MAP vs. AFM voltage
 

When building an emb injection map, is it best to tune using MAP sensor voltage or airflow meter voltage on the verticle axis (rpm on the horizontal axis)? What are the advantages/disadvantages of tuning with each?

On a '94, you could plausibly use either. With a 1.6 car you have no choice but to use MAP since the AFM hasn't enough range, but with a hotwire MAF you could get away with tuning to that.

Personally, I find the MAP sensor more useful since it is an absolute indicator. IOW- you know when you're making boost and how much. With a MAF, you don't have that certainty since the airflow will be different for different RPMs.