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[clawless]

Well this started because I was messing with the idle and A/F ratio and noticed the micro switches were not being engaged at idle or WOT. (What does the idle one do? Is seemed to make no difference when I click it?) I had planned to do this upgrade when I got my water/methanol injection system, with a dual stage boost controller. But I figured I could start here.

WOW what a difference. MUCH better throttle response and you can really feel the extra power, spools much faster. This won’t work on the series 2 turbo’s. I am not sure how big the intake port is on those, maybe worth switching? A good upgrade for the NA’s I am sure.

Sorry for the blurry pics, I did not have the camera on close up


The Audi throttle body is off of an '86 4000S I got it from ebay for about $30 delivered. It noticeably bigger and wider, but still has the same mounting/bolt pattern.




Before porting the intake I wanted to make sure this would all fit. You have to use the original throttle cable mount. It’s hard to get it off the old TB as its “crimped” on shaft. You have to work it off, and it’s tight getting on to the new TB. Make sure you don’t tighten the nut down too much as it will bind. The black piece that the Audi cable set in, it rotated before, it does not now. Its trapped by the throttle cable retainer on the intake. If you over tighten the nut on top it will bind on to that piece and it will not spring back to idle. Also checked the hood clearance, all was good.





The WOT switch mount that came with the new TB will not fit / clear the intake. I cut the switch mount off the bracket and drilled a hole in it to mount it on the throttle cable retainer. I cut the Audi wiring connector and spliced the switches into the original wiring.




The intake manifold needs to be ported. I used a rough bit I got in a set of four from home depot (~$7) sorry no good pic, i will try to post one. I used the new gasket (fel-pro #23623 $1.50 Advance Auto, ordered 3) to mark what had to be cut out. I used 2 oil soaked rages to protect the intake. Make sure you do not get ANY shaving in the intake. I vacuumed out the shavings first then cleaned any left over shavings up before I pulled the rags out, then vacuumed the intake again.



BEFORE


AFTER



Once ported, I put all back together. Since the Audi TB is not equally oval like the factory one and the factory connector hose was hard, I used an Injen 3 1/8” silicone connector, fiber reinforced (~$5 from Injen directly) This thing fits PERFECTLY! It’s flexible and makes up for the difference in sizes.





I screwed the idle screw all the way in and backed it out 2 turns. It fired right up, first try! I spent most of the day, taking my time, switching this out. Well worth the time.
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Clawless

'80 931 M471, Audi Throttle Body, 11PSI for now
'97 Volvo 850R (The other woman)

'85.5 944 SOLD - 175,000 mi most reliable car EVER
'79 924NA RIP