devise808

Hey, looking into picking up a Spoon test pipe for my S2000. I got information on it, in regards to the CEL. The CEL will go on and you have to run a ECG Test pipe O2 Simulator box to trick the ECU. I'm just checking to see if any of you folks have this on your car or if you heard anything good or bad on the test pipe. Any information would be great.

smccurry

I know of someone who has the Spoon test pipe. Your exhaust will be very smelly, and the noise will increase slightly.
I'm sorry but I don't know about defeating the CEL since he's running a Mugen ECU which eliminates the OBDII sensors.

devise808

Did he say, it's worth the money? and if he noticed a difference.

smccurry

It doesn't really give any added power, unless you go turbo or supercharger, and your car will smell like rotten eggs everywhere you go. It improves throttle response, but it's not practical for a non-track car IMO.

Hyper-X

From earlier threads, the test pipe option is one that's been debated often with very differing views. My experience with straight pipes (none in the S2000) has to do with the effectiveness of the exhaust scavenging provided by the combination of the header and cat-back exhaust system. On an otherwise stock car, you're going to increase the noise level some and gain a lot in smell, but real performance gains are negligable.

On Steve's car, he has a single exhaust that's more free flowing than my dual Spugen setup so he could stand to benefit some from the test pipe, but additional power gains are restricted at his Mugen header, just like mine. IOW, to make a straight-pipe count hp-wise, you need to improve flow starting at the header all the way back to the muffler. In my car, I may gain some (primarily due to the Mugen ECU leaning the AF up top) however the sharp bends required of all dual exhaust systems "pinches" the airflow that may counteract the benefits provided by the test pipe. Unless you have a header that's on-par or better than a Mugen up top (7000 rpms and above) and don't have a good single exhaust system, don't waste your time on a test pipe.

Hint: Some may not know this but the gains from a test pipe won't count much without tuning. The OEM ECU is too rich up top and the benefits of a test pipe aren't fully realized. An aftermarket ECU (like Mugen) or a VAFC at the very least is required to lean it out up top (as much as 2.5 points) in order to wring out that extra hp. At 8500rpms on my car with the OEM ECU, we've recorded AF's as rich as 12.1 at the tailpipe which translates to 11.8~11.9 at the cat... hard to gain any power with ratios that rich.

Note: One more thing, as you begin to build a high-performance bolt-on S2000, with an effective CAI, header (like Toda), good single exhaust, straight pipe and aftermarket ECU (or VAFC)... you may want to keep an eye on AF ratios, with a straight pipe, the car will go lean (increasing airflow drops AF ratios a bit). Mine with the cat still installed is already at 13.3~13.8 on average w/ a small spike to 14.1. You don't want to be near 14 too long.

Colin

... And think of all the damage you'll do to the ozone!

devise808

Okay, So I guess buying the test pipe is pissing away my money. All in all, The test pipe would perform the best when you upgrade the ECU and test pipe at the same time, given the fact you have a aftermarket header, exhaust and CAI, Am I correct? As for the ozone and loud factor, I could care less. Thanks for the response. Any who, does any company make a upgraded ECU chip for the S ECU? Those aftermarket ECU's such as Mugen are really expensive, thousand dollar range...

Hyper-X

You are correct devise808.

The ECU can't be "chipped" so the only 2 methods of doing this is by replacing the whole thing (most expensive option but also the most effective). The other is to use a piggyback system like a Greddy E-manage or an Apexi VAFC, the latter being the more popular... however you must have it tuned by a shop with a dyno and wideband O2, don't do this by yourself.