Throttle Response
Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,706
Likes: 5
From: Toronto Ontario
Throttle Response
I've got an 02 A4 with 2.73's and I usually drive with my Active Handling on. It gives me slight bit of wheel spin which is usually enough to satisfy my needs. I turned the AH off recently after start up and noticed that the throttle response was not as good as when I turn the AH back on. I have try a few time afterward too to discover the same thing. I just wondered if this is a common thing with the C5?
Thanks
Thanks
Burning Brakes
Joined: Feb 2007
Posts: 1,211
Likes: 4
From: Vancouver B.C.
I asked the following question some time ago and got this answer from Chuck Cow, a noted tuner on the East Coast. I would probably get a tune from him If I didn't have to ship my PCM and EBCM to him. Here's the thread and an excerpt:
http://forums.corvetteforum.com/show...post1565327898
Quote:
Originally Posted by jornahow View Post
I wonder if anyone else with a C5 automatic has noticed this?
I have an 02 A4 coupe. When I put it into competition mode it seems like the throttle sensitivity decreases - I have to put my foot further into it to get the same response as I would when traction control is full on. Is it just me, or is there some programming in the ECU that kicks in to change throttle action to keep you from shredding tires in competition mode?
I would also like to hear from A4 owners who have had a tune without a torque converter change: who did your tune? What do you think of the outcome? Did you eliminate torque management or just modify it? Did you get changes to shift points, anything else you can think of and what about a transmission kit such as Transgo - results, recommendations. All knowledgeable input gratefully received.
The following is Chuck Cow's response:
Here's how it works......C5 and C6 Corvettes have an electronic throttle....On C5's there's a "throttle actuator controller' or "TAC MODULE" and C6's have the "TAC" module built into the ECM as one of the 3 internal processors.....
Due largely in part to the incredible performance of the lightning fast electronic throttle and the LSx series of engines incredible low end torque, the throttle has to be "curved" so that it isn't too responsive...#1) cause you could break parts and #2) cause you could EASILY spin the tires causing a VERY unsafe condition.
If you are driving a car with a CABLE throttle, the engine's response to the manual throttle cable or pedal is "linear" meaning that 5% throttle using your foot equals 5% throttle body opening and that 100% (floored) throttle is roughly equal to WOT or 100% throttle body opening. Hence they are about the same and more importantly, LINEAR.
Welcome to ELECTRONIC THROTTLE. When your foot is at 25% of the way into the throttle the engine's throttle blade is about 3.1% open! and at 50% throttle of foot travel, the engine's throttle is about 15.1% open!
The throttle is especially curved in the "below 50%" area and dosen't begin to get more "natural or linear" till above that point. Below 50% it is horrendous which causes unwanted side effects with respect to how GM tuned the cars originally (especially with automatics).
Unfortunately, most tuners can't or don't address this. ALL of my LS1/LS6 tunes have corrected this problem while maintaining a smooth throttle transition.
The problem is that with LS2/LS3/LS7 controllers, NOBODY can fix it.....yet. Until now, I'm the only guy that has ever even seen it for the LS2 family of controllers. I was testing it for a time for one of the companies, but while I got it working....it also caused problems and was unreliable.TRUST ME THOUGH.....I'M RIDING THEM TO CONTINUE WORKING ON IT.
As an example....The 06 and later ZO6 (due to it's huge power) has a MUCH MORE SUBDUED throttle than LS2's of the same year and for all controllers and vehicles (believe this or not!) When you decide to "GET ON IT" with the car in "competitive mode" (thinking that you're "getting on it") the throttle response curve is DISGUSTINGLY more conservative than in normal mode....HOW STUPID IS THAT????
Trust me, I'm the "GM ELECTRONIC THROTTLE SCIENTIST" and have spent zillions of hours messing with the system... While I'm still at it....it will be a while before it's working.....it if happens.
Realize the disaster and troubles if "just once" a GM electronic throttle stuck open....For this reason there are dozens of redundant safety checks which have delayed the release of this very powerful tuning feature for LS2 family controllers.
Also realize that some of what you are feeling is also "torque management" if it's not turned off...
