I was on I-64 yesterday I decided to bust the 'ol Z28's *** and see just how fast it would go......

At 110 mph everthing is as smooth as silk, but at 115 mph it starts jerking and I think it kicks into nuetral because the tach jumps from about 3500 (approximation, not exact) to like 5000 rpm. I have an A4 and I believe it's governed at 115 mph.

Does this sound at all right?

If not what else could this be? I never heard of a governer this low and especially on a "Z" I thought if they where governed at all it was like at 136 mph.

Help me out.

Jay-mak.

 

don't know about A4s but with my M6 I did 120 easy. I would assume that if they had goveners on them they would have them on both A4 and M6. If you do have some type of speed limiter, you might be able to change it with a programer. ($200-$300) Haven't reached a top speed limiter yet in mine. Good Luck!

 

If whoever ordered the car didn't opt for the z-rated tires then it got a 115ish limiter/governor. As said above, a programmer (HPP, Predator, etc...) will allow you to get rid of it or if you have a shop near you that does tuning, they should be able to help you out.

 

Like it was just mentioned, "factory Z-rated tires" will determine whether your car is governed at ~115 mph, or at ~165 mph (which is a little tougher to reach than 115!!). Obviously your car was ordered without Z-rated tires. Any programmer can change this for you though, whether you get a Hypertech and do it yourself, or have a shop with LS1 Edit or something like that program it for you.

 

How do I find out if my car was ordered with "Z" rated tires or not? Is there a code?

And, is that really the governed limits for the two types of cars (115mph and 165mph)? Have you ever heard of this before with other Z28's?

Jay-mak

 

This is nothing new with the cars. The speed liimiter is on cars that came out of the factory without Z rated tires. Your car should also have a speedo that only goes up to 120 or so I believe instead of the 150-155 that the other cars do. I am sure there is some way to find out from the build sheet or the RPO codes if your car came with z rated tires on not. I just cant help you with that. Probably easiest to just take it to someone and have them remove the speed liimiter. You may even be able to get the dealer to do it for you if you have z-rated tires on the car now. Plus wouldn't hurt if you had a good report with them also.

 

My factory sport appearance package included 235/55/16 wheels on chrome wheels. These are not Z-rated. I found out on the dyno, as well as racing (ie, losing ) on the way back home.

The non-governed speed is ~160 I believe. You could look at the inner driver door panel to see which size tires came from the factory.

 

The 162 speed is also governed. With editing that can also be removed completely

 

i must have been mistaken b4 about my car not having a speed limiter, because tonight i found that past 115 my car jerks backward to 110 like his. Guess I will have to get a programmer to remove that.

 

I've had my car to 140 with the tops off and windows down (kinda windy though) ) and I had a good deal of pedal left. The other guys are right about the tires; and the governer is easily removed with a programmer. Lots of guys are selling these used all over the place-I got one brand new for like $100 . I've yet to use it to change the top end as I have nowhere nearby to got any faster . I would definately invest in tires and a programmer, you can do a lot of adjusting with one.