Thread: Tuning for Gas Mileage

i think you can def bump the timing a few points in the low TP area under 4000 rpms. i wouldnt run more than 40 deg down low probly around 38-39 for your constant cruise area and see how that works.

That's what I'm thinking too, especially if I lean it out, then I might have to retard the timing.

I'm planning on making the timing more linear, that way it's easier on the transmission

has you car been professionally tuned? or are you running on a basemap of sorts?

Calum's tunes, I would say he did an awesome job. Even the guy at the dyno said the tune was very good for a base tune, especially since I didn't gain any WHP over the base tune, only torque.

was wot rich from the start or did you add in fuel to make the WOT slightly richer?

Depending on my setup.

WOT has always been rich, Calum did that as a safety precaution for most people. WOT right now is about 11ish.

Now I said depending on my setup because my WOT will be 11ish with Blow Through and flow stack on pipe before turbo.

If I'm draw through and flow stack right on the MAF, then my WOT is 12.5ish.

Flow stack really does it's magic when it's directly on the MAF, otherwise it just helps with turbo spool.

Here is the A/F graph of the Flow stack on Draw through and no flow stack.

those air fuels are pretty good for a base tune ,they look nice and progressive

So JWT Pop sucks hahah. Gives a little mid range power.

I tried once again to lean out the engine. This time I lowered the K value from 239 to 220. That effectively made the WOT leaner, and I had to lower it to stay under 12.

But highway speeds, 70mph, it was still doing 14.7-15.1, I even changed the fuel map to be 15.95 everywhere that it was 14.7 and it still stayed at regular 14.7-15.1. The O2 sensor just doesn't want to give. Now when flooring the car the A/F would go to 16-17 for a second, kinda jerk, then go to 12 and under.

Last time I got around it by unplugging it and that let me be at 16 A/F, but when I would press on throttle it would not transition as smothley and cause a car jerk pretty badly, with the O2 sensor it's not as bad.

It doesn't help that I have been getting an O2 fault code, P0130, but it goes away and O2 sensor goes into Open/Closed loop without a problem.



Yup, when we zoomed out, it was pretty linear



Well you can't really say that, because JWT was on the DE maf. If I had a JWT just like the BPI or a JWT that would bolt up to the E60 maf it would be a different story.

definitly sounds like the car doesnt wanna go out of closed loop with that not being able to get it out of the 14 range, isnt there a way to setup the ecu with the wideband as the o2 rather than the factory o2 sensor, thats how i have mine setupl i have the plx wideband hooked up to the aem with no stock o2 sensor which i think it would be pretty useless on my setup, but since you are already using the wideband sensor, isnt there a way to get rid of the factory?

i imagne the jerking of the car or hesitation is from the air fuel being leaner, then adding in more throttle and it not transitioning right away causing the slight buck

i was having a simular situation at start up, when i would start the car and drive it right away there was a slightl leaner spot in off boost low kpa and low rpm, where i would give it throttle and it would just fall on its face then it would go, so i had to add in more fuel till i got it to start and go fine without any hesitation or lean spots, which was hard becuase after you start up and go, the car heats up and wouldnt give the problem ,so it had to be corrected right on cold start, so it took a while to get it just right.

maybe with the 16 air fuel ratio you would need to add in more fuel to make the transition smoother. or have the unplugged factory o2 sensor and try to richen up the transition till it gets smooth