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KRAFTWERKS Rotrex Issue

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Old 07-18-2015, 02:06 PM
  #21  
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Originally Posted by Braineack
tl;dr get proper engine management.
Ill give up on my unabridged edition of War and Peace and/or at least stop posting it
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Old 07-18-2015, 02:08 PM
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Originally Posted by jmuse8482
So before you spend 4k because you think its the easy button, think 2wice.
Not many of these kits sold because many here know better than to believe the "easy button"
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Old 07-18-2015, 02:12 PM
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Originally Posted by concealer404
We established that right away. We also established right away that the timing of doing that is impossible.

Not his vehicle, not his say.

Have a anyway.
Haha, it is what it is... but i have at least learned how kraftwerks says it supposed to work, and i clearly know that it doesnt. Brain and every one else is right, but convincing someone to pay 1000$ for a ecu whos *** is still swollen is gonna be difficult.
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Old 07-18-2015, 02:14 PM
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Originally Posted by 18psi
Not many of these kits sold because many here know better than to believe the "easy button"

Agreed, but again not my car.. I had to do the best with what i had.
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Old 07-20-2015, 11:05 PM
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Originally Posted by jmuse8482
Father n Law bought a complete Rotrex kit from Kraftwerks that came with everything. I would like to add first off that the instructions.... HA ! Might as well not been there with a total of 12 pictures "maybe", and literature that looks to have been written by 3rd grader. So here we go, Im not familiar with this piggy back supercard fuel control garbage, was always told it was way inferior Compared to stand alone so i never bothered and it seems to be the case. Got everything installed, Injectors, intercooler, the works. Went for a test drive, and the cruise afrs are strange, rapidly fluctuates from 14-15.8. Went going into boos,t fuel is pulled and car goes way lean (18 afr) then violently swings to 12.1 afr. Which indicates to me that the factory ecu is fighting whats going on to try to keep a 14.7 afr then defaults into closed loop. Fuel card has power n ground and a vacume source but clearly doesnt work. Have not been able to get in touch with kraftwerks yet as i sat on hold for over an hour today.
You are getting some competition between the ECU and your fuel card. What happens is, as you start into positive pressure in the vacuum line that allows the card to read when you go into boost, the card starts adding fuel, just like it's designed to. The ECU, is still closed loop for a moment, and senses the extra fuel as a rich condition, so it pulls fuel and you get a lean transient. Then the ECU goes open-loop and you get rich again, with fuel from its open loop tables and whatever the card is programmed to deliver for the amount of boost it sees. As for the 14-15 AFR variation during cruise, that's normal. The narrowband sensor the ECU reads from only tells the ECU it's rich, or it's lean at short intervals, ad the ECU either adds or pulls fuel in response, to maintain an overall stoichiometric condition. In open loop, it's different.

It took me a while to figure out why I only got the transient lean dependent on how I was using the throttle. If I stabbed it, the ECU went open loop before the card started adding fuel, so I didn't get the lean condition, but if I was more gradual mashing the go pedal, there was that very short moment when the fuel card was ahead of the ECU. I run a Scangauge II, and monitor open/closed loop, so careful comparison between that and my boost gauge and wideband led me to figure out what was happening.

You can try FM's signal modifier, maybe it will prevent this momentary condition. Better would be an adjustable fuel card, best would be a standalone.

I'm using TrackDog Racing's Powercard Pro and it's working well for me, better than I expected after my last system alteration. I started out with KW's original, non-intercooled system that they sold 5-6 years ago. Used my stock injectors (car is a 2000), the non-adjustable 'Supercard', a restrictor in the compressor orifice, 90 mm pulley. Gave me 165 whp @ 5psi, and I ran it like that for a year, and put up with the hesitation going into boost. Then I pulled the restrictor, intercooled, and added the 315cc Supra injectors and TDR's Supercard and Timing card. Power went to a tad over 200 whp @9 psi, and the transient lean spot disappeared. The larger injectors mandated a trick to fool the ECU into trimming them at idle so I didn't get a rich idle and stumbling problems; That consisted of a 24K ohm resistor on a pigtail between the MAF signal wire and ground (another story). I recently went to a 75mm pulley, which increased max boost to 14 psi, and also moved the useful boost over 1000 rpm lower in the powerband. I was worried that the PCPro would max out, as would the injectors, but my AFR's stay between 12.4 and 11.3, depending on how much boost I'm making; I actually get a rich transient now, at tip-in, if I'm using a small throttle setting as I go into boost, a touch more throttle and the extra air puts the 10:1 transient back up to around 12, which then starts dropping as boost increases.

