Douglas Brown

When I got the C3 it did not have Cruise control or A/C for that matter.
upon installing the CC, my main concern was just getting the parts needed and getting connected. Now that I am able to drive it I would like to get this corrected.
1) I find when driving I seem to be slower than everyone else. I had the wife keep pace and report her speed via blue tooth phone at several increments. 50. 60, 70, ect. At 50 I am doing 42, at 60 I am doing 54, at 70 I am doing 66 about 3500 rpms. At 80 I am doing 78.
SHOULD not this be the same 50 is 50, 60 is 60??? and what would cause the diff.??
2) the cruise control button on the tilt column dose not engage the CC unit.
My thoughts are there is not enough vacuum and I need to install a small vacuum unit to in line to help with that.
from what I read and see, there is such a unit used, also some mention of adjustment? on the transducer??

MelWff

do you have the stock diameter tires on the car, 27"?
has your rear end gear ratio been changed from stock?

Big2Bird

You install the correct gears in the tranny to make the ODOMETER read true. THEN, you calibrate the speedo head to match that.
Most heads this age will need re-magnatizing to correct this.
I just had mine calibrated. $45.

Douglas Brown

Tires are P255/R60 15 rear end was not changed.

Tire is 27" % of change from orig. -1.3

I got to thinking after I wrote, speed is determined by the gear in the trans. tires and R-End. not he transducer.

And if it is light while driving that may be a good thing, can not over speed and get a ticket.
DB

Douglas Brown

Calibrated??? Ok... I'll look in to that.....What kind of a shop does this???
I am guessing it is one with a dyno??

Can it be calibrated with out the CC working????

MelWff

i'll bet you have to remove the speedometer from the car to calibrate it and how do you know the rear end gears havent been changed?

Lagonia

I think Willcox does speedo calibrations. Wrt to finding your true moving speed, a ... uh ... windshield mounted GPS unit will be of more use since it does report speed quite accurately.

Douglas Brown

You know you are right. Maybe being light on speed is a good thing I can not get a ticket for speeding.

Big2Bird

A speedometer shop. Yes, you have to pull the head, at least the cluster.

I have one here in Anaheim.

714-535-6471 Precision Speedometer.

Douglas Brown

Thanks, I'll make note of that for when I get that far...Thanks again.
DB