3.42's on an A4
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 876
Likes: 23
From: Prescott Valley, AZ
3.42's on an A4
What is needed to reprogram the PCM to change the shift points on an A4 when changing to 3.42s? An LS1 edit? Can the programming be done without it? Can a dealer do the reprogram?
Le Mans Master
Joined: Nov 2001
Posts: 7,033
Likes: 0
From: Cincinnati Ohio
Re: 3.42's on an A4 (mmorse)
Depending on what year it is, you might have luck with a Hypertech, but in an A4, the Diablo Predator is your best bet. LS1 edit can get you into trouble if you don't know what your doing. And many of us think we do but really don't. :lol:
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 876
Likes: 23
From: Prescott Valley, AZ
Re: 3.42's on an A4 (Buckmaster)
Cmon guys, you are not really telling me the best way to do the reprogram. There has to be a better way than buying a $400 predator just to do this one task. I do believe the car has 2.73's now.
Le Mans Master
Joined: Nov 2000
Posts: 7,294
Likes: 1
From: Coral Springs Florida
Re: 3.42's on an A4 (mmorse)
Cmon guys, you are not really telling me the best way to do the reprogram. There has to be a better way than buying a $400 predator just to do this one task. I do believe the car has 2.73's now.
I've been through 4-5 programs already and I wish I had the predator when I first started to mod.. :yesnod: Otherwise you can use Ed Wright at www.fastchip.com .
By the way ..If your not considering an after market torque converter at the same time you will be spending more money down the road for the same install :yesnod: Also now is the time for a Transgo Shift kit...A absolute MUST MOD for ANY A4!!! here's more info on the Transgo http://www.txchange.com/transgo.htm You can tahnk me later:lol:
If your interested in seeing ALL my mods on my 11 sec daily driver, I've documented them all with pics and videos on my home page...:D
[Modified by vstella, 6:48 PM 11/5/2002]
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 876
Likes: 23
From: Prescott Valley, AZ
Re: 3.42's on an A4 (vstella)
What about all these guys that have C5 automatics and have changed gears? You have to figure another $400+ for PCM reprograms on top of the gear install? As far as the other mods are concerned, I don't think my friend is interested in doing all that. He just asked me what would be involved in putting my stock Z06 3.42 dif into his coupe.
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Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: 3.42's on an A4 (mmorse)
No way around it..The program must be modified to accept the new ratio
I've been driving 10 months and 4k miles with 3.42's with a factory A4 pcm program... nary a problem; not even a hiccup. But mine was only an 8.6% change (had the factory 3.15) and my PCM was able to handle that monor variation.
I agree that reprog will provide better performance; but reprog is not a "must" in every case anyways.
.
[Modified by Mike Mercury, 7:53 PM 11/5/2002]
Melting Slicks
Joined: May 2001
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From: Novi MI
CI 2-3-4-5-6-7-8-9-10 Vet
CI-X Auto-X Champ (street tires)
Cruise-In IX AutoX Winner
Re: 3.42's on an A4 (mmorse)
I changed from 2.73's to 3.15's.
Before reprogramming the engine would hit the rev limiter in second gear and WOT.
The dealership reprogrammed my car for the 3.15's.
But, I doubt that they would reprogram for a set of 3.42's. :rolleyes:
The speedometer will also need to be adjusted.
You will probably need to go to an after market programmer.
Before reprogramming the engine would hit the rev limiter in second gear and WOT.
The dealership reprogrammed my car for the 3.15's.
But, I doubt that they would reprogram for a set of 3.42's. :rolleyes:
The speedometer will also need to be adjusted.
You will probably need to go to an after market programmer.
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: 3.42's on an A4 (01Pewter)
The speedometer will also need to be adjusted.
flat out - not the case with a C5.
.
[Modified by Mike Mercury, 7:48 PM 11/5/2002]
Race Director
Joined: Aug 1999
Posts: 15,466
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From: GARDENA Ca, State Of Konfusion
St. Jude Donor '05
Re: 3.42's on an A4 (Mike Mercury)
When I went to the 3.73's, Steve told me I was hitting the rev limiter. I thought it was a mis fire, the car drove great with the 3.42 programming around town. The drag strip was where the problem occured at WOT, the shift points needed to be adjusted along with the spedo.
