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Well, I know it can show you the differences of crusing at 55mph vs crusing at 65mph, and it can help with dwl, but I'm still confused about how hard I should be accelerating.

So right now I have it setup to show:
GPH IGN
MPG VLT

In the manual for Ignition Timing it says:
Shows the amount of timing advance (or retard).
The more advance there is (or less retard), the better
for fuel economy and power. The limit is set by the
octane of the fuel, the intake air temperature, and
the load on the engine. A lower than normal amount
of advance for similar temperature and speed could
indicate too low an octane of fuel is being used.

So I guess that means for accelerating I want to focus on making that number as high as possible? It doesn't make much sense to look at the MPG rating when accelerating. I mean if you can accelerate up to 60mph at 5mpg or at 15mpg but it takes 5 times as long, how do you decide which one is better for pulse and glide?

A lot of it is different for every vehicle. Over time, I have found that my 'rolla is very happy at about 1.5-1.7 gph in the summer and 1.6-1.8 gph in the winter. I haven't watched IGN very much.

The way I found my "sweet spot" for acceleration was by listening. Anything lower, it sounds like I'm a big truck. Anything higher, and it sounds like every other car on the roads ;). There is a nice sweet spot that sounds ... not too rumbly and not too whiny. (I think those are the technical terms that mechanics appreciate.) It takes time, but once you find it, and practice it, it will become second nature.

Using TPS as a gauge for a while helped me learn finer throttle control and I still use it when I switch cars to help get used to the different throttles. GPH will give you close to the same information but is more indirect. IGN is cool to look at, but lately I've only used it when I have a flaky idle. Recently I've been monitoring coolant temperature which I would recommend if you do grille blocking.


To find the best accel rate you can experiment under the different scenarios you want on different runs over the same stretch of road under similar conditions--you can use the trip average mpg to measure which works best. The best rate seems to be different for different cars. If you have an automatic you'll probably want to figure out how to get it to upshift a little sooner (in some cars a boost of acceleration followed quickly by letting off the accelerator will force the upshift early once you are close to its normal shift point.)

How do I subscribe to a thread w/o posting to it? :confused: I want to stay updated on this one.

How do I subscribe to a thread w/o posting to it? :confused: I want to stay updated on this one.

http://img520.imageshack.us/img520/148/22333543vs8.th.jpg (http://img520.imageshack.us/my.php?image=22333543vs8.jpg)

I'm new to this too, but maybe the 2400 rpm rule (shift, or in auto, back off to allow shift) is the way to go??? :)

It depends on your car, road conditions, etc., but a 2000 RPM shift point seems to have worked fairly well for most of the 4 cyl cars I've driven. You may want to rev more if you want quick acceleration, are towing, or want to skip gears.

It depends on your car, road conditions, etc., but a 2000 RPM shift point seems to have worked fairly well for most of the 4 cyl cars I've driven. You may want to rev more if you want quick acceleration, are towing, or want to skip gears. Thanx - I will give it a try!! :)