MPGs run, Aspire SE

[TominMO]

Dios mio!

[Pu241]

I wonder if you all are going to force me (via peer pressure, death threats, promises of chocolate, etc) to eventually buy this:
http://www.diyautotune.com/catalog/m...ans-p-500.html

Yeah, been wondering if that is what it will take to booster MPG into the 60+ range.
But, still want to see how far you can take it with this approach first.

[TominMO]

OK, fellow talking monkeys, here's what happened today:

Jumped in the car, warmed it up on the drive to the grocery store. Adjusted the cam timing to -2, and set base ignition timing to 13 BTDC with the light. Bought groceries, then went for a short city/hwy loop to see how it ran. It did pretty well; power was smooth up the RPM range, but seemed a little low. It idled a bit rich, in the 12s.

Then I changed the cam to -4. When I went to change ignition timing, I found out that the disty was already advanced to its mechanical limit. The timing light told me it was ~9 BTDC. So I left it there at 9, with -4 cam, and went for another drive. This setting also ran smoothly and seemed to have more power; also, it idled a little leaner, in the high 13s/low14s.

Since I couldn't advance the ignition any more, I called it a day. I don't see any point in advancing the cam to +2 or +4, esp. for attempting better fuel economy. What I might do is pull the disty and extend the bolt slots with a rat-tail file, to try to get more base timing in. Or, I could deliberately install the cam gear one tooth retarded again, and give me a cam timing range from -20 to +4 (instead of -12 to +12)! That would give me a wide range of ignition timing to play with.

But first I will go on an extended run with this configuration to check if it throws a code, and see what mileage it gives me.

[zoom zoom]

I wonder if you all are going to force me (via peer pressure, death threats, promises of chocolate, etc) to eventually buy this:
http://www.diyautotune.com/catalog/m...ans-p-500.html

Get one for a protege!.... Do they have kits for a b6 323? That would be plug and play on a Festiva.

[TominMO]

Get one for a protege!.... Do they have kits for a b6 323? That would be plug and play on a Festiva.

Read that page closely; it seems to be for all B-series motors. They don't mention the NA B6D on Capris, but I bet it would work there too.

[eurotiva]

Do it Tom! Then you can adjust timing on the fly, and datalog, for later research

[TominMO]

Went out and installed the cam gear two teeth retarded. Meant to only do one tooth, but was a bit sloppy. But the upside is that I now have huge overhead in ignition timing! My minimum cam timing is -4 (technically -3.65), which is fine with me. I set the base ignition to 13 BTDC, and there is plenty of ignition-timng room to accommodate increased cam gear retardation. Going for a drive tmw to check mileage/code-throwing.

[jason_]

I had to hog dizzy slots to make 10* factory after my head shave when using factory line ups. Hehe he. I ground off too much material.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[FestYboy]

Tom, i thought the whole point of this was to INCREASE mpg, not power above 3k...

[TominMO]

Tom, i thought the whole point of this was to INCREASE mpg, not power above 3k...

But I want it to run well too. For now I want to keep ignition timing a constant at 13, and adjust cam timing. Once I get optimal cam timing, I will vary the ignition timing to find an even better solution for mileage.

[getnpsi]

heh festyboy. that is the subjective part of being objective. When you increase tq you feel it and wanna feel more of it. Toilet mileage. Skip shifting at low rpms with more oomph is great until you take off from lights and brag about chirping tires when you couldn't before==toilet mileage again. moving your power up the curve is ok for gains if you are responsible and drive it nice, knowing your power is later for highway buzzing...if you don't wind her all the way out in 2nd and 3rd because the exhaust note sounds better with a header...toilet mileage yet again lol. I don't know if every approach works for every occasion. I had a 1997 aspire for a little while and was able to monitor a few extra things realtime. Making the car down on power on purpose does work for mpg runs, with a b6 I think you have more wiggle room than with a stock b3 engine. Right now priority one is to dial it in so you don't get engine lights and stumbling with radical temperature swings, then getting back into aero with the weather getting cooler and so on. A rounded off cam with new valves would get great gas mileage but no power low or high, think boat anchor late 1970s v8s, iron blocks that would not take kindly to any ignition timing advance

[TominMO]

What I'm not sure of is if I should be starting with cam variation, then switch to ignition variation, or the opposite. But I have to try something, and this makes sense to me. Rightly or wrongly, I believe that a slightly more-advanced ignition (13 BTDC instead of 10) will give better mileage, due to more-efficient burning.

It seems to be making good power and it feels quite smooth. Some of this is no doubt due to Matt's header. I'm thinking of taking it to a local dyno shop to check power at whatever cam/ignition configurations seem to work best for mileage. Three pulls for $75.

[eurotiva]

Make sure to ask if you can adjust between pulls. Most shops charge extra for the extra time

[TominMO]

Make sure to ask if you can adjust between pulls. Most shops charge extra for the extra time

Yup. But why would they sell you three pulls and not let you adjust? You should get basically the same results for all three if adjustment is not allowed. So no one would pay for that service.

BTW what's the latest word from Hollywood? Got an agent yet?

[TominMO]

Went on a run today for 114 miles, with cam @ -4 and disty @ 13. No code thrown, thank John. Ran pretty well but tended to die when idling in neutral. Gas mileage was 51.8 MPG. The AFR meter oscillated from 13.x - 16.x in steady cruising @ 60 MPH.

Came back and set cam to -6, and reset timing to 13 again. Will go out again tmw for a short drive just to check drivability. I don't like the dying at idle thing; not acceptable for a DD. Then next Wed I will go on another longer run to check MPGs with this config.