I need to know so I can know how to do the mod if I ever choose to do so.
Any pics of the process would be greatly appreciated.

 

http://www.fc3spro.com/TECH/HOWTO/TBM/tbm.html
this is a good time to learn how to use the search button also.

 

I just did mine, mainly because I hated the coolant lines (or lack there of) that ran to it, works great. Still tweaking the idle perfect, but its worth it!

 

The main benifit of removing the secondary throttle plates is that your throttle response will be substantially improved. I've only done it on a TII, but people have said that the effect is less evident on a n/a. As for the coolant hose, take the upper intake manifold off a TII and you'll understand why people want to eliminate the 90 degree coolant hose.

 

yeah, that coolant line sucks ***!

I replaced it with one about 18" long so now it'll probably never be coming off again.

 

You remove the secondary throttle plates helping remove restrcitions which is suppose to give better top end flow.

You also get rid of the Thermowax/coolant lines there to remove HOT coolant from going near your intake track. Heat soak not good.

 

Considering the TII has more horsepower, of course the effects on an N/A will seem less substantial. But anyways...

This mod can lead to a bad idle.

 

Really bad idle. I'm STILL tryin to smooth mine out. Its a never ending battle.

 

I did this mod on my s4 na this past summer and saw NO performance gain from it. NONE. ZILCH. ZERO.


What I did notice was a whole lot more room around the tb, and it took less time to get the manifolds off when I was working on the car.

The end result. I've put the thermowax back on (and the cruise control, too) and used high pressure fuel hose to direct the coolant to and from it, but left everything else off. My engine continues to run the same without the BAC and Air Bypass Solenoid Valve, although I have cranked the idle up to 900 (from 750) to alleviate any sudden loads...


[edit] Guess I should mention that I'd already yanked the secondaries long before.

 

In the NA, you mainly get a slightly better throttle response (or, at least that's what I got). Probably only noticable on cars that had sticky secondary throttles anyway. I left the thermowax on and just removed the secodary throttle plates. I would find having to manually warm up my car VERY annoying. However, thermowax is now gone on my throttle body, since I can use the aux output on my Microtech to run the ASV valve. That way I still get the warmup function, but don't need to run a coolant line to the throttle body...