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: 3.42's on an A4 (wallstAL)
wallstAL
you're running 3.73's with an A4? YOWZA! :eek:
I take it you have a higher stall TC as well. How to you handle traction issues at the strip?
you're running 3.73's with an A4? YOWZA! :eek:
I take it you have a higher stall TC as well. How to you handle traction issues at the strip?
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: 3.42's on an A4 (Mike Mercury)
Al; just noticed your:
DRAG STRIP ONLY
BFG Drag radials 315X35X17
Grand Sport Wheels 17X11
TCI Line Lock
remind me to never run against you at the track :lol:
DRAG STRIP ONLY
BFG Drag radials 315X35X17
Grand Sport Wheels 17X11
TCI Line Lock
remind me to never run against you at the track :lol:
Melting Slicks
Joined: May 2001
Posts: 2,596
Likes: 120
From: East Tennessee
Re: 3.42's on an A4 (mmorse)
You can get away without programming but its a good idea to do it. The speedometer is driven off the rear axle instead of the driveshaft like other cars so that will not need to be adjusted.
For a WOT upshift both MPH and RPM has to be met before the car will shift. The pic here shows stock shift mph/rpm for 2.73, 3.15 and scaled for a 3.42. Its easy to see going from a 2.73 to a 3.42 will hit the rev limiter before it shifts. My car with a 3.15 hits 46mph at 6100 rpm on the 1-2 shift but there is no way with a 3.42 it will hit 46mph to shift if the car has stock 2.73 programming.
Going from a 2.73 to a 3.15 or a 3.15 to a 3.42 will work with the stock rev limiter by looking at the tables but a 2.73 to 3.42 wont. There are other part throttle shift tables that will have to be scaled as well but most people probably wouldnt notice the difference..
Opps, I would find a local guy that does LS1edit tuning, I doubt they will give you a better deal if you just do one or two things but it doesnt hurt to ask. A dealer most likely wont do it. The predator is a good option and so is LS1 edit. LS1edit is not hard to use as people make out if you are just changing basic things..
[Modified by kp, 8:32 PM 11/5/2002]
For a WOT upshift both MPH and RPM has to be met before the car will shift. The pic here shows stock shift mph/rpm for 2.73, 3.15 and scaled for a 3.42. Its easy to see going from a 2.73 to a 3.42 will hit the rev limiter before it shifts. My car with a 3.15 hits 46mph at 6100 rpm on the 1-2 shift but there is no way with a 3.42 it will hit 46mph to shift if the car has stock 2.73 programming.
Going from a 2.73 to a 3.15 or a 3.15 to a 3.42 will work with the stock rev limiter by looking at the tables but a 2.73 to 3.42 wont. There are other part throttle shift tables that will have to be scaled as well but most people probably wouldnt notice the difference..
Opps, I would find a local guy that does LS1edit tuning, I doubt they will give you a better deal if you just do one or two things but it doesnt hurt to ask. A dealer most likely wont do it. The predator is a good option and so is LS1 edit. LS1edit is not hard to use as people make out if you are just changing basic things..
[Modified by kp, 8:32 PM 11/5/2002]
Instructor
Joined: Apr 2002
Posts: 181
Likes: 0
From: Brewster OH
Re: 3.42's on an A4 (kp)
I went from 2.73 to 3.42 in my Y2K. It was drivable but at WOT I would always hit the rev limiter. I bought the Predator for the sole purpose of correcting the shift problem. I installed the Predator program last Wednesday, the car acted the same as before (hit the rev limiter in all gears at WOT), I sent it back Friday, I talked to Johan @ Diablo today, he claims that they will have the problem corrected and returned to me by the end of the week. Hurry up and wait SOMEMORE. :sleep: :sleep: :sleep:
I had problems at WOT.
.....WOT upshifts should be OK but part throtle shifts will go a little higher because the car is made to upshift and downshift at different speeds with different gears....
I had problems at WOT.
