So I just bought my 86 Z28 and it runs great. The problem is that when I bought it most of its emisions equipment was not installed in the car (I have all the parts they are just not installed). The EGR valve is still installed however the smog pump and the black canister that rests next to the washer fluid is not in the car. I will be driving this for a few days and will not have too much time to install them back in just yet so my question is will my engine get significantly worse mpg without these components installed?? My car is carbed if that makes a difference. Thanks!

 

Not one bit.

 

Properly tuned for lean cruise, you can easily increase the fuel economy if you aren't concerned about damaging the converters. It will be dirtier (incomplete combustion of all oxygen in the cylinder leading to nitrogen oxide emissions), but you can often lean cruise well into the 16 AFR's and bring fuel economy way up if you don't mind plants and animals dropping dead as you drive by.

Fuel economy and exhaust emissions are not aligned goals. Reducing emissions is all about having the absolute MOST complete combustion event - which occurs at approximately 14.7:1 air-to-fuel ratio. If the goal is ONLY to burn less fuel, you can do that - but you will create more emissions in the process. That's why manufacturers struggle with fuel economy standards - they are fundamentally at odds with emissions standards.

GD