Differences between CRX HF with/without FFS

[oldertech]

I was looking on fueleconomy.gov at the 1987 Honda HF and noticed there are two versions. One being FFS and one without that designation. I read that FFS is like a feedback system on the carb that meters the fuel like later fuel injection. But what I wonder is why there were two versions in most every year of the CRX? Do they follow a California/49state difference like my Honda VX? And finally, how do you recognize the difference if you are shopping for a CRX? On the fueleconomy.gov, I see the FFS is much higher in MPG.

Thanks

[oldman]

My GirlFriend way back when had an HF 1984 ish, I have a 96 HX, I think you are asking a 49 state / 50 state question, lean burn makes N0x as does all efficient hot combustion, and I would suspect the CA HF does not ever go into lean burn mode. The HF is a 2 valve engine and its redline is much lower, like 6000 RPM, so that is an easy way to tell look at the tac, the HF has light wieght rims but these are often missing. The HF is really a slow slow slow car the HX is so so so much better and true real world MPG is close enough. 40 ish for a HX, 43 ish for a VX and 45 ish for a HF, no I'm no talking about a no A/C drafting hypermile car, just normal MPG from normal people.