Searched and couldnt find the answer I was looking for. Im sure its a common one but...
What years gauge cluster speedo specifically will work in my 85 and does it have a mechanical speedo.

 

Camaro or firebird? If firebird, 85 is the last year for mechanical speedo, although it got the updated dash. 82-85 clusters should work. If camaro, 82-89 are the same, and mechanical.

 

just 85 will work . 82-84 was the first style and then 85 is the 85-90 or 92 style but 86 went to electric in firebirds . So your like me and you can only use an 85 cluster.

 

i've been searching for this info as well and i have some answers and some questions to add as well.

first of all check this out : http://www.hioutput.com/tech/speedo.html
found it in the electronics board.

there's my answers, here's my question, i have this dumb silver box under my dash called an 870 ecm, and i'm convinced the thing doesn't have circuitry but rather molasses resistors to run the car, if the 165 is bad this thing is a curse, but lucky me i have a 165 on my kitchen table from my donor car.

i'm also stuck with the 85 mph mech. speedometer, and i want to swap to a newer style, after looking at that link i posted, it looks like dash, ecm and all associated wiring will have to be done at the same time for everything to work, which is,, a handfull to do on a daily driver.. any suggestions or further information people could add or experience would be great.

 

hey there. does the mechanical speedo output to the 870 ecm for it's speed reference? if so can you run the mechanical speedo and still swap to the 165 and ignore the speedo outputs from the 165?

 

Take your cluster apart and put a IROC 145mph speedo in its place. Paint the back of it orange and it will light up just like stock.

 

that sounds like a trick thing to do, but wasn't really an answer to any of my questions, anyone else? any more info on this iroc speedo business?

 

the '165 still needs a VSS input. Stock it's set up for optical, which means a signal coming off a mechanical speedometer.

 

So the long and short of it, i can use the 165 before i swap my dash, using the signal provided by the mechanical speedo's little yellow box? would make sense since the one guy swapped a 165 into an 85 camaro and they had mech. speedo's till 89.

guess i'm going to have to oil up the sticking mechanical speedo cable, i would assume if it was jumping around as it does at low speed it could cause some problems with the lockup converter.

thanks guys

 

That's pretty much it.