View Full Version : Some installation notes about the latest batch of SXTB+ throttle bodies...


VAP
05-21-2008, 06:22 AM
1. If I received STB's from you with auto transmission kick-down passing gear micro-switches then those TB's were returned with switches installed and calibrated here. If your car is a manual transmission remove the switch & harness assembly via the 2 phillips machine screws that attach the micro-switch mounting bracket to the throttle body.

2. All TPS's (throttle position sensors) are also calibrated to the butterflies here before shipping. Do NOT attempt to loosen the two stainless steel 2.5mm button head machine screws holding the TPS to the throttle body or adjust the TPS. "Code city" and a VERY poor running engine "if" you can even get it started requiring TB removal and complete TPS re-calibration if you disregard this!

3. During installation unplug the negative terminal of your battery cable to reset the ECU and leave it unplugged until installation is complete. MAKE SURE YOU HAVE YOUR RADIO SECURITY CODE TO GET IT OUT OF SAFE MODE BEFORE ATTEMPTING THIS!! If you don't have your radio security code and/or cannot get it from the dealer then leave both battery terminals connected and allow your ECU to re-learn on it's own. Takes a bit longer for the ECU to re-learn about the SXTB+ but otherwise less of a problem than having a non-functional radio stuck in "SAFE" mode.

4. After installation make sure your TB butterflies open fully via the go-pedal (not by hand). "Fully" in this case means all the way until the butterflies contact their built-in "stop". Fully 10% of EVERY TB I've ever looked at on these cars has the cable mis-adjusted so that the accelerator pedal cannot open the butterflies fully. This happens as a result of cable "stretch" over the years and by mechanics and others being less than careful reattaching the cable after removing it for whatever reason. Using the cable adjuster mechanism make sure that when someone pushing the accelerator pedal from inside the car can open butterflies fully. Adjust throttle cable so it stops at a point VERY slightly "beyond" fully opened butterflies (WOT). Do NOT "over-adjust" or you risk bending the throttle cable adjustment bracket that locks the cable in place! The new TB won't change any settings so if your cable is mis-adjusted with the SXTB+ it was mis-adjusted before with your old TB. Out of this order of SXTB+ throttle bodies there WILL be "statistically" 2.9 throttle bodies that WILL require adjustment to achieve full "lock-to-lock" WOT. On cars with auto transmissions make sure your cable is adjusted so that you have enough "over-travel" cable-length to achieve kick-down switch engagement once your WOT adjustment is achieved. You can determine this via an audible "click" of that switch when pressing "hard" on the accelerator tho you should have a person "in the car" pressing the go-pedal while you listen for the audible "click" near the TB as you cannot hear it from inside the car. All STB's have a "over-travel" designed into their cable pulleys. Using one on a manual transmission car you can adjust your cable-travel to stop at the WOT position. The auto cars use this over-travel for their "kick-down/passing gear" transmission activation which occurs "after/beyond" WOT and MUST leave this over-travel in their cable adjustment for proper micro-switch activation.

5. All TB's shipped from here have high-temp silicone caps over their vacuum ports as additional protection during shipment. The large one should be removed and the small one in base of TB can be removed or left in place depending on if you want to use it as-designed. It clogs very quickly on high mileage cars and serves no purpose on cars running silicone hose kits with recovery sleeves.

Every US SXTB+ "should" be in the hands of it's owner by now or at its designated "ship to" address. Canadian TBs sent Express Mail "should" be there early next week with "regular mail" Canadian units arriving week after next.

Enjoy! And if you have any questions, I'll be right over here playing catch-up on vintage Audi suspension parts.

odelay12v
05-21-2008, 09:45 AM
i had was about to search for install instructions but you just gave them to me! sweet! Thanks.. Really been enjoying the maf also so far! now just about everything else is ready to roll!

DaveInSaltLake
05-21-2008, 03:02 PM

EDIGREG
05-21-2008, 03:18 PM

DaveInSaltLake
05-21-2008, 03:40 PM
<img src="http://i47.photobucket.com/albums/f174/DavesData2/SXTB%20plus/DSCN5930.jpg" border="0" alt="Photobucket">

<img src="http://i47.photobucket.com/albums/f174/DavesData2/SXTB%20plus/DSCN5934.jpg" border="0" alt="Photobucket">

<img src="http://i47.photobucket.com/albums/f174/DavesData2/SXTB%20plus/DSCN5935.jpg" border="0" alt="Photobucket">

<img src="http://i47.photobucket.com/albums/f174/DavesData2/SXTB%20plus/DSCN5932.jpg" border="0" alt="Photobucket">

And a photo from Edigreg's archive for comparison:
<img src="http://edsaudi12v.com/audi/mance_xtb_sxtb.jpg" border="0" alt="Photobucket">

EDIGREG
05-21-2008, 04:07 PM
<a href="http://edsaudi12v.com/audi/xtbprocess/">http://edsaudi12v.com/audi/xtbprocess/</a>

VAP
05-21-2008, 04:28 PM
Now go install that bad boy immediately... time's a-wastin'!! ;-)

EDIGREG
05-21-2008, 04:59 PM
Rebuilding the heads and installing some headers should help a lot...but right now, I hardly use WOT because this TB flows so damn well that the rest of my motor can't keep up (yet!).

VAP
05-21-2008, 05:23 PM
over 300 degrees of cam duration at .500+" lift at/or about 8,000 RPMs to even begin to create a flow depression thru-the-butterflies.

EDIGREG
05-21-2008, 05:38 PM
By rebuilding, I meant that I will be fully modifying the heads with bigger valves, lightweight parts, the whole sha-bang. I understand how that could easily be interpreted as rebuilding to stock specs.

Regardless, I doubt I'll ever run 8k RPMs, but if I never have to buy another 12v TB in my life, I'd consider it mission accomplished. That's why we pay for the best of the best!

odelay12v
05-22-2008, 06:09 AM

VAP
05-22-2008, 06:20 AM
with a sub 280* street/dual purpose camshaft cannot burden or tax the STB flow rates. That unless you were running a pair of cams with solid (non-hydraulic) lifters and over 300 degrees duration PLUS over .500"/12.7mm of valve lift at 8k RPM's you still couldn't pull enough air thru the S+ throttle body to even begin to approach it's capabilities. And the 12V engine would be a LOT of things with those kinds of cam profiles at that point but I wouldn't count "daily driver" among them as it wouldn't idle under 1,500RPMs, wouldn't breathe until well-above 4k RPMs, would have to abuse the clutch to get away from a dead-stop and stand-alone would be the only way to control it. Basically a $15-$20k engine build as you'd want a LOT of other stronger bottom-end componentry and light-weight upper reciprocating/rotating internals with an engine "that" cam'd up ;-)

But when/if you are ever able to exceed this TB's potential there's always the RSXTB that raises the bar another 25-30%.

VAP
05-22-2008, 06:23 AM

odelay12v
05-22-2008, 08:10 AM

EDIGREG
05-22-2008, 09:20 AM

EDIGREG
05-22-2008, 09:23 AM
My plan at the moment is the above-mentioned items and stand-alone...good to know I won't need another TB upgrade. ;]