Feedback for my custom AFC project

[Lex]

A MAP responds just as quickly, maybe even more quickly - we have used an oscilloscope to scope out the signal of a MAP sensor. The response time looks like a vertical jump even when the scope resolution is in the tens of microseconds range. Our unit works great on a MAP setup. (tested on a dyno)

The unit's response and processing time is much quicker than the physical movement of the VAF flap. Furthermore, remember that the rate determining step is the speed of the motor itself. Our unit is able to respond fast enough to change the airflow signal of a v8 engine spinning at 8000 RPM several times between each cylinder fire.

However, that being said, the unit has yet to be tested on a VAF setup. I plan to do this in the next couple of weeks (after I get my wideband O2 kit) and I will post the results. I have just been too busy with the GTX swap to get around to it lately.

[EGT95turbo]

A MAP responds just as quickly, maybe even more quickly - we have used an oscilloscope to scope out the signal of a MAP sensor. The response time looks like a vertical jump even when the scope resolution is in the tens of microseconds range. Our unit works great on a MAP setup. (tested on a dyno)

The unit's response and processing time is much quicker than the physical movement of the VAF flap. Furthermore, remember that the rate determining step is the speed of the motor itself. Our unit is able to respond fast enough to change the airflow signal of a v8 engine spinning at 8000 RPM several times between each cylinder fire.

However, that being said, the unit has yet to be tested on a VAF setup. I plan to do this in the next couple of weeks (after I get my wideband O2 kit) and I will post the results. I have just been too busy with the GTX swap to get around to it lately.

In my testing of the Apex'i S-AFC using the OEM VAF and ECU, triggering additional fuel through TPS alone didn't work properly. Not only did the AFC dump fuel before the turbo was spooled, but it did so everytime I accelerated, no matter how gently. Often without the turbo spooling at all. It had to be set this way otherwise, it would run lean if you allowed the turbo to spool.

Another problem occured when accelerating with the turbo spooled, and suddenly having to brake. An exhaust backfire would happen after the throttle closed. It was a little embarrasing to drive it like that.

Fuel economy was terrible and the fuel couldn't be tuned accurately for best power and more importantly, reliabillity. The MAP triggered fuel maps allow the AFC to work well.

Let us know how your test results.
Jess

[Bax]

Any updates on this? It will surely be a fine piece of equipment....

[Lex]

When my GTX ECU comes in, I will create a harness for the AFC and I will do some testing on my GTX. I have been busy lately so things have slowed down with the project. Hopefully within a week or 2, the unit will be driven around in a GTX powered car

[redfox]

i would love to be a test subject

[swalltr207jg]

afc

lex- let me first say that this is a sweet project. If it is possible there would be 3 things that I as a tuner would add to the unit, one would be the size which you have already addressed, another would be 2 plug-ins to the unit, one for plugging a laptop in where you could download the info from the unit to look at graphs and what-not kinda like the one you already created. Second would be a MUST for turbo cars like mine. although the narrow bands are decent for tuning of the afc on non-turbo cars, and shouldnt provide problems for tuning n/a, a turbo car is different, and I think that as your going to be testing this on your GTX you might want to consider a plug-in to the unit that would allow the user to use an optional wideband sensor. Now if its plug in, you could still keep the cost down cause it wouldnt be a necesity for n/a cars, but for us turbo guys we could get more accurate readings of a/f ratios and such. All you would have to do is set the unit to default to the wideband sensor if its plugged in rather then the narrowband. Just a suggestion. wish I had seen this thread earlyer so I could give my input, but alas I cant be online 24/7

[dwpeek]

That is a pretty trick item that you have devised. Is this item gonna be marketed and if so what is you approx. suggested retail? Also, if you need any help R&D contact me.
dwpeek@slmpd.org

[Lex]

Hey guys, thanks for the replies

swalltr207jg: your suggestions make a lot of sense. Putting in a wideband O2 sensor is fairly easy and requires minor modifications to the unit so that is a feature that will be implemented in the near future. Downloading on a laptop is a little more involved and requires some major modifications in order to make the unit "talk" to a Windows PC. That being said, it is a worthwhile feature that will move the product into a more distinguished class.

Unfortunately things have been going very slowly on this project due to me working 2 jobs right now one of which is full time ... and still not being completely done with my GTXed car - loose ends here and there. More time will be devoted to this project closer to the end of June and afterwards.

dwpeek: thanks. I am unsure on the retail price we'd ask for the unit, it depends on many factors such as final costs and number of units produced. Of course we will try and stay as competitive as possible. As for the R&D, I would be interested to know what you can help with, so PM me and give me some more details.

[95ProLeila]

hey, dunno how I missed this, but it's pretty trick. one tiny little suggestion I have is in regard to the LED shift lights. if you watch ALMS or F1 racing and catch the in car shots, you'll notice that the light color changes as you get closer to the shift point (and once you're there the lights blink). now I'm not sure how difficult that would be, but I think it would just be a matter of using different color LEDs no? the blinking is really secondary, but something like a green/yellow/blue might work pretty well. either way, great work, and that's just my $.02!

[Lex]

hey, that change is not difficult to implement. It might be hard to see in the video but the LEDs do become brighter as the RPM increases. There are many things we can do with how they light up/stay on/etc and I think coming up with the best combination is through lots of testing and people givining me suggestions - so thank you for yours

[redfox]

the best thing to do would to have a few choices that the user can sort through, then you can make every 1 happy insted of having 1 design that 1 person loves and some1 elses hates it

[mazdamp5]

the best thing to do would to have a few choices that the user can sort through, then you can make every 1 happy insted of having 1 design that 1 person loves and some1 elses hates it

So how is this Project coming along, I'm doing a bit of a NA monster, and thought one of these would make a great tunning aid, and eta's.

[MD323]

Bump for an update! id like one myself, even an unboxed prototype would be workable, then i can completly intergate it into my dash

[mazdamp5]

Bump for an update! id like one myself, even an unboxed prototype would be workable, then i can completly intergate it into my dash

Hey excellent idea, I', thinking the same, right in where the clock is, we don't need it, most of us have aftermarket radios on our cars, they have clocks in them, and the hazard switch can be moved to the steering column like the escorts.

Humm any chance of it showing boost levels, so and auxiliary boost gauge isn't required.

[RALLYBP_94]

Interested..

BUMP!!