setting initial timing for gas mileage on 1.0L

Where do you guys set your timing? Is it ok to advance it a few degrees? I would like to try it for better gas mileage but I do not want to hurt the engine any. I have heard that if you go to far you can damage or burn valves.

Where do you guys set your timing? Is it ok to advance it a few degrees? I would like to try it for better gas mileage but I do not want to hurt the engine any. I have heard that if you go to far you can damage or burn valves.

I set most of mine to 5° BTDC per manufacturer recommendation with the diagnostic plug under the hood hooked up with the jumper and blah blah blah... But some of them do prefer a little more. Just make sure your EGR is in good working order. Do some high load driving after adjustment to make sure you don't get any pinging and you'll be fine. If it starts to ping however, you gotta back it out some - because thats bad and you'll hurt your engine. With this in mind, do some experimenting.

-MechanicMatt

And, it also depends on the elevation of where you are driving. If you are at 5000 ft or higher, you can advance the base timing 3 or 4 degrees from the 5-degree standard. So that would be 8 or 9 degrees BTC. (I'm at 6000 ft). But do not do this if you are within 2-3000 ft of sea level, otherwise you'll get pinging and engine damage. 91Caprice9c1 - you're welcome to comment if you have more accurate info on this.

And, it also depends on the elevation of where you are driving. If you are at 5000 ft or higher, you can advance the base timing 3 or 4 degrees from the 5-degree standard. So that would be 8 or 9 degrees BTC. (I'm at 6000 ft). But do not do this if you are within 2-3000 ft of sea level, otherwise you'll get pinging and engine damage. 91Caprice9c1 - you're welcome to comment if you have more accurate info on this.

Excellent input Sas. Thank you for the informative contribution. I was completely unaware that elevation had a bearing on timing :icon16:. Although, now that you've shared this new (to me) piece of knowledge, I can definitely see why it makes sense.

-MechanicMatt

thanks for the advise guys

I own a 94 Metro Xfi and I recently set my timing to 10 degrees from 0 degrees. It feels stronger but I'm worried if I should bring the timing down some. I live in Las Vegas where it's 105 degrees on a typical day. I get about 46 mpg since the timing change. Should I leave it at 10 degrees?

I assume you put the jumper in place when you set your timing?

As long as it's not pinging, it's just fine.

Q

More advance increases power, increases mileage, and reduces the likelyhood of burnt exhaust valves. The downside is increased NOX emissions, mark the original location and turn it back when you need an emissions check. Forget timing lights and jumpering things, every engine, location, and tank of gas requires different timing, the factory takes a best guess to cover the worst possible scenario, then retards it some more to reduce NOX. Ten degrees advance is good for most Metro engines, some guys get away with twelve. Mark the original location, then turn the distributor toward the firewall (opposite the way the wheels turn) about 1/8th of an inch. Go out driving and listen for ping, if you don't hear any, turn it some more. When you do hear it (sounds like small marbles rattling around inside your engine) back it off a bit and tighten down the bolt. You may have to adjust it some when the weather changes or if you change gasoline brands.

I set both my geos at 8-9. They run better in that range. Like the others have said, make sure your EGR system is working. Clean the port that runs from the exhuast manifold thru the head to the egr then from the egr to the TB.

Ok, it makes a little noise at the top end of 2nd and 3rd but it almost sounds like a belt. I am not too mechanically inclined and I have my brother to work on my car most of the time. He did the timing advance per my request. As far as I know the egr is in tip top shape after being replaced 3 months ago. I make alot of trips to Cali from Las Vegas and since the timing change I still average about 46-47 (need to check that agiain) mpg and it's make's the hills alot easier. Thanks for all the advice and I will definitly refer back to this page if I make any changes to the timing.