2nd gen turbo TID mod
89-91 shown. 87-88 will differ slightly
Defiantly one of the power restricters on the Turbo II's is the stock turbo inlet duct (TID). The pipe between the turbo and airflow meter. It has 2 90 degree bends in it to clear the airpump. There for this mod can only really be done if you have already removed the air pump. (Not recommended for street cars as it's illegal to remove emission stuff blah blah my legal statement :D)
Parts I used: all from the local
hardware store.
3" - 2" rubber reducer
3" rubber coupler
3" 45 degree bend ABS
a few inches of 3" ABS pipe
vacuum line nipple
I think most people use a 45 piece that is longer, but I couldn't find anything. I glued the straight piece into the 45 to make it longer. The 3"-2" reducer goes to the turbo, and the 3" one goes to the air flow flow meter. Not to hard :). I added the vacuum nipple for the line to the PCV. If you have an 89-91 your stock TID will have 2 vacuum lines. The 2nd one is for the stock boost controller. Mine is disabled as I'm running a manual controller so I only need the one. The other problem is if you have the stock bypass valve (or blow off valve) as that needs to be plumbed into the TID... I don't so no problem for me. You can't vent the stock one into the air or the car won't run or idle very well. You need a big one way check valve.
First step is to remove the stock intake and TID. If you still have the stock airbox on, you need to remove the 3 bolts that hold the airbox to the brackets, the 3 bolts that hold the airbox intake pipe to the top of your rad, then unscrew the clamp that holds the stock TID to the air flow meter (AFM). You should then be able to pull the whole airbox and AFM out of the TID and out of the way. Once it's out you can unplug the wires to the AFM
Now to remove the Stock TID. Pull out the vacuum line(s) and stock BOV if you have it. And undo the clamp holding it to the turbo, and it'll pull right off.
Now is a good time to check your turbo. You can grab the center of the turbo wheel and try to move it up/down. There shouldn't be much play if any.
There are 2 bolts on the bottom of the air box that hold the AFM on the 89-91's
Next clamp the New made TID onto the turbo. And clamp the AFM to the end. Plug in your vacuum lines that you need. You can notice the manual boost controller and lines in this pic. As well as the old air pump line to the ACV.
Stick your cone filter on the end of the AFM. (This mod doesn't work with the stock air box) You'll need an adapter plate for the 87-88 ones. For the 89+ you just need a cone with a 2.75" hole and it'll go straight on. Lastly build a bracket to hold the AFM in place.
As a last thought I added the one way check valve out of the stock TID for the PCV line.
