Audiboy ( or anyone) you ever measure the voltage at the CTS /TPS? I left my Fluke at the shop.

Dead · 04-03-2003, 05:06 PM

Do you know what the readings are closed and wide open? If not I'll check later(when I remember to bring the MM home.)

Rob K · 04-03-2003, 05:17 PM

Closed is around .65v, and I believe around 4.4v for WOT.

Audiboy · 04-03-2003, 06:38 PM

Dead · 04-03-2003, 07:03 PM

Dead · 04-03-2003, 07:03 PM

Audiboy · 04-03-2003, 09:30 PM

VAP · 04-04-2003, 01:15 AM

I drift this pin out and turn it down on the lathe. But since I don't have benefit of TPS I have to turn the stop pad down .0xx" to bore parallel using Starret Master Precision Squares.

On the 2.8 Twin bore TB the stock butterflies never open more than 85-90% when stock. With a little tweaking they can open a true 100%.

And I did flow the difference and have notes. At 95% open it flows 12.2% less than at 100% on the secondary venturi @400CFM. At 98% open it flows 9.25% less than 100%@400CFM. That is a number equal to the MAF screen. Every little bit helps.

And I would bet the single bore TB's would benefit a similar amount tho forced induction is a helluva equalizer.

a412banger · 04-04-2003, 07:10 AM

rtking · 04-04-2003, 11:08 PM

I have the ported throttle body from TAP (I got off ebay.) I never thought to check the butterfly position until after I read this thread!

As it turns out, my butterflies (at WOT) was not 100% open... maybe 95%. After adjusting the cable, all I can say is WOW! Throttle response is immediate and (based on the "butt-o-meter") the car feels faster!

OK 2 out of 3 done... now I need that Velocity Stack! ;-)

Bob K

Bob

VAP · 04-05-2003, 04:09 AM

Just because your throttle cable is now pulling your butterflies open until they contact the built-in stop does not mean the butterflies are 100% open. In fact I'm willing to bet the secondary butterfly is less than 95% open, probably closer to only 90% open (5-7 degrees of unused throttle butterfly rotation seems to be about average). Without modification to the throttle body there's no way you can adust that additional 5%-10% under-rotation out with just a cable adjustment.

In effect, if your 95% estimate is accurate there remains a 200%-300% net improvement over/above the improvement you're feeling now, as-yet untapped and remaining in the throttle body.

hehehe...yer welcum;-)

emil me on that other thing

04-03-2003, 05:17 PM	#2
Rob K AudiWorld Senior Member Garage is empty, add now Join Date: Mar 2000 Posts: 879	Re: Audiboy ( or anyone) you ever measure the voltage at the CTS /TPS? I left my Fluke at the shop. Closed is around .65v, and I believe around 4.4v for WOT. __________________ Coming soon 3.0 01E Tec-II EMS

04-03-2003, 06:38 PM	#3
Audiboy AudiWorld Super User Garage is empty, add now Join Date: Mar 2000 Posts: 13,204	I haven't but I adjusted the cable so I get 98% WOT compared to 87% before :)

04-03-2003, 07:03 PM	#4
Dead Elder Member Garage is empty, add now Join Date: Jul 2000 Posts: 23,171	A lot of cars have the same problem.

04-03-2003, 07:03 PM	#5
Dead Elder Member Garage is empty, add now Join Date: Jul 2000 Posts: 23,171	Thanks.

04-03-2003, 09:30 PM	#6
Audiboy AudiWorld Super User Garage is empty, add now Join Date: Mar 2000 Posts: 13,204	Yep, and it's only a simple cable adjustement.

Welcome to AudiWorld!
		Welcome to AudiWorld.com. You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join AudiWorld.com today!

04-04-2003, 01:15 AM	#7
VAP AudiWorld Super User Garage is empty, add now Join Date: Mar 2000 Posts: 13,990	There's also a "stop" pad that prevents over-travel. On the Stage 2+ thorttle body... I drift this pin out and turn it down on the lathe. But since I don't have benefit of TPS I have to turn the stop pad down .0xx" to bore parallel using Starret Master Precision Squares. On the 2.8 Twin bore TB the stock butterflies never open more than 85-90% when stock. With a little tweaking they can open a true 100%. And I did flow the difference and have notes. At 95% open it flows 12.2% less than at 100% on the secondary venturi @400CFM. At 98% open it flows 9.25% less than 100%@400CFM. That is a number equal to the MAF screen. Every little bit helps. And I would bet the single bore TB's would benefit a similar amount tho forced induction is a helluva equalizer.

04-04-2003, 07:10 AM	#8
a412banger New Member Garage is empty, add now Join Date: Jun 2002 Posts: 108	Dave - thanks for the email/link to the 12V site! __________________

04-04-2003, 11:08 PM	#9
rtking Junior Member Garage is empty, add now Join Date: Sep 2001 Posts: 877	You guys talked me into this! Thanks a bunch!!! I have the ported throttle body from TAP (I got off ebay.) I never thought to check the butterfly position until after I read this thread! As it turns out, my butterflies (at WOT) was not 100% open... maybe 95%. After adjusting the cable, all I can say is WOW! Throttle response is immediate and (based on the "butt-o-meter") the car feels faster! OK 2 out of 3 done... now I need that Velocity Stack! ;-) Bob K Bob

04-05-2003, 04:09 AM	#10
VAP AudiWorld Super User Garage is empty, add now Join Date: Mar 2000 Posts: 13,990	Now let me throw you another curve... Just because your throttle cable is now pulling your butterflies open until they contact the built-in stop does not mean the butterflies are 100% open. In fact I'm willing to bet the secondary butterfly is less than 95% open, probably closer to only 90% open (5-7 degrees of unused throttle butterfly rotation seems to be about average). Without modification to the throttle body there's no way you can adust that additional 5%-10% under-rotation out with just a cable adjustment. In effect, if your 95% estimate is accurate there remains a 200%-300% net improvement over/above the improvement you're feeling now, as-yet untapped and remaining in the throttle body. hehehe...yer welcum;-) emil me on that other thing

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

04-05-2003, 04:09 AM
AudiWorld Audi R8 Paid Advertisement