I just bought a 2001 Z28 in Arizona yesterday and when it hits 115 the car strarts to shake and it won't go past that. I tried it in both 5th and 6th gear? If its the governor how do I remove it?

 

Well I don't know about shaking, but I know my 2001 camaro ss has a speed limiter programmed into the computer somewhere around the speed you are talking about. By the way, what is the reason you need to go that fast.

 

That is the speed limiter. You have to change the tune in order to modify or remove it.
It shakes b/c they cut timing/fuel (I don't remember which).

 

Now that's a silly question!!

 

Look at the tire info on the door jamb, if it didn't come with Z rated tires you get the lower speed limiter. Easily removed by tuning software, even most hand helds let you do it.

 

That would suck...

 

Your tires probably need to be rebalanced. At that speed even tires slightly out of balance, the vibration is magnafied many times. One way to remove your speed limiter is to send your PCM into www.pcmforless.com

 

Seems like it would not be expensive just to tune out the speed limiter.
Who needs to go that fast. Geez, get a Mustang.
If someone could post the RPO code, you could verify, but that is the exact speed of the limiter, so...

 

It is the speed limiter cutting in. Your car probably came with the B F Goodrich cheepie tires when it left the factrory. So it had the speed limiter because you did not have Z rated tires on the car as orginal equipment. You can have it tuned out of your PCM. I know because my car was the same way. 118 MPH was as fast as it would go. Needless to say I tuned it out years ago.

 

If it's the governor, "shake" isn't how I'd describe it. When the car hits the governor, power just abruptly cuts off and the car coasts until it drops 2-3mph from the limit, at which point it will accelerate to 115 again. It will repeat like that for as long as you hold the pedal, and the cycle takes about 2 seconds.

If that sounds like what you're experiencing, then you can have the governor "tuned out" with a mail-order tune, which will cost you roughly $150.

If it's something different (a more violent shake), then go to your favorite tire shop and ask them to re-balance the tires. If that still doesn't fix it, come back and let us know.

 

I am not a fan of Hypertech, but their handheld will tune that out and you won't have to send off your PCM. They sell used all the time.
$150 seems like a lot of cash just to change one parameter.

 

Search user name "FROST" on LS1tech.com
$125 mail order tunes and he's very good and he'll take care of your limiter plus give you more power in the process. Your welcome

 

as stated above . if the car didn't come with "Z" rated tires the speed limiter was set at 115 MPH with i belive it was set at 155 MPH with the Z rated tires . iv'e reached 145 easly @ 4500 RPM. check the tire option list with the 245/50 ZR 16 tires at an additional 225 dolllars (2001 Z28)

 

I have z-rated tires on my 2001 ss ( 275/40/ZR17 ) and the speed limiter is programmed at 126mph from the factory. This is what the dealer said the car was set to when I bougth it new. I've never tested it so I can't be for sure.

 

When you bought the car new, did it come with Z rated tires? If it did, it shouldn't have a speed limiter.