We just bought a 77' 280Z 2+2, love it, runs great... but failed emissions. This is our first old car to tinker with... any suggestions?

 

Welcome to ZDriver!

What made it fail emissions? HC? CO? and by how much?

 

The HC passed
The CO @ 2500rpm was 6.91, idle @ 1.80 limit was 1.5
Only drove it for about 20 min prior. Average speed 60mph.
It had been been sitting for the last six years. Thx

 

High CO means the engine is running too rich, or not completely burning the fuel.

Have you done a tune up? Drain the old gas, change the spark plugs, cap & rotor, air filter, change the oil, PCV valve?

Hopefully you did those things and just didn't mention it (it's a must since the car has been sitting so long).

Also, what is the timing at?