I'm on your side and I'm still at it... WE NEED THIS FEATURE...but, PLEASE be patient.
This has been a public service announcement from:
CHUCK COW
http://forums.corvetteforum.com/show...post1565327898
Quote:
Originally Posted by jornahow View Post
I wonder if anyone else with a C5 automatic has noticed this?
I have an 02 A4 coupe. When I put it into competition mode it seems like the throttle sensitivity decreases - I have to put my foot further into it to get the same response as I would when traction control is full on. Is it just me, or is there some programming in the ECU that kicks in to change throttle action to keep you from shredding tires in competition mode?
I would also like to hear from A4 owners who have had a tune without a torque converter change: who did your tune? What do you think of the outcome? Did you eliminate torque management or just modify it? Did you get changes to shift points, anything else you can think of and what about a transmission kit such as Transgo - results, recommendations. All knowledgeable input gratefully received.
The following is Chuck Cow's response:
Here's how it works......C5 and C6 Corvettes have an electronic throttle....On C5's there's a "throttle actuator controller' or "TAC MODULE" and C6's have the "TAC" module built into the ECM as one of the 3 internal processors.....
Due largely in part to the incredible performance of the lightning fast electronic throttle and the LSx series of engines incredible low end torque, the throttle has to be "curved" so that it isn't too responsive...#1) cause you could break parts and #2) cause you could EASILY spin the tires causing a VERY unsafe condition.
If you are driving a car with a CABLE throttle, the engine's response to the manual throttle cable or pedal is "linear" meaning that 5% throttle using your foot equals 5% throttle body opening and that 100% (floored) throttle is roughly equal to WOT or 100% throttle body opening. Hence they are about the same and more importantly, LINEAR.
Welcome to ELECTRONIC THROTTLE. When your foot is at 25% of the way into the throttle the engine's throttle blade is about 3.1% open! and at 50% throttle of foot travel, the engine's throttle is about 15.1% open!
The throttle is especially curved in the "below 50%" area and dosen't begin to get more "natural or linear" till above that point. Below 50% it is horrendous which causes unwanted side effects with respect to how GM tuned the cars originally (especially with automatics).
Unfortunately, most tuners can't or don't address this. ALL of my LS1/LS6 tunes have corrected this problem while maintaining a smooth throttle transition.
The problem is that with LS2/LS3/LS7 controllers, NOBODY can fix it.....yet. Until now, I'm the only guy that has ever even seen it for the LS2 family of controllers. I was testing it for a time for one of the companies, but while I got it working....it also caused problems and was unreliable.TRUST ME THOUGH.....I'M RIDING THEM TO CONTINUE WORKING ON IT.
As an example....The 06 and later ZO6 (due to it's huge power) has a MUCH MORE SUBDUED throttle than LS2's of the same year and for all controllers and vehicles (believe this or not!) When you decide to "GET ON IT" with the car in "competitive mode" (thinking that you're "getting on it") the throttle response curve is DISGUSTINGLY more conservative than in normal mode....HOW STUPID IS THAT????
Trust me, I'm the "GM ELECTRONIC THROTTLE SCIENTIST" and have spent zillions of hours messing with the system... While I'm still at it....it will be a while before it's working.....it if happens.
Realize the disaster and troubles if "just once" a GM electronic throttle stuck open....For this reason there are dozens of redundant safety checks which have delayed the release of this very powerful tuning feature for LS2 family controllers.
Also realize that some of what you are feeling is also "torque management" if it's not turned off...
I'm on your side and I'm still at it... WE NEED THIS FEATURE...but, PLEASE be patient.
This has been a public service announcement from:
CHUCK COW
Last edited by jornahow; Aug 20, 2008 at 01:03 AM.
Premium Supporting Vendor
Joined: Oct 2004
Posts: 36,838
Likes: 438
From: Manassas Park VA
St. Jude Donor '07-'08,-'13-'14, '16-'17
I asked the following question some time ago and got this answer from Chuck Cow, a noted tuner on the East Coast. I would probably get a tune from him If I didn't have to ship my PCM and EBCM to him. Here's the thread and an excerpt:
http://forums.corvetteforum.com/show...post1565327898
Quote:
Originally Posted by jornahow View Post
I wonder if anyone else with a C5 automatic has noticed this?
