"Should" is the operative word here. I'm still looking for confirmation that a real live Honda S2000 has been successfully modified to run with ITBs - and they have been "available" for the S2000 for years. Although the S2000 engine is as close as you can get to a motorcycle engine, it's still not quite the same.
Is there anyone out there that actually has a running S2000 with ITBs and can show what kinds of gains they got? We can talk "hypothetical, should be" all day long.

Here's an eye opener:
http://www.fjr1300.info/howto/efi-sync.html
The above shows you what's involved in tuning ITB on a fuel injected bike.

 

I can make no claims as to power gains, I do believe on a stock engine spinning at near stock engine speeds they would likely be very little. The advantages aside from "bling" factor would be minimal pumping losses and improved throttle response; ITBs should not be viewed as a power enhancer but more as a supporting modifaction to a system of agressive upgrades that would leave the factory manifold/throttle body setup as a bottleneck. On a stock engine, I see no advatange to ITBs.

That said, There is absolutely no reason why one could not tune a set of ITBs to function just fine on a street car, given the proper tuning tools and know how to do it right.

There are several vehicles that run with factory ITBs, here are a few examples: 4 generations of BMW M5, 3 generations of BMW M3, the Toyota Levins and Truenos that had the 20v 4AGE engine, the Nissan Pulsar GTi-R, 3 generations of Nissan Skyline GT-R, etc.

 

I think we need to direct our attention to the S2000 specifically, as this was what was asked. We have found, over the years, that when modding this car, comparing it to others is not always a valid excercise. What works well on other cars do not necessarily work at all on this one. If it was that straight forward a procedure and worth the effort, we would have many, many S2000s running the streets with ITBs as it seems to have peaked lots of peoples' interest over the years. The fact that there aren't might be an indication of the efficacy of this mod.

 

Good point... Would you say that.. Boring out the Intake Manifold to 70mm all the way thru would be a better Mod vs ITBs??

 

Depends on what other mods you have. It has been well documented here that a 70mm throttle body actually causes this engine to LOSE power. This is in reference to a NA application. Like I said, you must be very judicious about putting stuff on this car based on how well they work on other cars.

 

REALLY!!!.. I never heard of loseing power by adding a 70mm TB.. Right now I have a 70mm TB.. full exhuast, CAI, AEM, Hondata gasket, and I am going to eigther bore out my Intake Mani to 70mm to mach the TB, or just get ITBs.. but not sure thu.. I would one day go boost and I think by boring out the Intake Mani it would be albe to give me better numbers.. What do you think?

 

There was a video named "PacmanS2kvideo" (~40MB) that demonstrated an S2K with ITB's. It seemed to work fine and the sound was great!

Unfortunatly I cannot find an internet link anymore, though I am pretty sure there must be some relative info somewhere on S2KI forum.

 

[QUOTE=xviper,Jul 26 2006, 11:30 AM] I think we need to direct our attention to the S2000 specifically, as this was what was asked.

 

No problems:

https://www.s2ki.com/forums/index.ph...ic=407490&st=0

Check this out. This is the new Fuji Racing ITB setup that's in development... keep in mind that this is just the tuning for the baseline AEM EMS map that will come with the kit, it is a very conservative tune and the car they are tuning it on seems to have some kind of problems (or else the dyno isn't calibrated correctly).

Anyway he is gaining 15whp and 10lbs./ft. of torque with the baseline map, and he is running 47mm air horns without velocity stacks.

 

He posted he didn't do a dyno before the ITBs and he is only getting 200 rwhp with the hood open. Now close the hood and suck hot air and see what you really get.

Don't get me wrong I like ITBs.