Speed Governor

and its no good for the kids either... errr...i mean transporting the laptop cross cities
i keep my fingers crossed that i will find someone with a riv and a tuner in FL. ill let know know if i do.
anyone know if the DHP PowerTuner will work if its setup for a GTP or the "all" 97-02 bin?

Rhino, what year is your Riv?

it's a 97

only 120mph?
what do i need to do to get rid of the limiter?
like are cars can hit that limiter at the end of the on ramp
lol

Actually I believe the cut-off is 108 mph.

Yes, it's def not 120mph.

First, make sure your tires are rated for the speeds you may travel. That's the big reason for the limiter in the first place, the oem tires are not rated for higher speeds.

Second, you will need either a DHP Powrtuner or HP Tuners tool in order to change this. DHP is discontinued, but used ones can be had for a few hundred. I'm also not sure if HPT supports all the Riv model years, so you'd need to check into it with them.

Or find someone in your area with a tuner who is willing to change it for you. I personally wouldn't do it unless I could SEE the speed rating on your tires.

I hit 120 in my riv on a nice strip of road with little trafic! And I never messed with the tuning. And I'm the 2nd owner of the car the 1st was a older couple and I dought they messed with it.

Bear in mind the speedometers on these cars can be a little innaccurate at those speeds. while 120 would be pretty far off for your speedo , its not impossible. I've heard of a few 95s that weren't governed but i'm pretty sure the rest are limited at 108.

the needle realy went pass 120mph a little! It happend when I went WOT from a 45mph roll.

I remember my first Cadillac was a 96 STS. Z rated with z rated tires. 150MPH limited. I took it up to 145MPH, snapped a pic and MAN was that rush.

1wickedninja wrote:

the needle realy went pass 120mph a little! It happend when I went WOT from a 45mph roll.

Not all needles are calibrated correctly, especially at high speeds. What size tires are you running?

Right now i have Goodyear p225/60r16 they came with the car when i got it. im going this weekend to get new ones. any suggestions?

Those are the correct size. My only suggestion, if you're planning to be hitting the speed governor any more, invest in some W (Z-rated) tires.

I have H rated (for 130mph) BFG traction T/As as do a few others on here and i love them. If you plan on doing very high speeds i'd reccomend getting the V=rated versions , but if you're like me and only plan on going that fast once in a while then H rateds should be fine. These tires hook up off the line incredibly well too.

allright i will look into those thanks guys.

More on tires here:

https://rivperformance.editboard.com/brakes-suspension-f6/performance-tires-t1385.htm

I like the Tractions TA's also, for a moderately priced option.

Boy everyone else doesn't know how good they have it... My frickin' limiter cuts in at 96!! And that's accounting for speedo error.

Why the hell didn't these tire cheapskates/safety dweebs just put an orange band on the speedometer like Ford used to do?

AA wrote:

Some get going down a hill with the wind at their back, and may roll to higher speeds, but the cut-off is 108 mph.

Another big mistake people make (and probably the reason for this whole discussion) is to use their dash speedometer to monitor speed, which is often slightly off, more so the faster you go. For example, mine reads 70 mph when my scanner says 67. My tach is the same way. It's nearly impossible to align the needle and marks exactly during the assembly process.

Doesn't matter how slowly you ease into it, or what gear you're in... when the PCM sees 108, you're getting shut down. And going that fast on stock tires is completely nuts. Two of my OEM Michelins (the good ones) literally tore apart at 80 mph before I replaced the set. Junk tires, imo.

I agree that it's stupid to go that fast on regular tires, but I did have my Fiero pegged at the 0 one time (85GT). Top speed with the auto was supposed to be like 125 or 130 and I was almost redlining it on older S rated tires. Car drove smooth as hell after the 85mph mark. Tires didn't show any signs of stress or wear afterward and I sustained that speed for a good 2 or 3 miles. Would I do it again? probably not. Surprised I didn't see any cops.

mine is set for 115mph

99RivieraLB wrote:

mine is set for 115mph

Has this been verified with GPS? Or, did you reprogram the PCM? The speedometer is not accurate enough to determine where your cut-off is set.

My 97 riviera is limited to 110-115 mph.Is there anything i can do to change this?
My guess is thats in the computer..

Governor is set to the rated limit of the stock S-rated tires.

I have heard of using the Tech II to raise the "governor" limit if higher rated tires are installed. I do not know how.

I think elsewhere on this site someone wrote the calculated top speed of the vehicle in still air on level ground was in excess of 150 mph but I also don't know that, someone please comment who does know.

I've never seen how to change the fuel cut-off with a TechII...I've looked. I do know that the car would prolly hit 150 easy....I've been 140 on the freeway with lots more to go. Was havin fun until I remembered the tire rating

Abaddon wrote:

I've never seen how to change the fuel cut-off with a TechII...I've looked. I do know that the car would prolly hit 150 easy....I've been 140 on the freeway with lots more to go. Was havin fun until I remembered the tire rating

Yeah, I'd hear of resetting the "top speed" but don't know how. Not something I've considered doing. And on a Riv even if you could, would you want to? That car would need some suspension tuning and adequate tires for the speed at least.


Albert