WOT Box write-up

[DK77]

Since I have had experience running a WOTbox from N2MB/npcompleteperformance.com on my BPU 92 TT and my buddy's 16G 93 VR4 I thought I would do a write-up in case anyone else was interested in buying one. Here is a link to them WOT Box - N2MB Racing

First off, why would one want to do this mod? Well it has several features, the two most important ones are a 2-step launch control and no lift to shift (NLTS). It also allows you to enable an ignition-cut rev-limiter which is a good idea since the stock rev-limiter is a fuel cut which could damage your car since it cuts the fuel to the motor.

First off, what does a 2-step gain you? Well with the WOTbox, if you press the clutch pedal then floor the gas pedal, it will engage a user definable lower rev limiter so you can just hold both and the car will stay at, say, 5000 rpms for you to launch. The advantage over normal launching is your right foot stays on the floor so you can focus a lot more on modulating the clutch correctly. The downside of the way the WOTbox works with our tach is that the tach loses it's rpm signal so it bounces inaccurately while the 2 step is engaged. I have a video illustrating what I mean.


Now as for the advantage of the NLTS, what that gains you is the ability to keep your throttle on the floor while shifting. When you hit the clutch pedal with the throttle fully open, the wotbox cuts the signal to the coilpack for a user definable period of time. It also slows down the engine speed rapidly, which will in turn slow down the transmission's input shaft making it easier for you synchros to do their job, and making it easier for you to shift resulting in less missed shifts as well as faster shifts. It also allows the turbos to keep boost while shifting which keeps your boost at it's peak throughout the pull. I have a video on my buddy's 16G car at 10psi from a launch with the 2-step at 5K rpms through the top of 3rd using the NLTS... you can somewhat see how it doesn't lose boost during shifts. The boost gauge is in the stock water temp gauge location.


As for install, it's pretty straight forward, there are two wires that must be tapped into the coilpack, a ground, one to the TPS, one to injector #1, and the only PITA one is to the clutch switch. There are heat shrink tubes zipties, and a loop crimp end for the ground included.

For the ground I just bolted it on the side of the car next to where I zip-tied the box up.


The TPS wire and injector signal wire are just tapped into near the ECU. Stealth316 has the pins for whatever year car you have. Stealth 316 - ECM pin assignments

Now the one that is a Pain in the A**... it is the clutch up switch that tells the cruise whether you have the clutch pressed or not and is a real pain to get to because it's up under the dash on the clutch pedal. I had to lay upside down on the seat and used one hand while trying to tap into it. I tried to get a pic of where it is. This is the best pic I got and it unfortunately doesn't show the actual wire it's tapped into.


The last two are spliced into the power wire to the coils. The red one goes to the side away from the coils, the red w/ black stripe is spliced into the side that goes to the coilpack. We decided to use some removeable butt splice connectors on it so the wotbox could be removed later on without having to re-splice since there isn't a lot of wire to play with.


I think that's everything... it is 2AM though so I may have missed something... feel free to ask any questions.

[AdamVR4]

So the clutch has what appears to be 2 interlock switches, an upper (the switch plunger is depressed when the clutch pedal is on the floor) and a lower (the switch plunger is depressed when the clutch pedal is at rest). Based on search results and the manual, the upper is an interlock switch (I guess this is what prevents the car from starting until the clutch pedal is on the floor?), but the lower is either the clutch pedal position sensor OR the cruise control clutch switch OR the clutch deactivation switch.

When I first started the car, I had the WOT BOX tapped into the (upper) interlock switch. As mentioned, the plunger sticking out of this switch only engages the pedal for the final couple degrees of travel. Therefore, this switch is activated with the pedal at the floor. Intuitively, this seemed like the one to use for the WOT BOX / 2 step / NLTS. Using a quick-connect that was likely a hair too large, I got very little voltage variance out of it (like 0.00 to 0.02 V)...

After some research (outlined above), I decided that I was supposed to use the lower switch... I used a smaller quick connect to slice into the lower switch wiring, so I know I got a good connection. When I started the WOT BOX software:



I had to choose "inverted clutch" to get it to recognize when it was actually up and down.

Of course you also have to choose "OTHER - injector signal" for the "RPM Source" and type in "6" cylinders...

I chaged the launch control RPM to 5000 and the "alternate RPM" to 6000... What the hell am I supposed to do with this? haha

It seemed to make more sense to me for the WOT BOX to utilize the clutch switch that requires the pedal to be floored rather than the one that requires it to barely be depressed... How did you set yours up?

[DK77]

I did it on the one that kills the cruise control. My thought was if you use the one that is for the starter safety, then you will have the clutch disengage before it cuts when shifting (causing revs to jump), and have the 2-step rev limit release to your normal rev limit as soon as the clutch pedal leaves the floor, before the clutch actually engages. In practice, when I was ready to NLTS, I put slight pressure on the shifter toward neutral just before pressing the clutch, as soon as it cuts (as soon as you touch the pedal), the shifter will pop right out of gear into neutral.

I had to invert my clutch signal too. The alternate rpm is an alternate rpm for the 2-step, but I don't remember what parameters need to be met to make it use the alternate LOL.

[AdamVR4]

Okay, yeah, when you look at the clutch switches from a NLTS perspective, the (lower) cruise control switch is the one to use.

Hopefully I'll get to test drive it tonight or tomorrow to see how well it works in practice.

I had to become quite familiar with the "recovery procedure"... The first time I went to write to the WOT BOX, I chose "single feature"... Apparently only early versions were "single feature"... Once you do that, the WOT BOX immediately locks up and won't communicate with your laptop. If you're like me and have a history of bad experiences with USB to serial adapter cables, that might be the first thing you suspect. On the verge of giving up, I explored the recovery procedure, and then had to utilize it about 5 times before figuring out when I could and could not write to the damn box. haha

[DK77]

Ah, you would use the single feature mode if you bought a box that only does NLTS OR 2-step, but I imagine almost all their sales are dual feature boxes since it's only a few more dollars and you get more functionality.