After doing a new version fuel economy tune on OCG35's car and hearing about the excellent results he had (which I did not expect, to be honest), I have decided to pursue additional experimentation with the UpRev package to see how far we can push economy without seriously compromising performance or risking durability.

I undertook version three of the economy tune today on my personal G35C 6MT. Previously, we had used a combination of leaning at moderate to high throttle and low rpms, along with a timing reduction to prevent detonation. This is the basic concept we used on OCG35's car.

In V3 of the economy tune, I performed additional leaning both on various parts of the map, and more timing changes, some of them counterintuitive, but supported by research literature on the topic. I also instituted a change in the ETC maps. I won't get any more specific as this development map did take time and I am in the business of tuning .

As for results, I can only report my specific results which are, at best, anecdotal and biased. I usually focus on fuel economy on my trip to and from my shop. This trip average just under 10 miles each direction and is largely flat with an elevation change of less than 100 ft from start to finish. It consists of entirely city driving with 5 stop signs, 21 stop lights, 5 right turns and 3 left turns. On average I have to stop between 10 and 15 times each trip. Maximum speed limit on the trip is 45 mph and I usually reach somewhere between 50 and 55 mph. Minimum speed limit is 25 mph. Average speed (not including stops) is about 36 mph. Traffic is usually moderate during my commute, with few incidents of stop and go.

Normally, when I'm driving aggressively and enjoying myself, I return about 15.5 mpg on commute averaged over the course of a week. If I try really, really hard and don't get any major traffic issues, I can return 18-18.5 mpg. My best trip ever (car was warm, minimal traffic, did well with the stoplights) returned 20.2 mpg on the Navi economy meter.

Today, I did two round trips to and from the shop driving solely on the econo tune. I made efforts to maximize economy, but I drove at least at the speed limit and usually slightly higher. Nor was I behind traffic off the stop lights. Both trips started with a cold start, one return trip started cold, one was warm start. On the first trip I had a pretty normal traffic and light profile with the exception of a couple stop lights that were out (requiring stopping at each one). On the second trip, traffic was pretty light, the same lights were still out, but I had to run the defroster on the car. Fuel was at 1/2 tank and I am on standard California 91 octane pisswater.

The first trip right after the reflash showed very high economy. I was at 21 mpg average at the end of the first leg, and the return leg got me to 21.2 mpg. The second trip got me to a cumulative 21.4 mpg on the leg out (cold start) and 21.9 mpg on the return leg (warm start) even though I stopped by the store to pick up a couple groceries. Total mileage at this point is 39 mpg on the new econo tune.

I still want to see what happens with more traffic, as stop and go is the worst for economy. I also want to get on a long freeway jaunt to see what I can get there. Typically I return about 23.5-24 mpg on local freeways, and my best mileage ever was 27.5 mpg on a 500 mile trip to Arizona.

I'm not ready to make any major claims yet about the economy tuning as I need to do a lot more testing. And a sample size of one is meaningless. That said, if any of my 20 or so customers who have tuned already with UpRev want me to add an econo tune, I will do at no charge as long as you agree to document your fuel economy with the tune and without it over a regular route (so I prefer that you use your car to commute the same route regularly - the best test would be one week with the econo tune, one week without, etc.). Of course, you must have cruise control to be able to use multiple maps.

I don't think my current gains will hold up, but even they are cut in half, I'll still be up at least 10% in economy in city driving. I'm more interested in having fun whenever I drive the car, so I don't know how often I'd use the econo tune (it is less powerful), but for someone who is hemmed in by traffic and can't really enjoy the capabilities of the car on a commute, or is on a long, boring cruise control trip, it could turn out to be a very useful option.

Shawn Church

 

I'm not a customer but I'd do it I'd be willing to pay as well... as long as I get the info about OCG35's tune down low in the rpms

 

Yeah, sorry about that, I'm really trying to refine it first. Promise me I won't get blamed if something goes wrong for you and I'll send it out to you anyways.

SC

 

Awesome post Shawn! Pretty cool that a "performance" device can double as an econo tool

 

refine?... does that mean more tweaking for me in the future

 

Haha sounds good for you.

Yeah I don't plan on throwing the rom in right away. I have the beta tunable version so I can run the parameters in real time to see what it does. And I have a general interest in tuning and trying to improve my knowledge with it. And what better person to learn from, you are THE Shawn Church

 

What's the status of this development?

 

Interesting...id be interested in doing a few data logs also to see what you can get out of this. maybe even going to extreme lengths of draining the gas tank and only putting one gallon in and do just city driving then do just highway driving.

 

Dang bringin it back from the dead

 

lol i actually just realised the date on the 1st post oops!

 

Any word from Shawn Church? I've been doing some research and can't find anything more as I'm interested in improving my fuel economy.

 

A tune will help your fuel economy in that your engine is running more efficiently, but you might find yourself pushing the pedal harder so all those MPG gains can evaporate very quickly

 

you're missing the point of the thread...

Osiris allows up to 5 maps - Shawn and I initially found that a conservative tune (not aggressive for performance) actually gives better mpg.

It was somewhat of a fluke at first (at least from my perspective)... early on "Econo" was to describe a tune that allows for low octane fuel (as the aggressive tunes require 91 or higher) - "economic" because of course 89 oct is cheaper... but as Shawn outlined in his original posts, he did some testing and found that mpg could also be bettered with the econo tune.

Shawn doesn't spend a lot of time on the forums - he was a huge asset to the G community when UpRev come out with Osiris... Anyone interested in his tuning should give him a call or text.

 

x2

I'm also looking for a good revised econo map, and I always end up here when searching.