Lago Blue

<center><img src="http://pictureposter.audiworld.com/124134/tubular_bells.jpg"></center><p>
...the effective (w)hole is greater than the $um of its' parts.

<u>Intro &amp; Overview:</u>

Regarding a '93 90Q, here are 21 maintenance &amp; mod. items which may collectively boost mileage &amp; torque. Or they may not!

I am going to illustrate some items that may not usually be considered part of the Intake System because I find them useful when considering the Intake as a whole system. Taking several simple steps towards amongst other things, "tubular bells" (see above). A more efficient &amp; low cost system is my goal.

I will attempt to expand each topic below in this thread as time permits. I invite you to check back here &amp; welcome your comments &amp; questions. I have questions of my own that perhaps you can help me with.

Certainly, many of these ideas are not new, nor mine, but I've included them as I like them. I'll finish as time permits.

Topics:

1. Grill;
2. Scoop;
3. Bucket;
4. Filter-box Mounts;
5. Bucket to Filter-box seal;
6. Filter-box Snorkel;
7. Filter-box Lid Clamps;
8. Filter-box Exit V-stack (Mance's Mk. I);
9. "Restrictor-Plate" MAF;
10. OEM Noise Damper;
11. New OEM Rubber Gasket &amp; Telephone Cord Fix;
12. Non-"S" T/B;
13. T/B to I/M OEM Gasket, Synthetic Seal;
14. Intake Manifold, why & how:
a.) what to do, in order of importance:
-1. Vacuum
see why: http://search.audiworld.com/showthre...ght=over+again
see how: http://search.audiworld.com/showthread.php?t=2594462
-2. EGR Passage
-3. while your there, Valley Pan; & more...:
b.) VAP's I/M Workshop; see: http://www.12v.org/audi/imworkshop/
15. Injector Re-cycle;
16. Injector Spray;
17. Vac. Lines &amp; FPR; (see link re: "excessive fueling": [/url])http://www.interworldna.com/pico/aut..._actuators.php
18. EGR Solenoid;
19. Cam Cover Vents &amp; Hoses;
20. O2 Sensors; &amp;
21. Odo/Tripmeter &amp; Trip Computer;

Organizing the Work: &amp;

Conclusion: I will tell you straight away that I am very satisfied with the results of all of this, as the car runs better (faster, smoother &amp; more economically) than I thought possible. More to follow.<ul><li><a href="http://tubular.net/covers/large/TubularBells.jpg">Tubular Bells</a></li></ul> (this is the music I'm reminded of by the noise generated when doing the port-work of the Intake Manifold Workshop with abrasive paper spinning on the end of a high-speed mandrel...)

Sorry, since "The Change" the topics I've completed no longer appear in numerical order.

Luxus Panzer

Keeping a eye on this one.

quattro90S6

<center><img src="http://pictureposter.audiworld.com/46176/2005-05-25_002.jpg"></center><p>
but it ran the best it ever has after doing these, mostly not engine performance modifications, and the phone cord was one. Before i did it i mind as well not had a gasket there, but that nice new snug fit with a snap even! It's that job well done feeling....

...then my brother hit a crub and i havent driven my car in years

quattro90S6

b/c why, now 3 years ago, would i have put a stock tb back on when i had two others that were worked on? Hmmm...

Anarchy_4play

What is the telephone cord fix?

EDIGREG

Using RJ11 cable to better seal the stock plenum to the throttle body.

Anarchy_4play

oh thats cool.

quattrokid98A4

off topic* Did you fix ur a4 up from a wreck?

Lago Blue

<center><img src="http://pictureposter.audiworld.com/50038/plenum_to_tb.jpg"></center><p>
...fits into the "backside" of the OEM T/B Seal, shown above.

This fix allows the above seal to better ensure no un-metered air leak occurs between the OEM Noise Damper &amp; the T/B by enlarging the circumference of the seal. Ensure that the seal is in good condition. Over time, they degrade due to heat exposure &amp; will tear when you try to remove them from the T/B.

Get used to using the search function, alot. See also original write-up here:

https://forums.audiworld.com/a4/msgs/1560129.phtml

Please pay attention the the 45° angle Mance talks about in the thread below, as I want to use this same idea to do a fix on the Air Filter-box.<ul><li><a href="https://forums.audiworld.com/12v/msgs/3337.phtml">2nd paragraph here...</a></li></ul>

Lago Blue

<center><img src="http://pictureposter.audiworld.com/124134/v_stack_6_trial_fit.jpg"></center><p>
...It was not without some trepidation that I did this mod, as at the time IIRC, Mance was not making any more. That may have since changed, or not? In order to do this, I had to hammer (a great deal) on one of Mance's lovely &amp; rare creations (Gasp!). That I was successful, I am relieved, but be warned, if you try this, you may not be! It also took a long time to do.

My 2nd-hand V-Stack (Mk 1?) came w/o instructions &amp; may have originally been designed for some other application, the A4 perhaps?

I thought I could improve the fit, the method of mounting &amp; its' function here as follows:

a.) Increase the base (outlet) outside diameter to permit a different way of re-mounting the stack directly into B4 MAF screen recess/counter-bore. This, in turn is going to allow a step-less transition from inside the stack into the main MAF I.D.);

b.) Curve the straight tapered walls such that they have a more parabolic profile; &amp;

c.) Reverse bell-curve the inlet.

