New ITB (Independent Throttle Bodies) ASM Kit for the NSX

I ordered some ITG sock style filters to use as a short term solution while I work out the plenum. I'm sure they'll rob power but be better for my engine by far and after spending almost 4 months on the install and initial programming and tuning I just want to drive the car again and not worry about it.

Also if anyone has any magic solution for crankcase ventilation with an ITB setup I'm all ears, the only thing I've come up with is exhaust scavenging but that seems to be questionable at best. Right now I just have both valve covers T'd into a catch can then vented to atmosphere near the tail pipe. With a plenum, the evap situation is easily solved by plumbing the vapor canister into the intake and I could dump the catch can into the plenum as well but that won't provide any crankcase vacuum.
 
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Also if anyone has any magic solution for crankcase ventilation with an ITB setup I'm all ears, the only thing I've come up with is exhaust scavenging but that seems to be questionable at best.

Are you experiencing excessive blow-by or carbon build-up?
 
No issues with blowby or build up or leaks or anything, my catch can is still empty, I just want to keep the benefits of a ventilated crankcase. I've been talking to Adnan about the possibility of driving a vacuum pump off of a camshaft but the packaging will be tricky.

Basically I want to have my cake and eat it too.
 
No issues with blowby or build up or leaks or anything, my catch can is still empty, I just want to keep the benefits of a ventilated crankcase. I've been talking to Adnan about the possibility of driving a vacuum pump off of a camshaft but the packaging will be tricky.

Basically I want to have my cake and eat it too.

Not even mad at 'ya!

I run the SOS oil catch can that vents to the atmosphere from both valve covers with a line to the intake tube (stock airbox to intake tube to ITB airbox). No indications of blow-by or carbon build-up. Combustion chambers look great (smart phone boroscopes are awesome) so far with mostly street driving and a few track days thrown in since refresh.
 
I've had quite a bit of milky soup in my catch can but I attribute that mostly to aggressive canyon driving while having my catchcan mounted lower than the rear bank breather tube outlet. I'm convinced that one day I'd like to reposition that cam cover inlet up to the top instead of to the side. It looks ugly from the top though.
 
Lol all this talk of catch cans ..I thought I was over at Hellcat.org....:biggrin:
 
That's an absolutely gorgeous airbox!!

I couldn't have articulated it anywhere near as well as @A.S. Motorsport. I'm the forever tinkerer so of course there are still a few areas i'd like to improve but i'm very happy with the setup thus far. This could definitely be the forever setup for me. Overall, this setup has worked out surprinsingly well. The drama is fantastic.

Be sure to check out @MotorMouth93 's thread. He's making huge strides using the factory ECU to run off the ASM ITB setup.

Here's my airbox solution for those interested.

AM-JKLWBDBzpRbaaWfhqOTLvRlbDSr75z9CJDMpO3SDlfGFoDQgOQBDkcEYR6OxSjMZ6VwNYvvXNqqa3RfvKEMmsfhks7fL2jID1TPr_FdNgqIZ0CsDzVtLO9JsEM9pBzGbRZSlIXrh3LEBpAxDpbcXiPunovA=w1292-h969-no


Without the plenum
AM-JKLW_iwIFTavzAIZDUd-_JLVhaLqZrDym_MDjhns6F3_cdmo75Qca7QV3s6Y05lZypRU-Qqvr5WHo0Kb8vcN05C_tdJCrCw5SL1y293MFz76ml8-dHlSHwMw11AhPzsSpiNHguCv9wVfaq6Ys57JfCVAgCg=w727-h969-no


What an absolutely beautiful piece. It's a shame to have to hide ITB's (I'm very much in the pro-airbox camp when it comes to ITB's) I can't think of a better looking airbox than that one. Looks like something from GruppeM. If you don't mind my asking, who made that?
 
No issues with blowby or build up or leaks or anything, my catch can is still empty, I just want to keep the benefits of a ventilated crankcase. I've been talking to Adnan about the possibility of driving a vacuum pump off of a camshaft but the packaging will be tricky.

Basically I want to have my cake and eat it too.

RYU and Motormouth93 if you would reach out to me on PM. I've been emailing with Adnan and want to improve the sound (and not for HP gains) thru ITBs. Unless your ITB builds are somewhat plug-and-play now, for my (hot) Miami street use, ITBs are probably overkill for my (OEM) 2003 LBBP NSX. I could probably send the car to one of you for tuning.
 
Oy vey. Though I get it. No free lunch. I'm sure there are tuners down here in Miami Beach. But I really don't want to change some thing that's near perfection to start with…
 
RYU and Motormouth93 if you would reach out to me on PM. I've been emailing with Adnan and want to improve the sound (and not for HP gains) thru ITBs. Unless your ITB builds are somewhat plug-and-play now, for my (hot) Miami street use, ITBs are probably overkill for my (OEM) 2003 LBBP NSX. I could probably send the car to one of you for tuning.
Wow! I had no idea you even got back into an NSX. Welcome back @serialNSXer !

