I'm not sure if this is the right forum or not but I think it is. I have an 83 z28 and it has a th 350 and the gauges are off. the speedo reads 1.5 times the actual speed. EG, when I'm doing 40 it reads 60 and when I'm doing 30 it reads 45. 30x1.5=45. also, my tach is off but I'm not sure by how much. I know that it reads high. my question is is there a way to re calibrate these or would it be better just to get new gauges. would the gauges out of an 89 camaro work? I know that the camaros never came with a 350 so could I just do a gear swap for the speedo?

 

I do not think you can recalibrate.

Could we also get some more details to see why your gauges are off in the first place?
Are these the original gauges for the car, as far as you know?
Does it still have the 700R4 Transmission or was it changed when they swapped in the 350?
Are these the original tire sizes or are they different?

In 1983 I believe all the speedometers were cable fed, I don’t believe they were electronic that year, so if your speedo is off, then you can fix it by changing the speedometer gear in the Transmission, or changing the diameters of the tires you use.

As for tach being wrong, are you sure that it is wrong, how do you know its incorrect, what is it reading at what speeds?

Did these things originally work then suddenly stop working correctly?

Thanks

 

http://www.tciauto.com/Products/Tech...eedo_gears.asp

Open and explore the thread above. To correct the speedo you'll need to know what rear gears you have, tire size, trans drive gear, etc. Plug in the info and look for the correct driven gear to match.

 

The car is a 305 engine with a 350 transmission. It originally had the th 200 but it was swapped before I got it. As far as I know, the gauges are all original. I know the tach is wrong because I bought an aftermarket tach and it reads lower, around half but not exactly. it reads 5000 rpms at 60mph

they have all been this way since I bought the car about 6 months ago.
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what would the drive gear of a th 350 be?

 

Check the following link for some speedo info that may help:

https://www.thirdgen.org/forums/inte...ml#post3727968

JamesC

 

Thanks, according to this information I will need a 7 tooth drive gear, which should already be in there, and a 19 tooth driven gear which will be white. thanks for your help. One more question, will the gauge cluster out of an 89 camaro be a plug and play thing with an 83 or will there be problems?

 

If both are from a V8 and both have gauges (instead of idiot lights), should plug and play.

JamesC

 

thanks!