I have an 02 A4 coupe. When I put it into competition mode it seems like the throttle sensitivity decreases - I have to put my foot further into it to get the same response as I would when traction control is full on. Is it just me, or is there some programming in the ECU that kicks in to change throttle action to keep you from shredding tires in competition mode?
I would also like to hear from A4 owners who have had a tune without a torque converter change: who did your tune? What do you think of the outcome? Did you eliminate torque management or just modify it? Did you get changes to shift points, anything else you can think of and what about a transmission kit such as Transgo - results, recommendations. All knowledgeable input gratefully received.
The following is Chuck Cow's response:
Here's how it works......C5 and C6 Corvettes have an electronic throttle....On C5's there's a "throttle actuator controller' or "TAC MODULE" and C6's have the "TAC" module built into the ECM as one of the 3 internal processors.....
Due largely in part to the incredible performance of the lightning fast electronic throttle and the LSx series of engines incredible low end torque, the throttle has to be "curved" so that it isn't too responsive...#1) cause you could break parts and #2) cause you could EASILY spin the tires causing a VERY unsafe condition.
If you are driving a car with a CABLE throttle, the engine's response to the manual throttle cable or pedal is "linear" meaning that 5% throttle using your foot equals 5% throttle body opening and that 100% (floored) throttle is roughly equal to WOT or 100% throttle body opening. Hence they are about the same and more importantly, LINEAR.
Welcome to ELECTRONIC THROTTLE. When your foot is at 25% of the way into the throttle the engine's throttle blade is about 3.1% open! and at 50% throttle of foot travel, the engine's throttle is about 15.1% open!
The throttle is especially curved in the "below 50%" area and dosen't begin to get more "natural or linear" till above that point. Below 50% it is horrendous which causes unwanted side effects with respect to how GM tuned the cars originally (especially with automatics).
Unfortunately, most tuners can't or don't address this. ALL of my LS1/LS6 tunes have corrected this problem while maintaining a smooth throttle transition.
The problem is that with LS2/LS3/LS7 controllers, NOBODY can fix it.....yet. Until now, I'm the only guy that has ever even seen it for the LS2 family of controllers. I was testing it for a time for one of the companies, but while I got it working....it also caused problems and was unreliable.TRUST ME THOUGH.....I'M RIDING THEM TO CONTINUE WORKING ON IT.
As an example....The 06 and later ZO6 (due to it's huge power) has a MUCH MORE SUBDUED throttle than LS2's of the same year and for all controllers and vehicles (believe this or not!) When you decide to "GET ON IT" with the car in "competitive mode" (thinking that you're "getting on it") the throttle response curve is DISGUSTINGLY more conservative than in normal mode....HOW STUPID IS THAT????
Trust me, I'm the "GM ELECTRONIC THROTTLE SCIENTIST" and have spent zillions of hours messing with the system... While I'm still at it....it will be a while before it's working.....it if happens.
Realize the disaster and troubles if "just once" a GM electronic throttle stuck open....For this reason there are dozens of redundant safety checks which have delayed the release of this very powerful tuning feature for LS2 family controllers.
Also realize that some of what you are feeling is also "torque management" if it's not turned off...
I'm on your side and I'm still at it... WE NEED THIS FEATURE...but, PLEASE be patient.
This has been a public service announcement from:
CHUCK COW
http://forums.corvetteforum.com/show...post1565327898
Quote:
Originally Posted by jornahow View Post
I wonder if anyone else with a C5 automatic has noticed this?
I have an 02 A4 coupe. When I put it into competition mode it seems like the throttle sensitivity decreases - I have to put my foot further into it to get the same response as I would when traction control is full on. Is it just me, or is there some programming in the ECU that kicks in to change throttle action to keep you from shredding tires in competition mode?