I'm certainly not a tuner. I barely trust myself in front of a computer for my own stuff, but the hardware itself is stout and I stand by Adnan's kit even in hot/humid temps like FL. In terms of driveability nuances, i've gotten mine to be as "reliable" as my old CTSC kit. I'm on the AEM Infinity standalone. While it's far from my favorite, it's done pretty well so far. If money is no object, skip the AEM and go for something better though.

I'm adding Drive By Wire throttle actuators to my ASM ITB setup now. You can follow me on IG stories @ryumoto_ if you care. For your 2003 you'll need a DBW setup to limit the amount of rework. ITBs on any NSX is a bit of a project though but everything should be bolt-on affair by now.

With that said, I'd like to understand what you're looking to accomplish exactly. Is it just for sound? The ITBs are intoxicating at any RPM and the throttle response is crazy quick but to get the most out of it you should at least have a lightweight flywheel and a free flowing exhaust. Do you plan to keep the trumpets open or do plan to have a plenum built of some kind?

For me, there's no turning back. I'm an ITB NSXer for life. It's too good and really compliments how I built the car. If my car was relatively stock, would I do it? Probably not to be honest.
 
For me, there's no turning back. I'm an ITB NSXer for life. It's too good and really compliments how I built the car. If my car was relatively stock, would I do it? Probably not to be honest.
I requested to follow you on IG.

Curious about your last statement...what would you do (if anything) if you had a relatively stock nsx like mine?
 
I requested to follow you on IG.

Curious about your last statement...what would you do (if anything) if you had a relatively stock nsx like mine?
What's your IG user and i'll look for it. I try not to add too many followers on there.

For a stock NSX: I/H/E and a short gearset. Maybe an LSD. Bucket seats, oversize brakes on stock calipers. It really depends what kind of roads you enjoy driving the most and, of course, how much you want to spend. If you have money burning a hole in your pocket then there are many other things.
 
What's your IG user and i'll look for it. I try not to add too many followers on there.

For a stock NSX: I/H/E and a short gearset. Maybe an LSD. Bucket seats, oversize brakes on stock calipers. It really depends what kind of roads you enjoy driving the most and, of course, how much you want to spend. If you have money burning a hole in your pocket then there are many other things.
ig qednoir

Not really looking to go all out just enjoy driving it. It’s always good to hear from people going down a rabbit hole in their cars. I’ve done the same many times on other builds and I stopped enjoying it because I was focused on every sound it made. In my rs3 the worst thing I did was go catless downpipe. It stunk, was loud and drew too much attention. I should have stuck with basic bolt ons and and tune and left it there.
 
ig qednoir

Not really looking to go all out just enjoy driving it. It’s always good to hear from people going down a rabbit hole in their cars. I’ve done the same many times on other builds and I stopped enjoying it because I was focused on every sound it made. In my rs3 the worst thing I did was go catless downpipe. It stunk, was loud and drew too much attention. I should have stuck with basic bolt ons and and tune and left it there.
with that said, I do feel my NSX is exactly where I want it to be. It's as much a mental health/fun exercise when I tear it apart and put humpty dumpty back together
 
Wow! I had no idea you even got back into an NSX. Welcome back @serialNSXer !

I'm certainly not a tuner. I barely trust myself in front of a computer for my own stuff, but the hardware itself is stout and I stand by Adnan's kit even in hot/humid temps like FL. In terms of driveability nuances, i've gotten mine to be as "reliable" as my old CTSC kit. I'm on the AEM Infinity standalone. While it's far from my favorite, it's done pretty well so far. If money is no object, skip the AEM and go for something better though.

I'm adding Drive By Wire throttle actuators to my ASM ITB setup now. You can follow me on IG stories @ryumoto_ if you care. For your 2003 you'll need a DBW setup to limit the amount of rework. ITBs on any NSX is a bit of a project though but everything should be bolt-on affair by now.

With that said, I'd like to understand what you're looking to accomplish exactly. Is it just for sound? The ITBs are intoxicating at any RPM and the throttle response is crazy quick but to get the most out of it you should at least have a lightweight flywheel and a free flowing exhaust. Do you plan to keep the trumpets open or do plan to have a plenum built of some kind?

For me, there's no turning back. I'm an ITB NSXer for life. It's too good and really compliments how I built the car. If my car was relatively stock, would I do it? Probably not to be honest.
Got some DBW from A.S. Motorsport too and currently getting it tuned this weekend. Here is my setup for now.
 

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