I use the piggyback only because I have to maintain OBD II compliance for state inspection. By far your best bet is a standalone. I only relate my experience as an example that you can improve things with an adjustable piggyback.

As to Kraftwerks' customer service, the only contact I've ever had with them was to call, which was immediately answered; I asked about the smaller compressor pulley and which style I needed, they answered, said it was in stock, and I ordered it, and got it in three days. I was very pleasantly surprised, as almost all the experiences about KW customer service I'd read were echoes of your own.
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Old 07-20-2015, 11:13 PM
  #26  
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[QUOTE=Burnout;1250468]You are getting some competition between the ECU and your fuel card. What happens is, as you start into positive pressure in the vacuum line that allows the card to read when you go into boost, the card starts adding fuel, just like it's designed to. The ECU, is still closed loop for a moment, and senses the extra fuel as a rich ?condition, so it pulls fuel and you get a lean transient. Then the ECU goes open-loop and you get rich again, with fuel from its open loop tables and whatever the card is programmed to deliver for the amount of boost it sees.

It took me a while to figure out why I only got the transient lean dependent on how I was using the throttle. If I stabbed it, the ECU went open loop before the card started adding fuel, so I didn't get the lean condition, but if I was more gradual mashing the go pedal, there was that very short moment when the fuel card was ahead of the ECU. I run a Scangauge II, and monitor open/closed loop, so careful comparison between that and my boost gauge and wideband led me to figure out what was happening.

You can try FM's signal modifier, maybe it will prevent this momentary condition. Better would be an adjustable fuel card, best would be a standalone.

I'm using TrackDog Racing's Powercard Pro and it's working well for me, better than I expected after my last system alteration. I started out with KW's original, non-intercooled system that they sold 5-6 years ago. Used my stock injectors (car is a 2000), the non-adjustable 'Supercard', a restrictor in the compressor orifice, 90 mm pulley. Gave me 165 whp @ 5psi, and I ran it like that for a year, and put up with the hesitation going into boost. Then I pulled the restrictor, intercooled, and added the 315cc Supra injectors and TDR's Supercard and Timing card. Power went to a tad over 200 whp @9 psi, and the transient lean spot disappeared. The larger injectors mandated a trick to fool the ECU into trimming them at idle so I didn't get a rich idle and stumbling problems; That consisted of a 24K ohm resistor on a pigtail between the MAF signal wire and ground (another story). I recently went to a 75mm pulley, which increased max boost to 14 psi, and also moved the useful boost over 1000 rpm lower in the powerband. I was worried that the PCPro would max out, as would the injectors, but my AFR's stay between 12.4 and 11.3, depending on how much boost I'm making; I actually get a rich transient now, at tip-in, if I'm using a small throttle setting as I go into boost, a touch more throttle and the extra air puts the 10:1 transient back up to around 12, which then starts dropping as boost increases.

I use the piggyback only because I have to maintain OBD II compliance for state inspection. By far your best bet is a standalone. I only relate my experience as an example that you can improve things with an adjustable piggyback.

As to Kraftwerks' customer service, the only contact I've ever had with them was to call, which was immediately answered; I asked about the smaller compressor pulley and which style I needed, they answered, said it was in stock, and I ordered it, and got it in three days. I was very pleasantly surprised, as almost all the experiences about KW customer service I'd read were echoes of yours.


Is what it is.... Pisses me off... But, the guys at Good-Win-Racing were very helpful, and so were Flyin Miata.... To Reduce conflict between the fuel card and ecu, my father n law ordered an o2 clamp from FM and are going to use it to limp the car "hopefully safely" through Miatas at the gap... Then order a stand alone. Def not pleased with kraftwerks.
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Old 07-28-2015, 10:54 AM
  #27  
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Like Burnout, I used the Kraftwerks Fuel box with no real problems. I also used a resistor to trick the MAF. I did many track days without issue. I had the older 2 pot "voodoo" box that did need some adjustment. Kraftwerks explained to me how to adjust it. I did eventually switch to an AEM FIC which has better tuning ability. I also need to be OBD II compliant. If I didn't I'd have a standalone.
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