I would also like to hear from A4 owners who have had a tune without a torque converter change: who did your tune? What do you think of the outcome? Did you eliminate torque management or just modify it? Did you get changes to shift points, anything else you can think of and what about a transmission kit such as Transgo - results, recommendations. All knowledgeable input gratefully received.
The following is Chuck Cow's response:
Here's how it works......C5 and C6 Corvettes have an electronic throttle....On C5's there's a "throttle actuator controller' or "TAC MODULE" and C6's have the "TAC" module built into the ECM as one of the 3 internal processors.....
Due largely in part to the incredible performance of the lightning fast electronic throttle and the LSx series of engines incredible low end torque, the throttle has to be "curved" so that it isn't too responsive...#1) cause you could break parts and #2) cause you could EASILY spin the tires causing a VERY unsafe condition.
If you are driving a car with a CABLE throttle, the engine's response to the manual throttle cable or pedal is "linear" meaning that 5% throttle using your foot equals 5% throttle body opening and that 100% (floored) throttle is roughly equal to WOT or 100% throttle body opening. Hence they are about the same and more importantly, LINEAR.
Welcome to ELECTRONIC THROTTLE. When your foot is at 25% of the way into the throttle the engine's throttle blade is about 3.1% open! and at 50% throttle of foot travel, the engine's throttle is about 15.1% open!
The throttle is especially curved in the "below 50%" area and dosen't begin to get more "natural or linear" till above that point. Below 50% it is horrendous which causes unwanted side effects with respect to how GM tuned the cars originally (especially with automatics).
Unfortunately, most tuners can't or don't address this. ALL of my LS1/LS6 tunes have corrected this problem while maintaining a smooth throttle transition.
The problem is that with LS2/LS3/LS7 controllers, NOBODY can fix it.....yet. Until now, I'm the only guy that has ever even seen it for the LS2 family of controllers. I was testing it for a time for one of the companies, but while I got it working....it also caused problems and was unreliable.TRUST ME THOUGH.....I'M RIDING THEM TO CONTINUE WORKING ON IT.
As an example....The 06 and later ZO6 (due to it's huge power) has a MUCH MORE SUBDUED throttle than LS2's of the same year and for all controllers and vehicles (believe this or not!) When you decide to "GET ON IT" with the car in "competitive mode" (thinking that you're "getting on it") the throttle response curve is DISGUSTINGLY more conservative than in normal mode....HOW STUPID IS THAT????
Trust me, I'm the "GM ELECTRONIC THROTTLE SCIENTIST" and have spent zillions of hours messing with the system... While I'm still at it....it will be a while before it's working.....it if happens.
Realize the disaster and troubles if "just once" a GM electronic throttle stuck open....For this reason there are dozens of redundant safety checks which have delayed the release of this very powerful tuning feature for LS2 family controllers.
Also realize that some of what you are feeling is also "torque management" if it's not turned off...
I'm on your side and I'm still at it... WE NEED THIS FEATURE...but, PLEASE be patient.
This has been a public service announcement from:
CHUCK COW
Peace
Chip
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Joined: May 2008
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i have a 99 with the a4 and i found the same problem. i thought it was my imagination at work.i have 3.15 rearend and car wont spin a tire. SAD have to powerbrake to get some spin. once moving this car does respond well so i guesss i will quit bitchin now. ed
Thread Starter
Drifting
Joined: Dec 2004
Posts: 1,706
Likes: 5
From: Toronto Ontario
Jornahow, thank you very much for your reply. I thought I saw your post at some point. I knew I wasn't the only one having this problem. I might send my PCM out over the winter and see if it can be taken care of.
Former Vendor
Joined: Nov 2005
Posts: 11,792
Likes: 255
From: Ossining New York
St. Jude Donor '07-'08-'09-'10-'12-'13-'14
I can fix it!
I've got an 02 A4 with 2.73's and I usually drive with my Active Handling on. It gives me slight bit of wheel spin which is usually enough to satisfy my needs. I turned the AH off recently after start up and noticed that the throttle response was not as good as when I turn the AH back on. I have try a few time afterward too to discover the same thing. I just wondered if this is a common thing with the C5?
Thanks
Thanks
I'll make it JUMP!
Chuck CoW
