MM951

What can I do with the fuel/timing to get the best MPG on my 951? I am using a maxtronic. I've seen people say they run as lean as 18:1 on idle/part throttle. Is that safe and how much gas does it save?

Can anyone get 27+ mpg on the highway?

mike

Auto_Werks 3.6

epic fail!

zoltan944

When I turn my boost down all the way (10psi) On the highway I get 25-27.
My Max chip runs far more rich than I would like in some aspects and I could get a solid 28+ on highway driving. I am also looking into the Maxtronic to help me do this. Highway map, regular map, etc...

MM951

nice contribution, thanks.

I'm just looking for advice from the people here who have tuned their own cars (ST, Rouge Ant, JustinL, etc) to get the best cruising mpg possible. Is it stupid to save money on gas now?

zoltan, thanks. The maxtronic seems like a great product.. I can't wait to get some time later this week to fine tune my car

I haven't done much highway driving in the 951 (have put very little miles on it.. the n/a is much more economical to drive) but it certainly didn't get 28 mpg. Last time I ran the car it was still on old crappy chips, so I don't know what kinda milage it will get now.

Tom M'Guinn

You can trick the DME into setting a leaner closed loop set point with something like this:

http://www.zeitronix.com/questions/NBpoint.htm

Never tried it, and no idea what the side effects may be in the long run...

MM951

Found the post about the 19:1 idle.. any thoughts on this?

t34418l31

i got 28mpg with cruise on at 80mph over a 340 mile trip with 951 max chips.

Keithr726

Be careful, better safe than sorry in my book. Remember that you can still reach max boost under partial throttle with the lean AFR. The TPS switches the maps around 3/4 and i've seen 10psi at 14.7, yikes. I wouldn't want to mess with AFRs but I guess you could play with the FQS switch on the DME. I hope you have a wideband kit though.

Rogue_Ant

Mike.
I run ~16.5:1 during low load situations (less then 1psi of boost). The best I've gotten for a tank is 31mpg for mostly highway, with some city driving mixed in.

Really anything leaner then 16:1 and you will want to increase lead, due to the slower combustion. The power difference between 16:1 and 17:1 is noticeable.

As for idle. I would say to shoot for 16s. Much leaner and you will most likely sacrafice idle quality. I haven't really messed with it lately since idle takes so little fuel anyway.


-Rogue

333pg333

Keep it in the garage
I can go through a tank of gas in a day if I get on it and that's at probably double your petrol prices. UK is worse. You guys are still way cheaper than most of the world for cars and gas.

zoltan944

any comment on your o2 readings on E85?

Rogue_Ant

Sure, I don't hide any info.

What info are you looking for?


-Rogue

ibkevin

Have to agree there, it's the fastest way to cut fuel costs.

You want speed and economy, go get a motorcycle

MM951

Thanks Rouge

Already have a motorcycle, I don't see the issuse in trying to be economical as possible. Is it a requirement to throw money away when driving a Porsche? I mean.. its free for me to change, why not?

anyway, thanks to rouge I have the info I want...

Rogue_Ant

No problem.

Have fun with the Maxtronic!


-Rogue