The way I read it, launch control is legal if it's a simple two-step rev limiter, even an adjustable one. It's not legal if it futzes with the traction control parameters (or provides new ones), which are specifically off-limits.
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Ahh, so the issue is with the V.S. Pulse feature, not the 2 step limiter. I guess I didn't understand how Josh's setup worked, as I thought it was just a 2 step limiter. Going back and reading through previous posts, now it makes sense.

 

I had my car tuned at King Motorsports over the weekend. Happy with the results overall. Car feels like it has a very nice more usable powerband now. Had a small problem with the K&N intake that a lot of you guys use though. When we made pulls with that intake there was a large wave in the powerband around 7000rpm. The power would go up a bit but then drop down around 8hp and then go back to the smooth gains I had. I was told that whenever they see waves like that it had to do with one of the bolt ons so we tried an intake off of one of the employees Type Rs which had a slightly larger inner diameter and was a shorter pipe. The issue went away right away so I had them fab up a new intake for the car to replace the K&N. Now I just need to make a box to keep it from heatsoaking.

Mods include:
Custom intake (replaced the K%N FIPK)
Hytech header with 2.75" HFC pipe
T1R 70R EM-Limited Exhaust
Hondata FlashPro

Here are the dyno charts though. One shows the first pulls on the stock tune with the mods and the final few pulls after the tune. The other graph just shows the best and final pull. King said that they couldn't remember any S2000s with the same amount of mods that got over 220 on their dyno and that stock AP2s can hit about 205 or so at the wheels. Seems about right for my numbers I think.

 

I'd argue that the EMU launch settings are perfectly legal per the rules, as they are written.

Where is the feedback loop in the EMU 2-step rev-limiter? There isn't one. Therefore, there is no actual traction control involved. It's commonly referred to as "launch control" but it's really just a 2-step rev-limiter with no feedback loops. You set parameters base on surface conditions and you get what you get. The EMU does not adjust anything based on the amount of wheel spin that is sensed through VSS or any other means.

 

That's really interesting about the intake, Colin. You'd have to question the amount of tuning and R+D that went into that intake when they offer the same design for both 2.0 and the 2.2 motors.

 

They thought it might just be the cobination of parts I was using more than the intake design itself. The ID of the K&N was about 2.66" if I remember and the intake off the Type R we used was about 2.8" ID but was about 6 inches shorter. Made a difference though! We even tried a bunch of different filters on both intakes. I'm still using the K&N filter since it didn't seem to make a difference.

 

From Josh's description, it sounds like the EMU is adjusting the limiter (between the two steps) based on the readings from VSS, which may not be legal.

 

The EMU will hold the lower rev-limit for a defined number of VSS signal pulses (user defined between 0 and 40). After it sees the defined number of pulses, it releases the lower rev-limit back to the factory rev-limit. If the EMU could sense wheel spin and make changes to parameters on its own, it would not be legal. However, it's just taking the parameters that are user defined and applying them. There is no feedback in the 2-step rev-limiter system, thus there is no traction control aspect to it.

 

Ok, if this is legal, can you show me in the rules where launch control is allowed.

 

Ok, if this is legal, can you show me in the rules where launch control is allowed.
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14.10 F 1 & 2
1 applies to the AP2
2 applies to the AP1.

I don't see anything in here that says you can reprogram the ecu but can't implement a 2 step rev limiter, therefore, if the 2 step rev limiter is done within the ECU rules, it should be legal.

 

Ok, if this is legal, can you show me in the rules where launch control is allowed.
[/quote]

14.10 F 1 & 2
1 applies to the AP2
2 applies to the AP1.

I don't see anything in here that says you can reprogram the ecu but can't implement a 2 step rev limiter, therefore, if the 2 step rev limiter is done within the ECU rules, it should be legal.
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The parts of the rules you quote say NOTHING about launch control. By your logic, if they don't say that you can't implement a 2 step rev limiter, then I guess since they don't mention that I can't change my hood or the stroke on my 2.0 liter engine, I can do those things? Nope.

Now, you are correct in that you can implement a 2 step rev limiter, but when the car is in motion and the rev limiter is preventing the wheels from spinning past a preset RPM limit until the wheels reach a certain speed (VSS pulses in the EManage's case), that is what launch control is, and illegal under the traction control rule. Does NOT matter the slightest whether or not it is a closed loop or open loop. Any device that limits the amount of power while the car is in motion (other than the actual rev limiter) is considered a form of traction control.

James