90% thats what an ECU does anyway. Give the correct AFR. Why bother o2 sensors if that's not the case. I'm also very confused by this "without an ECU retune" stuff. I've read it in every counter argument. In order to make any modification 100% beneficial (even running the car on 98 instead of 100octane really should be considered) you need a retune. What should be said is, same car, same dyno, with a retuned ECU without the plenum spacer and a retuned ecu with the spacer. A retuned ECU either way is bias but a test without a retuned ECU isn't going to show any 'true' gains.A final point on ECU's; If what you say about allowing more air into and through the engine is true and the ECU cant keep up, the same can really be said for any airfilter, intake or exhaust upgrades. I know that contradicts my above statement but 100% 'efficient' upgrade or not we know that, within reason, a freer flowing intake and exhaust will show power gains.
Dont mean to sound like an antagonist just trying to understand what you mean.
/hijack
I know this is an odd (and somewhat nuebie) question but what is so special that makes the bars so expensive? I mean I have a factory bar from an SiR civic here and its pretty simple. It'd probably take me an hour to copy it. Same can be said for the brace on my SW20.
Please correct me but my understanding is that its meant to be a fairly rigid device to prevent body/chassis roll. If this is that case how much technology needs to go into it? Serious question; I'd rather have a friend tig up a chrome one than spend a small fortune on the same thing with a sticker on it.
Regards
nick