blaSSt

Have a question about the top speed at which cruise control can be engaged. This is a serious question.

I have a 2009 ZR1. Saturday we were in the Big Bend Open Road Race in the 130MPH class. On a long straight we were making up time so we sped up to 160MPH and engaged the CC. It seemed to take, but then the speed kept climbing. We caught it, came out of CC, and backed off to 160. This seems dangerous that the car was speeding up. (BBORR rules we would be DQ'd for exceeding 168 MPH in our class.) Afterward we spoke to another competitor who said he had tried the same thing at 165 and the same thing (speeding up) happened to him.

We know CC works between 126 and 134 but do not know if or where there are limits. There is only a low speed limit (25 MPH) shown in the owners manual. Another person said they thought they had seen a limit in the service manual, but I don't have access to one.

HOXXOH

CC limit is 157. At 158 all bets are off. Speed is also limited to 158 with F55 and a system error and/or until you turn off TC. Been there, done that.

RicK T

Didn't know that.

I just keep learning.

HOXXOH

There are some roads on the way to Ely that make it possible to learn this first hand. Or so I've been told.

blaSSt

Thanks for the info. Still wonder why the CC light came on and the car kept accelerating. Yes the foot was off the gas.

HOXXOH

Good question, but I have no answer for that. Maybe hitting the CC button during acceleration right at the cutoff point is a system fault that GM never tested. I see no logic, but it'd require a program technician to research it.

jbc1995fb

I'm curious as well. I know Tadge doesn't answer questions about the C6, but I wonder if the question was asked about the C7 and worded correctly you might get your answer about the C6.

Sky High

Tadge will answer a question about a C6 but the moderator JVP will not let any C6 questions thru. I asked this question last week in the Ask Tadge Forum;
https://www.corvetteforum.com/forums...with-a-c7.html

jaki30

I suspect if you were to file a complaint with the NHSTB about uncontrolled acceleration, GM would come up with an answer pretty darn fast.

blaSSt

LOL "So was going along on Hwy 285 at 160 MPH....."

blaSSt

So I went to the Ask Tadge and submitted the question about why the car sped up. An unsafe response by the car. I was immediately shot down and told the question would not be sent to Tadge because the moderator "seriously doubt GM did any high speed testing of the cruise control".

What a joke.

Landru