RylisPro

that is the part number for the EPS unit (Electronic Power Steering) in the engine compartment:
39980-S2A-V01 EPS UNIT


I think the right part for the ECU is:
37820-PZX-A21 CONTROL MODULE, ENGINE (REWRITABLE)
which is the same part number on the Hondata website
http://www.hondata.com/flashpro_s2000.html
around $400 bucks

psychoazn

I picked the wrong ECU looking thing.... oops I stand corrected.

wait, whats the difference between 37820-PZX-A14 and 37820-PZX-A21? These are the "current" models, but 21 is compatible with 08-09 only, while 14 is compatible with 06-09, at least according to the dealers...

RylisPro

I am just guessing here...
my theory is that it might have something to do with the CR exhaust as it doesn't have the extra loops a base exhaust has
if that is the case that the stock CR exhaust flows a little more than the base exhaust, it could account for the few extra horsepower
but would it account for the slightly leaner AFR?

the mystery continues...

Harpoon

Hytech header, tp and a good tune on Flash Pro turns the CR into a whole different car. Just make sure you don't try the Toda tune. It is way off on the CR. The fact that some owners of non-CR cars have reported great results with that tune makes me think our car is very different.

takchi

I want to see how much of a difference headers make. If the meet happens, let's see those headers do some work!

psychoazn

before/after dynos please!

headerback + tune transformed the car for daily driving purposes. Not much much on track...

Harpoon

I didn't do a before dyno and I knew I was going to have one of the best tuners in the country do the tuning, so I didn't care what the charts looked like. I told him my goals and he gave me the recommended tune. I won't have the car on track until the end of the month, but the car feels completely different to me - significantly more response throughout the rev range and more power everywhere.

The Toda tune was so jacked up I thought the engine was going to blow. (I flashed the car myself with the pre-set Toda tune before taking it to the tuner). I can't imagine that the Toda header and whatever test pipe Hondata used when making that map would be that different from the Hytech header and test pipe. There must be something very different between the CR and non-CR S2000.

psychoazn

Do you have an after dyno and a "stock s2k" (doesn't have to be yours) dyno from the same place? There doesn't tend to be a whole lot of variance between stock cars, as long as all dynos are SAE corrected.

We're mostly interested in what your header did

As for the Toda tune... well... Takchi and I both have headerback exhausts, but our maps are vastly different. Output in the 5.5k-redline range is pretty much the same, however.

adrs2k

I respect all your track experience, but I think you are making a generalization about header back+tune not helping much on the track. I watch all the video's you socal guys post and on the tracks you drive, I mostly agree with your statement. Personally with the tracks here in AZ and the slow tighter courses and corners I think the header back+tune will help tremendously. Your socal tracks are much faster than what we have in AZ. You seem to be able to keep the revs high and are in higher gears most of the time. That is not the case for people in other parts of the country...

psychoazn

I guess I worded it wrong. I mean for daily driving and lower RPMs, it makes a huge difference, especially before VTEC, but at WOT and at 6k+, there's zero difference to the butt dyno.

Most of our socal tracks do have places where we fall out of VTEC, but its for such a short period of time that it's nearly insignificant. When you consider that you may be out of VTEC for a few seconds out of a lap (and usually somewhere where you're not WOT anyways), and the fact that it doesn't show up on data, its really disheartening.

I will say that for AutoX, it makes a HUGE difference.

How are your track out in AZ? Any track maps I can peruse? I know that the go kart tracks that do car days are assisted tremendously by headerback + tune.


off the top of my head, SoWS involves out-of-vtec on turns 4, 5, 8, 10, and 12 (slowest socal track) and BW involves out-of-vtec on 4, 5, 6, 12, 14. WSIR, ACS, CVR, and Laguna are all pretty much full time VTEC tracks. Except the corkscrew, but its downhill....