All-

Here is the document that Mugen's lead S2000 engineer, Takashi-san presented to those who attended his briefing on Monday. It's in MS Word and HTML formats for now. I may move it to a PDF soon but I wanted to post it quickly

http://www.ginsberg.org/TokyoTrip/Docs/Mug...S2KDevPaper.doc

or

http://www.ginsberg.org/TokyoTrip/Docs/Mug...S2KDevPaper.htm

It also appears as though King Motorsports has a much prettier version online already. It is lacking the last page however.

http://www.kingmotorsports.com/products/mu.../tech/s2000.asp

The document covers the following topics:

• The exhaust manifold (headers)
  
• Exhausts
  
• Effects of temp changes in intake air and engine cooling
  
• ECU programming -- VERY important if you already use the Mugen ECU
  
• Suspension Tuning w/ recommended setups

Here is a picture of Takashi-san sharing his test findings with us....



Besides covering the mechanical, he also shared with us the multitudes of aerodynamic tests conducted in a wind tunnel to discover what combination of spoilers and undertrays would reduce lift as well as drag and make the car more stable at the track.

 

Thanks for sharing!! i will take serious look at it tomorrow
goodnight~

 

That's great thanks. May I ask a question on the following:

[QUOTE]The car requires a sever slide (drift) control by the driver.
*Since the car

 

This happened to me pulling out of Texas Motor Speedway and it wasn't fun. I dunno it happened to fast but this could have been the reason. I fishtailed to the left (ass end was to the right) and it snapped back over and I did a full 180 to the shoulder and the car died. I thought it happened because of too much gas, which could still be the case but if it wasn't my fault then this is a bad characteristic of our car IMO, although it is FUN!

 

My interpretation (supplemented with driving experience) is that the S2000 suspension setup is such that rear movement (as in start of a spin) can happen quick enough that the driver cannot perceive it in time to take action, and when action is taken it may not be the correct one unless you can anticipate what the car will do before you actually feel it.. made worse because the stock suspension is not immediately responsive to input under that condition.

 

Thanks guys, did you experience this in normal driving or when cornering with high speed? I had a Miata 1.8, which had of course much less power but it was easily controllable if you would put your foot down in the corner to create oversteer. You could use your senses to turn the steering to the opposite direction and correct the skid. But from what I understand this is almost impossible with the S2K, since the sensitive control is not available.
Is this true? Is it because of the electric steering or because of the suspension?

Cheers

 

What is being spoken of here is not because of the electric power steering, but because of the stock suspension settings.

Moreover, the car is particularly nasty with trailing throttle oversteer. If you let off the gas too much or too fast in a power oversteer condition, you fly around the opposite direction.

The best corrective action is to stay in the gas and countersteer to correct oversteer. Or lift SLIGHTLY off the gas...

Lifting off the gas too much will result in trailing throttle oversteer and that is baaaad, mmmkay?

The guys at Mugen found that the car had insufficient downforce on the rear and the OEM wings and spoilers were essentially totally ineffective. This can't be a surprise to anyone. It depends on how you want to correct the lack of downforce on the rear. There are a lot of choices, but the choices depend on how you drive the car...

Gregg, good work on scanning that stuff, it's excellent information...!

 

In normal or even spirited driving the car is a joy and very controllable. A couple of things combine to make oversteer a noticeable trait that is best anticipated, not left for rapid reaction.

The car is setup to allow the tail to be hung out, but it does come loose rapidly if the driver is not careful and can be a surprise. The peaky nature of the power delivery (especially at VTEC initiation), the LSD, and the fast steering make it easier get a slide started than with some other cars. This is where the

 

Gregg, I will never call you a lurker again

thanks for the info it is very valuable

Hope to see you in New Hope this weekend to hear more about your trip.

 

Damn...you guys got all kind of info out there...sweet thanks!