks when it kicked in, and it doesn't take long to bounce right back to 160!

Now, just need to find a way to take off the limiter and find the true potential!
 

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Are you sure it is a speed limiter? People used to think that the Z28s had a limiter but it was only the cars that were not delivered with Z-rated tires from the factory (115 mph). It turned out that the "limiter" was the electronic ignition turning off because the engine had reached red-line in 5th gear (172 mph). The Z28 would not pull 6th gear at that speed. A couple of military guys stationed in Germany figured this out on the Autobahn. The GTO is geared a bit lower than the Camaros LS1s so this may be what is happening in your case.

I wouldn't encourage anyone to test this out on the GTO. Beware, at 120+ it takes forever to stop and the '04 GTO's brakes aren't its strongest suit.
 

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Whiteshadow said:
Just wanted to clear up something that is the topic of a lot of posts... The top speed on the '04 GTO is 160mph. Last night the speed limiter was kicking in at exactly 160mph, it felt like I had just hit a ton of bricks when it kicked in, and it doesn't take long to bounce right back to 160!

Now, just need to find a way to take off the limiter and find the true potential!
how meny R's were u turnin at 160?
 

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I checked it coming home today. 160 is redline in 5th. No I did not go that fast but 2,000 rpm is 53, 4,000 is 106, thus 6,000 is 160. I haven't read anywhere or in any report that the GTO has a speed limiter. I think this most likely is the electronic ignition turning off at redline.
 

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You be a crazy man! What if a tire blew or a deer ran out? I've been up to 132 in my vette and I saw God.
You be a crazy man-don't do that again!
 

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Saw another post with a guy doing 162 in 6th gear and claimed the speed limter turned off the engine, an indication that this car will hold or pull 6th gear (LS1 Camaro Z28 could not) and if the ignition cut off in 5th doesn't stop you the speed limiter will.

Hopefully, the common sense limiter will kick-in before all this. It is so easy to run this car into the 3 digits - I've just set my overspeed tone at 100 and use at as a knock-it off alert.
 

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wondered where it was...I hit 147 on the third day out...was in the shop getting the graphics on and the man asked me if it had some snap, so I felt obliged to let him know, then he told me he was an Iowa State Trooper...niiiiiiiiiice ;)
 

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That overspeed warning is annoying, I have mine set at 130, 100 mph comes up so fast in this car, and it doesn't take much longer to get to that point, to date I've only had mine up to 126mph. Did that yesterday. It is so smooth you barely notice. I blow by everyone anyways, I just do it quicker with my GTO than with my Dmax.

If you have a class D license, you'll just get hit with a big fine if you do that out of state. Hopefully the state that you get caught in doesn't have reciprocity with your home state. Otherwise you are screwed. I had a friend that got hit with a $600 speeding ticket in VA for doing 120 in a 65 and he was from Washington. Guess he was in a hurry or something.

But if you have a class A then you gotta be on your toes. Or keep your foot out of it, that's the hard part, haha.
 

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:agree That ospeed does come on too fast, and it is really annoying. Mine came on constantly during the test drive, it was on 55 and I thought that was a permanent setting?! I quickly found out how to change it up, but it is handy bc the acceleration is so smooth...you get there in a hurry!
Enjoy your GTO rides today, mine is in the garage under a foot of new IOWA snow. Guess the 02 Avalanche gets the ride today! :D
 

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Discussion Starter #17
Ok, to clear up some more of the things said in the post soo far:

1. Yes, it was a really stupid thing to be driving that fast, and I don't really know why I did, but it's kind of a thing that I do with every vehicle I own. hehe, I topped out my GSXR1000 motorcycle this summer, well into the 190's.

2. I believe I was in sixth gear, and don't know the rpm I was at. BUT I can tell you this... There is for SURE a governor set in the car at 160mph. I had the digital speedometer showing 160mph, as well as the needle pointed at 160mph, when it would back me down roughly 5-10mph. It was startling to say the least, the car pulls pretty damn hard all the way to 160, and running into that limiter really caught me off guard.

3. I know that the C5's are unlimited, and my roomate and I put his up to 175mph, and I believe there was still plenty of power to go further. REASON I mention this, is because I know the GTO can go much faster, it has plenty of RPM's left on the tach, as well as the power to keep going. (not that anyone WOULD or SHOULD.)

4. For the guy asking where I did this, I was right outside of Ames, Iowa... Highway 30 was re-paved this summer from Nevada to Ames, and I used most of that stretch to test the 160mph theory.

5. Someone else mentioned the tire rating. Don't quote me on this, but the BFG's are W-rated, is that correct? And I believe W-rating is limited to 160mph which could be the reason the computers won't let us go any faster. As I understand it, a tire manufacturer is not responsible for any tire failure if the user is operating at a speed higher than the tire is rated? I remember seeing something about this a long while back somewhere, anyone care to add to this?


Anyways, I don't plan on going any faster than 160mph. If I want to go faster, I'll just buy another bike. That way I KNOW if I hit something at that speed, I won't be a vegetable for the rest of my life.
 

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I hit 155 in my 98 LS1 TA Vert (A4, 2.73 rear) two times. Once with the top up and once with it down. The LS1 will pull you to 160 without even sweating. Also, don't forget that your speedo isn't the most accurate device. They can be off anywhere from 3 - 6%.

I got my GTO last night, and haven't taken it over 80 yet, but it was raining. I imagine 160 would be quite a nice ride in this car. It sure is firmer than my drop top was (duh).
 

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Whiteshadow,

You have the BFG G-Force KDWS tires right? Those are ZR speed rated... 201+MPH, fat chance that we're going to get that fast soon. :cool
 

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Actually:

P - 93 Mph
Q - 99 Mph
S - 112 Mph
T - 118 Mph
U - 124 Mph
H - 130 Mph
V - 149 Mph
W - 168 Mph
Y - 186 Mph
Z - 149+ Mph
 
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