The main purpose of all of the above is not just that, perhaps if only theoretically, these changes might each allow a little more flow. Emphasis on <i>might</i>, as I only hope so. Perhaps someone with the required equipment could measure any change? I'd love to know. I really did it to try to get <i>smoother</i> flow, which especially at low speeds, is what I want the sensor to "see"; and because this; was fun.

<u>1st photo:</u> The Before Shot.
An as delivered VAP V-stack installed (borrowed this shot from someone here, thanks BTW). IIRC Mance made a couple of versions, but this is how my 2nd hand one looked to start with.

Note:
- how there is a step between the stack outlet &amp; the MAF I.D.;
- the tapered walls are conical, not curved &amp; all the change from parallel walls to tapered walls occurs in one place; &amp;
- the inlet ring is flat/horizontal.

<u>2nd photo:</U> Partially Mod'd. V-stack Installed Trial Fit.
Almost but not quite step-less transition to MAF I.D. at this stage; curved walls; &amp; reverse curved belled inlet. This was just a trial fit &amp; much more hand work was required to take it from looking a bit like a 50's minature hammered ice bucket, back to something more presentable.

The outlet length of the stack is long enough; &amp; the I.D. of the air-box lid outlet is big enough, that the stack now passes clear through the lid &amp; nests perfectly into the MAF screens counter-bore. Eliminated from the air stream are the steps/transitions for the V-stack outlet; the cork gasket; the screen circ-lip groove; &amp; main MAF I.D. (I realized when I saw photo 1 that I had never mounted my V-stack as well as this one was; I put the wraps of tape on the very bottom of the stack &amp; fitted it into the lid, but not through! In STFA, I had found this thread: Posted by Hokie_90 on 2003-06-27 13:53:14 re: electrical tape: "I wrapped it around 5 times, ½ up from the bottom of the base". Ah-hah!

<u>3nd photo:</U> Where the stack now mounts:
If you where late to the MAF party like me, in STFA you may recall the phrase "leave the MAF screen lip in place". I have no idea why this was, but now I'm using that spot to mount the V-stack.
The stack base O.D. is now larger (approx. 3 &amp; 1/16") &amp; a tight interference fit into the OEM counter-bore cut for the discarded MAF screen &amp; butts up against the step itself. The stack clicks into place (a very satisfying sound!) with a little twist &amp; even with a tiny smear of anti-seize is held in very firmly (supporting the stack with just one finger under the lip, it hung &amp; held the weight of the air-box lid, MAF, flex hose, my trouble light &amp; the plenum w/vent hoses while I tried to take a picture!). No more 5 wraps of electrical tape!

<u>4th photo:</u> How to Curve the Walls.
Do this before the rim. Clean the pipe first. Note the wood under the pipe. Started with a 2 &amp; 3/8 O.D. pipe &amp; moved up to a 2 &amp; 7/8" when able. File &amp; polish your hammer-face. Check the fit frequently (you will need a few breaks!). The stack outer surface gets pretty ugly during this part but should remain pretty on the inside if you do this right, which is: only strike the stack where it is touching the pipe. It all cleans up v. nicely afterwards with a little hand sanding. Adjust the fit &amp; make the base circumference round &amp; the edge flat &amp; square (sand &amp; file) when you're done.

<u>5th photo:</u> "Rrroll Back the Rrrim" (don't ask, it's a Canuck thing).
Yes, I did get the idea to do this part from looking at the rim of my own Mk 1 V-stack, made from a large "Timmy's" paper coffee cup (it worked!). That I was able to de-screen w/only a modified paper coffe cup reminds me that I should mention I have the diminutive OEM MAF &amp; perhaps it is less sensitive than the larger ones to de-screening?

What I wanted to do here was encourage the air from the sides &amp; behind the entrance lip of the stack to get sucked in.

It was surprising how hard I could hit the thing (&amp; had to!) with a carefully polished ball-peen face hammer (and how long it took!). After reading of Mance's process here...

https://forums.audiworld.com/12v/msgs/64894.phtml

...I'm surprised it didn't split! Obviously I wouldn't recommend my process unless you could afford to ruin yours.

Do this sitting down. Note the wood underneath. Start by sanding the square edges on the outer lip round to help prevent any stress cracks from starting on the edge &amp; then start hammering carefully round &amp; round the rim.

<u>6th photo:</u> (shown above) Getting There.
This shows the fit into the counter-bore; the curved walls before sanding; the reverse curved bell-mouth; &amp; the almost smooth transition to the main MAF I.D.

<u>7th photo:</u> Purposely Installed w/Filter-box Flat Out of Position.
Very near the level of fit &amp; finish I wanted now.

I temporarily mounted the stack like this to show that I could here employ a stack that did not have the "flat" edge cut off its' perimeter. However, would I have been successful in rolling back the rim if there had been no flat? Perhaps not.

Lucky for me, my only regret is that during one of the trial fits, I broke a rib inside the lid w/my mallet tapping the still to tight fitting stack into place.

Cheers, David.