I have an 86 IROC with original temp gauge. It has a caburated LS1 engine with no computer. The temp gauge goes straight to 260 after I run the engine a short time (30 secs.). I'm wondering what sending unit is compatable with the stock gauges.

 

Welcome. My first question would be what brand do you have installed currently? I had a store brand that exhibited the same symptoms, and a genuine AC Delco unit resolved the issue.

 

Do I buy one for an 86 Camaro or an LS!?

 

AFAIK, the actual sender is dependent on the head, where it should be located. You'd get an LS unit. This is all assuming you don't have a short to ground from the sender to the gauge.

 

If you are relying on the 86 Camaro's stock dash gauge for coolant temperature, you need to use the same sender that your 86 Camaro engine used for the gauge..