this entire topic is a question that has been asked time and time again. the problem is, there is no right answer. it really depends on a persons' automotive interest. with that said, let me give my two cents:
i, personally, autoX and run canyons, and through experience, i believe N/A is the better choice for these type of activities. i noticed a very biased comment about N/A on the topic of LSD. let me clarify that lsd is not for the sole purpose of better launching. let me quote Kaaz:
when the car is turning at higher speeds, the car will tilt to one side, and you hear the squelching sound. The car doesn't tilt as much as you see in the action movies, but tilting still occurs. When this happens, the normal differential puts more power on the wheel that is in the air, which is useless until the car is out of the turn. This is where a KAAZ L.S.D. can help to reduce the loss of power transferred to the wheel.
As you may already know, a race driver wins their race from gaining time when they are cornering. For this reason, many car manufacturers keep trying to make cars turn more efficiently at a faster speed without slipping out of course.
http://www.kaazusa.com/features.html
N/A is also good for autoX because of several other benefits. N/A does not add any weight. though many of you laugh about this, it is true that every pound you can save is worth it. why else would a person buy a carbon fiber hood? if you say for looks, again thats another view, not N/A nor turbo, but show. but think about it, you take out the cams and replace them with new ones. same with valve springs, throttle body, port and polish, etc. weight addition is minimal to none. place a turbine, an intercooler, blow-off valve, etc. your adding unwanted weight. another advantage of N/A over turbo is turbo lag. you wait for the turbo to spool then comes in the power. many of you say its not much but with the constant shifting throughout the track, this lag could be costly. N/A is the obvious choice when it comes to track, simply why all the rsx's today that compete in autoX are N/A. (i.e. realtime rsx).
however, it's not say turbo is bad. turbo is a good upgrade to any engine if horsepower is strictly what you need. when it comes to horsepower, F/I is the way to go. no N/A can ever compete with a twin turbocharged NSX engine (AEM rwd civic). but thats drag, which is fun too, but not my cup of tea. when it comes to money to horsepower ratio, again turbo wins here. for the price of a a toda kit, along with CAI, headers, exhaust, pistons, and the like, you can get a Greddy turbo kit and intercooler, with a HKS super sesquential blowoff valve, and maybe even a boost controller. the power difference would go hands down to the turbo kit.
so, now you've seen my views. personally, i'm an N/A guy. but thats just because of what i do and how i think. if anyone else disagrees with me its because you think differently than i do. before i end this, i want to say something about that comment on steve's civic. just because the k20a3 came out on the base rsx first doesn't limit it to an "rsx engine." if steve is driving the ep3 then the engine is same as the base rsx. you can't say 'i thought he was running the "civic engine"' because the civic si came with a k20a in the first place, what "civic engine" could you be refering to?
