De-fueling for economy?

[Jettadoor]

With a trailer hitch out back and no protective ring on the fuel screw, I'm sure someone played with this car at some time in the past to get a bit more oomph.

Since I only need the billows of smoke at wot for clearing sushi out of the tailpipe  :twisted: I think I could reduce the fueling a bit and get better economy.

Any no-noes here? I've 'learned' a little from reading the threads here but "a little knowledge can be bad thing". Can you go too far?

Is there a 'stock' setting on this screw or do you just back it out until performance and starting are unacceptable?

There's probably a lot more to see to but this seems like a fairly obvious and easy place to start. The injectors seem fairly happy where they are and I'm not sure sure it would be a good idea to try to get them out after 17 years unless there's a sure-fire way to do it without cracking the head. 3 days of PB blaster?

Is there anything to be gained by adjusting the boost pin if you don't have a heavy foot?

Nothing's broke and I don't want to try to fix anything, just get a few more mpg.

Thanks for your help  

[FineFrank]

Is there a 'stock' setting on this screw or do you just back it out until performance and starting are unacceptable?

The stock setting is determined by the "ring" that is missing, so now it's trial and error. Back it out at idle until the rpms decrease, and turn it back in until it's smooth again. Then drive it. It's no big mystery; you'll do fine.

There's probably a lot more to see to but this seems like a fairly obvious and easy place to start. The injectors seem fairly happy where they are and I'm not sure sure it would be a good idea to try to get them out after 17 years unless there's a sure-fire way to do it without cracking the head. 3 days of PB blaster?

Not as hard as it sounds, either. Remove the injectors (a good idea to get them tested, especially after 17 years) by pulling the ratchet handle in a parallel direction to the threads. It takes a special socket, but it's not hard. Put lots of anti seize on them for next time, and you're good to go.

FWIW, neither of these things have helped my mileage much (40 city, 60 hwy). If I want better mileage, I have to stop driving like I'm being chased by the devil and unload the excess stuff from the car. YMMV, of course.

[tylernt]

My understanding of the smoke screw is, it doesn't hurt economy if you keep your foot out of it.

PB Blaster on the injectors for a few days worked great for me. Came out slick as snot.

[OM617]

Your right foot is the largest factor in fuel economy. Keep your foot out of it and your economy will go up.

[Jettadoor]

Many thanks for your comments.

Since I had no replies to my post for a day or so I figured there was nothing I could break, so I backed the screw out a full turn. It starts fine but has little power and no black smoke at all. Tomorrow I'll turn it back in 1/4 turn or so at a time until it can get out of its' own way.  I'll find out in a few days if there is any change in fuel consumption.

The right foot is definitely a big factor but I'm rarely in city driving and get passed regularly on the highway, so the right foot's reasonably under control!

As for the injectors, I'm going to wait and see if I decide to keep the car for any length of time before I put any (more!) money into it. It needs a bit of body work to help it through any more calcium soaked winters, so that would be more of a priority at the moment. I'm becoming more and more tempted as I visit this site to get the car back into better shape and keep it as long as I can