Speedo and gauge calibration and adjustment

Speedo and gauge calibration and adjustment

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Discussion

zed4

Original Poster:

7,248 posts

221 months

Thursday 16th February 2017
quotequote all
Good morning,

The speedo in my LS3 Griffith is so far out that it’s completely useless. I’ve recorded 294 miles since I bought it on the trip, but according to the route on Google maps it’s only 230 miles. That’s over-reading by nearly 30%! I will need to go out for a drive with a GPS and get some accurate speed comparisons. Can anyone recommend someone who is able to recalibrate the speedo for me? The temperature gauge also seems to over-read, so I’d also like that calibrating.

Thanks,

Dan

nawarne

3,088 posts

259 months

Thursday 16th February 2017
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Dan,
Steve Farwell calibrated his Chim speedo via some inputs/buttons on the speedo 'drive' behind the gauge panel. His car is a 2000 model with the relevant type of later gauge. Bit of a trial and error process but I believe it's pretty accurate now.

Re: the temp gauge, have you access to an infra red thermometer? Can be bought pretty cheaply from Sealy etc. You'd get a cross check on the actual versus the indicated readings - maybe gauge is not reading high? Have you considered that the LS engine might be making greater demands on the cooling system? And, if the rad' leak was starting then the cooling would be compromised.

Nick

zed4

Original Poster:

7,248 posts

221 months

Thursday 16th February 2017
quotequote all
nawarne said:
Dan,
Steve Farwell calibrated his Chim speedo via some inputs/buttons on the speedo 'drive' behind the gauge panel. His car is a 2000 model with the relevant type of later gauge. Bit of a trial and error process but I believe it's pretty accurate now.

Re: the temp gauge, have you access to an infra red thermometer? Can be bought pretty cheaply from Sealy etc. You'd get a cross check on the actual versus the indicated readings - maybe gauge is not reading high? Have you considered that the LS engine might be making greater demands on the cooling system? And, if the rad' leak was starting then the cooling would be compromised.

Nick
Thanks for that. I need to take the dash out so I'll take a look.

I will get an infra-red thermometer, was planning on buying one.



Edited by zed4 on Thursday 16th February 14:17

Steve_D

13,737 posts

257 months

Thursday 16th February 2017
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Don't know how it is done on your car but worth researching if yours has/needs a voltage stabilizer. As the temp gauge (and fuel for that matter) works on measuring resistance then voltage difference will skew the results. Modern gauges have it built in but older systems have a stabilizer mounted on the back of the dash.

Steve

Discopotatoes

4,101 posts

220 months

Thursday 16th February 2017
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You've just bought this from a reputable company. Have you had a conversation about your woes with them?

zed4

Original Poster:

7,248 posts

221 months

Thursday 16th February 2017
quotequote all
Discopotatoes said:
You've just bought this from a reputable company. Have you had a conversation about your woes with them?
Yes, I've no issues with Topcats. I'm just sorting out a few niggles. Radiator is being tested with Radtec at the moment to see if they can find the leak.