blown 944

pick away

first I would say though that if you are looking at it from an economic standpoint it would not be beneficial to do the 120 mile RT.

However, from a performance standpoint that is a totally different story. I used to drive 45 miles to get it for my s/c car b/c it absolutely needed it.

JustinL

Here's a quote from Jim, one of the megasquirt gurus that may be able to shed some light on things for you. He seems to think that adding 2 degrees of advance for every point of leaning the AFR beyond 13:1 does the trick. I think the best way to really do a good job is to get some mustang dyno time and really dial in the maximum power in the cruise and low load zones by leaning and advancing the timing until power starts coming down. Obviously don't do this in high load zones or you'll pop the engine in a hurry.

special tool

What is your average mileage today with the car?

Geneqco

Hey Rogue,

Was that with e85 or normal fuel... if the latter, what octane?

Good thread btw... especially the e85 stuff - some great info. thanks Rogue and Sid.

zoltan944

Rouge thanks for the info!
blown 944 thanks for your previous pm info! Your guys thoughts and numbers are pretty close. I have everything I need and I will be E85 ready in 2 weeks

nize

cruise control. can't beat the fuel economy using it.

Rogue_Ant

Don't mind at all.

No problem.


-Rogue

Rogue_Ant

That was with 91octane gas. I doubt I will be able to get that good with E85... I really haven't tried yet because I can't keep my foot out of it


-Rogue

Rogue_Ant

You most certainly can. By accelerating downhill and coasting uphill will improve your mileage. BTW cruise control does the exact opposite.


-Rogue

nize

you know if you do not accelerate downhill, you use zero gas, right?

Reimu

Then how are you going to get up the next hill without laying on the throttle?

Rogue_Ant

Nize, no need to be patronizing. I really don't want to debate the point, besides I don't see anyone else posting about 30+mpg..

Your vehicle requires MUCH less fuel to lightly accelerate downhill then to maintain speed uphill. So by doing this you increase speed downhill and shed speed going uphill. Think rollercoaster.

I would suggest you try some of the things discussed in this thread, especially since you have a stand-alone to play with.


-Rogue

Reimu

Instead of posting a new thread on the other board, it would probably be easier here. There's a new place serving e85 near where I commute weekly, is it worth getting some? Or would it be a bad idea from erroding my fuel system or whatever? (I drive a late '87 by the way)

Rogue_Ant

I suggest replacing the rubber lines before going to E85. Also, unless you have a way to tune the car, and a WBO2 then stick with Gas.


-Rogue

nize

i wasn't patronizing, i was pointing out an obvious fact. assuming you're driving consistently with the same start and end speeds, accelerating downhill and shedding speed going uphill (with the gas down the whole time) vs. coasting downhill (with no gas) and maintaining speed uphill (using more gas) would net an equal amount of gas consumption. this is basic physics.

the advantage to using cruise control, which surprisingly nobody here has pointed out yet, is that it's much more consistently smoother than any human operating the gas for long periods of time. smooth = gas economy.

also, as you have pointed out, my ems has a 'autopilot' mode where if certain conditions are met (minimum tps movement, minimum engine load, rpm change, low boost, etc.), it will automatically run in closed-loop mode and try to maintain whatever AFR has been pre-set (in my case, 16:1). the easiest way to activate this is to turn the cruise control on.

it's too boring to drive this way so i haven't fully tested it yet, but i have some long (400+mile) drives coming up this summer so i'll try it out and report back.