Black Box - proautoman, you assistance please

[95wolverine]

I've read about the performance gains the Black Box has to offer. What I am wondering is on the flip side of the coin.

Let's just for fun say that with the current parameters the system reads, that the truck continually gives a bit more fuel due to thinking there is more of a load thus creating a continually rich condition.

Would I be wrong to assume that this box could actually increase milage by giving the system more accuarate information and trying to better control the A/F mixuture?

Just for fun, if one was to get a 2 mpg increase (we'll use 13mpg to 15mpg) and the price of fuel was a constant $2.35, it would take just under 17,500 miles to pay for the unit if it were $420.

Keeping all else the same, if it were to raise you from 13 to 16mpg, it takes just under 12,500miles to recoup your investment.

Back to a 2mpg increase but fuel at $3.00 / gallon, your number is 13,650 to recapture the expense.

And worst / best case scenario would be $3.00 / Gallon and a 3 mpg gain - yields a 9,700 mile break even.

proautoman, with stock exhaust, a K&N drop in, and a modified airbox snorkel, is there the potential for a milage increase?

[got_titan]

im not proautoman but i can say if you have a rich condition on your truck the box can lean the mixture and save fuel. only way to tell is to dyno with wideband. if it running rick the box will lean it out and you will get better mpg. im sure he will explain better than i did. most trucks seem to come running really rich from the factory so his box is showing gains on mpg on those vehicles

[randyrw]

Unless this box modifies the signal coming from the factory wideband O2 sensor (which is not easy to do) it can't cut fuel back. When in closed loop the ecu maintains 14.7 A/F ratio no matter what. The only thing I see that it may do to help MPG is to increase timing some.

[proautoman]

The Black Box works like this- It takes in rpm and mass air flow (load)
A three demensional map is created in the processor of the black box!
Tuning: Idle and cruise - We adjust the fuel mixture by either adding or
subtracting fuel and various points of load until the Long Term Fuel trims
are perfect or slightly negative! You must have them 0 or slightly negative
so that the tune sticks! If they are positve the computer, by watching what is going on in closed loop fuel control will adjust the Power Enrichment Tables
This will wreck your target air fuel ratio in Power Enrichement down the road!
Tuning: Full throttle on the dyno - There are specific rpm points in which the
Titan has a Supercharging Effect from the intake manifold- These points
you MUST keep the air fuel ratio no leaner than 12.0:1 or torque will crash!
Some may have experienced this from some of the cold air systems that
have a leaning effect (screwing with the MAF Sensor)! After you get the
air fuel for best peak torque you start to lean out (most Titan Mods) to
a happy 12.8- 13.0 A/F Mixture for peak Horsepower! Mileage comes
from keeping the Fuel trims perfect! Some from the fact that many times
we lean out the power enrichment tables - Less Fuel Better Economy!
Everyone seems to be waiting for a tuner box like hypertec- Most of these
are one size fits all with little to no adjustment! Hypertec, Jet and others
would never spend the time like we do having so many different tunes for
all the different cold air boxes, headers, cat back systems,- The Titan
Mass Air flow Sensor is extremely sensitive, there is no way to have
a tune to fit all Titans with so many differnt Cold Air SYstems! They all
have different effects on the air flow calibration! I even thought we should
not try to have a tune for all of the different combo's and just offer a
cold air box /black box combo that is perfect, but so many have all ready
made investments in hardware looking for software to maximize there hardware- We have worked hard to make an affordable solution!

[randyrw]

Hey Proautoman,
thanks for the insite. I can see how that would work for tuning under power. But at idle and cruise when the ecu is in closed loop won't it correct the AFR to 14.7 no matter what? I know from my testing that from a dead stop when I stomp it it stays in closed loop (even at 100% load) until I think around 3000rpm then it goes open loop. And while it's in closed loop under 3000rpm and I have good boost and my aux fuel system is poaring in the fuel but the factory computer is still trying to maintain 14.7 AFR by cutting it's fuel back.
These dang factory ECU are just too smart.

Thanks

[proautoman]

I can fix that- Have fixed the early lean condition on Stillen SUpercharger
with black box tuning- The oxygen sensor - even wide band is the last adjustment to the air/fuel mix! FIrst load (MAF X RPM) then adjust target
air fuel mix- I believe you are going lean because of the response from the
MAF not the computer trying to put you at a target of 14.7:1 with your foot on the floor (wot)
What are you using for auxillary fuel supply under boost?
Extra Injectors? If so what is the duty cycle (on time) below
3000 from your controller Do you have an extra fuel pump
to supply the auxillary injectors! The Stillens were lean up to
4000 rpm and I got them to fatten up on the bottom

[got_titan]

hey proautoman, you workin directly with stillen. here is a dyno with a/f can you tell me if this needs to be corrected? just wandering if im safe with the stillen unit.......double click for a larger view.....thanks, john

[proautoman]

That air fuel looks good to me! Rich where the Titan wants to be and then
happy for the blower later in the rpm I bet that is fun- When did you get
that installed- I was told by Stillen they could not fix the early lean condition
in the rpm up to 3500 rpm. Looks like it is fixed on your graph! i had to
use my "Black Box tuner to fix a couple that a local Nissan Dealer installed!

[got_titan]

this one of the first units shipped out back in october.....truck runs good and strong. dyno guy said the same thing about the graph looking good but said he doesnt tune nissan so he could not tell if it was exactly right.