fuel wires

I have the Stock TCU off of my 2018 GT2 AWD, Numbered J57. its perfect for either keeping a spare around, or sending it out to have a tune installed. The only catch being that you should make sure your car's TCU has the same numbers on it. $300 + Shipping I also have a JB4 with the PNP fuel...

Just installed my JB4 + Fuel Wires today. Ordered my Denso's so I'm waiting on those to come in before I start running any high maps. That said, I have ran Map 1 out of curiousity and felt a significant increase. I disabled the JB4 altogether until I receive my new plugs. I have many bolt-ons...

*I am creating this post for those who are not in the initial batches* For the backstory and for those still asking why I did this, please see: 3.3TT - Creating True Plug-N-Play JB4 Harness (w/Fuel Wires) If you have inquiries, and you're in the first three batches, please also post in the...

As the title says, I'm wondering what exactly the fuel wires are doing. My understanding is that they measure the AFR (air fuel ratio) from the O2 sensors, then, somehow, trick the ECU into running leaner. With access to only the MAP and TMAP sensors, is the JB4 just telling the ECU, through...