It has to be in the software. I used to get 30-32 hwy With the JCW kit. Since the addition of the JCW larger injectors, cam , larger T/B, crank pulley and retune on a Unichip I'll get about 280-290 on a tank off gas. Roughly 22-23 mpg tops. I'd be very interested in the BBR software if you get the mileage you say plus the performance.

 

That is similar to my gas milage....... 22ish

 

Well, I can say there is something to better fuel economy as it relates to this software. The claims of 39 mpg, I haven't seen, but the car is heavily modded. Before the gears, it was definitely better with more mods than it was with less mods and the Shark injector. With an accurate OBC or not, there seems to be a 2 - 3 mpg loss in fuel d/t the gears, which may be minimized if i slowed down to 60 - 65. Though BBR's software is amazing, but before you go buying it, let me do some calculations based on actual fuel consumption and milage.

 

Cosmic Purple - SpiderX
Thanks for the info. I'll wait for your info on mpg, but I'm going to get some info on the BBR software. I'm waiting to hear about M7's new software when they announce their new product's. I don't really need a 8100rpm redline, but I could use more than I have now. I hit the rev limiter at the Glen on the back straight and I could use about 4-600 more rpm in 5th. Thanks again.

 

I would like a 7500 redline... I have a Unichip so I am waiting for some development......btw I grew up in Buffalo and visit every summer

 

Just to be clear, are you saying that you need to multiply what the obc says by 13% to see your true mileage on the road? It's quite the opposite from my experience- I easily lost 13% in actual gas mileage with a given obc reading after 400cc injectors. This makes complete sense to me, because larger injectors work by taking in the same voltage and giving out more fuel per unit voltage, hence worse fuel economy compared to the computer.

 

How 'bout just doing it the tried and trued way. Fill up the tank, reset the trip meter, next time you fill up, write down the nunber of gallons it took to fill it up and divide the miles (from trip computer) by the gallons.

 

Multplyng by 87% gives you the number. It's 13% less than the OBC reading.

 

Ha! A sandwich!

 

wrong think, Ing. the ECU reads the A/F, throttles back the number of pulses from the larger injectors, and the computer reads that as requiring less fuel

 

Not exactly, JLM [as far as I've read]... The ECU can adjust, but only give or take 20% based on what it's seeing at the AF sensor [which as a narrow band reads strikingly uniformly when rich vs. lean- almost as binary, 0 vs 1!]. Look at the links that I provided, if you have a sec. They're pretty clear about emissions loops.

BUT, they can only adjust fuel trim based on AF info in CLOSED LOOP, ie when not at full throttle! On a dyno/at full throttle, you are going OPEN LOOP, the ecu doesn't care about AFs and it just reads off the program. So, you'll run a lot richer in open loop and probably pretty rich still in closed loop with larger injectors [even after the ecu tries to compensate], without writing good tables. I still believe that the injectors, which take in a voltage and spit out a quantity of gas, vary in their gas given per unit voltage [by having different impedences, likely].

Do you understand where I'm going with this?

As an aside, in the MTH Tuner thread, I wrote that maybe there's NO adaptablity to the open loop program [makes sense, it doesn't use the AF data], but some adaptability to the closed loop program [because it is the one that cares about whether our cars are running lean/rich], and this is why some people notice increases in power with driving a few hundred miles after a reset, but Andy has seen no difference on a dyno...

 

Your belief is once again not backed up by reality. Injectors do not have the ability to "vary in their gas given per unit voltage". Inside each MCS injector is a pintle that is actuated by an electromagnet. When it gets pulled up by the electromagnet, fuel flows. When it's not getting pulled up by the electromagnet, a spring holds it closed and fuel doesn't flow. The injectors are supplied with continutous voltage on the upstream side of their circuit and the ECU opens each one by completing the ground path ("pulling" it to ground). The quantity of fuel delivered is varied by either keeping the injectors open for varying lengths of time (pulse widths) or by changing fuel pressure across the injectors.

 

Cool info, but ultimately the electromagnetic mechanism is effectively a resistor, correct? It gets power [an ELECTROmagnet]. By definition, fuel delivery varies depending on power applied in the circuit [P=V*t]. Right? Regardless of whether it's a voltage changes or the duration does, these are not magical electrons . Power in equals work out [save some losses].

I didn't know how the relevant difference in voltage worked, now I do, BUT I did know that varying electrical power [NOT through a computer data link] worked its magic. Thanks!

edit: FWIW, for completeness's sake, you can also increase fuel delivery by changing the resistance across the fuel injector [besides changing the pressure or the pulse widths].

 

So, who is using infinitely variable injector voltage?

 

I edited my post shortly after posting, yet apparently not before you read it. Sorry about that. My meaning is now conveyed.

You still didn't address my theory on power increase with ecu learning. Thanks!

 

Who is doing this and how are they doing it?

Is this another example of stronger valve springs making the valves open quicker?

 

Nope. Sorry, just some basic physics for you, because I know you love it. Less resistance across the injector equals more current. P=I^2*R. But, you knew that.

A little grumpy today, old man?

 

Sure, and water-cooled turbos are in place to cool the intake charge, right?

Back to reality, injectors do not typically function in the way that you describe, certainly not in the case of the MCS. Here's a great book that should help you with lots of your theories:

http://www.bentleypublishers.com/pro...&subject=5

 

Do not typically != [does not equal] Do not . Again, I said, "it is possible" or such like that. Chill .

 

Sure, anything's possible. But, in the real world, injectors don't work like that.

BTW, you should start a new thread discussing your fascinating baseless theories to keep this one on topic.

 

Well, you seem to be the only one interested, as you began this line of posts, so pm me if you wish .

Yes, fuel economy with the gears was the topic, and I was interested in why Purple was doing what he was doing. I was concentrating on the reason for good/bad economy.

From now on, if you want to discuss stuff like this, again, feel free to pm. My box is usually not full [but, yours seems to stay full, so I can't pm you this!].

Purple, I'm looking forward to learning about your observed mileage on the road. Thanks for doing this for us, man.

 

the issue, questioned by Ingsoc, was about the 13% correction cosmic made to the computer calculated mileage; a correction made because the computer is using pulses to calculate fuel used and since the larger injectors are squirting more per pulse and since the ECU will therefore cut back the number of pulses to hold A/F (except at WOT), a correction is reqiured.
Insoc needs to get back to reality from time to time

 

FWIW, my OBC runs 10+% optimistic on a completely stock car - I would think that bigger injectors would make more than a 3 point difference.

Cosmic - did you check the reality/OBC delta before the injector change?

 

NO, but i am working on some real time data. I should have some figures in the next week or so.

 

Peace. Here is some real time data dividing distance traveled by amount of fuel used.
In the city, that is both on highway and off with more than moderate use of a heavy foot, the average was 20 mpg.
On the highway, driving about 2/3 of the time between 65 and 80 with the other time spent having much fun, I calculated 27.9 mpg. I'm sure if I established enough self discipline to let others pass by without playing with them, it could probably be around 30mpg.
So... I don't know if it's the software or not, but i am thoroughly impressed given the gearing. Overall, it appears to have been a very good move in terms of performance and not so bad in terms of fuel efficiency.