I m getting ready to remove the "Rats Nest" off the 88 S4 engine that I recently transplanted into my ongoing 85 GSL-SE project.

In the following link, it tells me to remove the double throttle butterfly plates. Is this correct, are these not your secondary throttle plates?

Does anyone recommend a better procedure? Or should I use this one?

http://www.rotaryresurrection.com/2n...s_removal.html

Thanks for your input!

 

Its OK to remove the plates, the only thing you need to do is plug the holes.

 

You don't have to do those modifications if you don't want, the main things are the vacuum lines. The throttle body is optional.

 

the double throttle system is just like on the GSL-SE. It's the No. 2 secondary butterflies, behind the front two. You don't need to pull them off. You can if you want to, just make sure it's sealed up. There is also a mechanical fast idle system ("thermowax") and a dashpot to reduce the chances of the engine stalling. Those can be removed but many people (such as myself) feel that hurts driveability. There are many similarities between the s3 and s4 13B 6 port engines. The ignition system is one of the biggest changes, as the s4 engine has true electronic spark advance while the s3 still has a dizzy with some solenoids just like the 12A.

The main rats nest on the s4 n/a consists of two air pump solenoids (switching and relief solenoids), a hot start solenoid (fuel pressure regulator control), and an EGR solenoid. None of those are needed if you are not concerned about emissions. They have no noticeable effect on driveability when removed.

 

Thottle body mod sounds like a good idea but I wish I never did it..

Really in na N/A there's no power gains by doin it

 

Thank you for all your replies! I now understand this better.

thanks.

 

Here is another how to:

http://fc3spro.com/TECH/HOWTO/TBM/tbm.html

there really isn't much power to be had, it just increased throttle response.