tuner for diff ratio change
Thread Starter
Instructor
Joined: Aug 2022
Posts: 235
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From: SC
tuner for diff ratio change
I'm waiting for a diff with 3.73 gears to be finished. Any day now. I have a 3.15 in my car now, which is a 2002 Coupe with A4 trans. I know I have to set it up for this diff as far as shift points go but am unsure what tuner I need to get to do this with. The engine is stock and I'm not planning on doing any changes there so I don't need a dyno tune. What tuner is best for what I need? I keep hearing about HP tuners but which one? Or is there a better answer for such a simple project?
TIA
TIA
Le Mans Master
Joined: Oct 2008
Posts: 8,894
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From: Whitby Ont.
I'm waiting for a diff with 3.73 gears to be finished. Any day now. I have a 3.15 in my car now, which is a 2002 Coupe with A4 trans. I know I have to set it up for this diff as far as shift points go but am unsure what tuner I need to get to do this with. The engine is stock and I'm not planning on doing any changes there so I don't need a dyno tune. What tuner is best for what I need? I keep hearing about HP tuners but which one? Or is there a better answer for such a simple project?
TIA
TIA
.
Joined: Apr 2013
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From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
Drifting
Joined: Sep 2009
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From: Prescott, Arizona
Yes you absolutely need to have the PCM reprogrammed for a change from 3.15 to 3.73 rear drive ratio. If you don't have that done, shift points will be way off. When I changed from 3.15 to 3.73, the first indication was that the engine would hit rev limit at WOT and the transmission not upshift unless I lifted.
Sorry, my PCM was reprogrammed by A & A Corvette in Oxnard CA. https://www.aacorvette.com/
That said you could call them and ask about SC / East Coast.
Also try East Coast Supercharging and ask them- https://eastcoastsupercharging.com/
Sorry, my PCM was reprogrammed by A & A Corvette in Oxnard CA. https://www.aacorvette.com/
That said you could call them and ask about SC / East Coast.
Also try East Coast Supercharging and ask them- https://eastcoastsupercharging.com/
Le Mans Master
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Thread Starter
Instructor
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From: SC
Le Mans Master
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If you're really into tuning, then you can go ahead with the handheld. But since you're not doing any engine mods, and you just need a very simple tune, I also suggest going with someplace like ECS. However, it is your car. I'm sure the scan and tune guys can give you a good recommendation on a handheld. I had a SCT tuner for my Mustang many many years ago. With everything I've done with the Vette, dyno tune was the only (correct) way to go.