Downforce air intake is intake scoop EU version NSX NA2 different??

[rsevo6]

I just started to install a Downforce air intake scoop on my '98 Na2.

When taking the OE scoop out, I found it to have a vacuum operated valve in the scoop opening, unlike any of the US OE versions that I have seen.

This vacuum line comes from a magnetically operated valve ("ansaugsteuer magnetventil"), which in turn comes from a control box "steuermodul" (number7 vacuum line in the last pic) , see pics below from german manual that I have.

The system is according to the manual new on the EU '97-on model (only for 6-speed model/non-auto) and is called "intake air control system on C32B2 engine"

Anyone know if this is a difference on a Euro spec NSX Na2 compared to a US spec NSX Na2??

Can I delete this air intake valve and plug the vacuum line without messing up the fueling, A/F ratio?
Please excuse the big pics, possibly a moderator can resize them?

the vacuum line (in centre top of pic)

overview with vacuum line

OE intake scoop with vacuum pot

The vacuum operated air intake valve

Pic from the manual of magnetic control valve "ansaugsteuer magnetventil" (at pen point)

Pic from the manual of control box "steuermodul" with number7 vacuum line leading to the valve

 

[TOOLTIME]

Your Nsx is special. My 04 doesn't have that.

 

[OneRedNSX]

I would highly doubt that they would have taken the time / effort / money to retune the entire car's fuel tables to correspond with that valve. I could be wrong, but even so, removing it couldn't do anything worse to mess up the values than say adding a better intake.

 

[rsevo6]

All the parts are listed and can be found in my workshop manual as factory change on the EU spec '97-on manual shift NSX.
As no one here seems to know of these parts, I have to conclude this must be a difference between EU spec NSX and US spec NSX :frown:

I have encountered something like this before on my other car, a '99 Mazda 10th AE MX-5 (Miata). This car was sold in a limited edition special spec in several countries all over the world and although there were small equipment differences between JP/EU/US, it was thought mechanically to be the same car all over the world.
It turned out it wasn't.

After buying the Miata new, within 3 months I ordered a FM turbokit from the US.
While fitting it, it turned out that several parts on my EU car were different from the US spec car for which the turbokit was made.
Luckily these were only minor things and could be remidied by modifying a few parts and fitting one US spec OE part that the Turbokit vendor as a fast remidy took off one of his own cars and sent me free of charge as I was in a hurry to finish the car.

Now finding differences on my NSX does make me wonder what other problems/differences EU vs US spec I may encounter when I start installing my '97-on Comptech supercharger kit that I bought some time ago as this is also designed for the US spec NSX.:frown:

I do hope there won't be any big differences making the install on my EU NSX a problem.

For now, I have decided to re-install the OE airscoop with it's valve and put the DF scoop back in the box.

Working up to the CTSC install, I will soon first permantly install monitoring equipment on the car for measuring wideband A/F, knock, Map/boost, etc so I will be able to monitor all changes when fitting the CTSC.
I think that when the monitoring equipment is installed, before starting with the CTSC, I will test what the intake air valve does by blocking the vacuum line to it and see what this will do to my A/F and how this will influence the engine running.

 

[AR]

I encountered that ages ago when I did my first NSX. No worries mate, remove with impunity and plug away!

 

[AR]

Is here:

http://www.nsxprime.com/forums/showthread.php?t=56824&highlight=intake

A couple of UK NSX 3.2 owners that have gone the scoop way have also encountered this. It is probably to do with noise regulations.

Cheers,

AR

 

[rsevo6]

AR,
This is great info m8te, thanks a lot.
Good to know I am not the first to encounter this.
So these parts are just to reduce intake noise wow, lot of expensive stuff for such an unimportant function as most of us are spending cash to make MORE noise instead of less:wink:

I have exactly the same intake spaceage didgeridoo intake pipes:biggrin: , so is a EU spec thing.

So this may be one of the reasons the NSX is SOO much more expensive here than in the US: we have a lot more special parts on it:biggrin:
(here in Holland, the NSX stickerprice was $172.000-$178.000 as compared to $85.000-$90.000 in the US)

As I 've put everything back now, I will leave it on till I install my monitoring gauges and will see what/if it shows both with and without the valve connected to vacuum, just curious now.

Still a bit uneasy now however, on what other differences I may encounter when putting on the CTSC:frown: