3.90 or 4.10 with an A4? Need some constructive comments
Thread Starter
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
CI 6-7-8-9-10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
SFVetteman,
70264 B&M Supercooler Transmission Cooler, 24000 GVW, 11" x 6" x 1-1/2" is on it's way - ordered last week.
I have a 160degree thermo and the fans are programmed to switch on/off as follows : Low 185/175, High 195/185
My trans temps do not normally go above 196 F right now on a hot summer's day. If I push it really hard, 201 F is the highest I have seen. With the cooler it should be much lower.
Excellent info on the stall - thanks!!!
EG
70264 B&M Supercooler Transmission Cooler, 24000 GVW, 11" x 6" x 1-1/2" is on it's way - ordered last week.
I have a 160degree thermo and the fans are programmed to switch on/off as follows : Low 185/175, High 195/185
My trans temps do not normally go above 196 F right now on a hot summer's day. If I push it really hard, 201 F is the highest I have seen. With the cooler it should be much lower.
Excellent info on the stall - thanks!!!
EG
Drifting
Joined: May 2002
Posts: 1,607
Likes: 1
From: San Francisco CA
If you go to a high stall converter that cooler should be adequate for the street but on a road course, it most likely will not be adequate.
Using that cooler with my converter, my trans temps would go as high as 185 when driven hard through the twisties in 80-85 degree weather. Not bad but on a road course in similar weather it would hit 230 after 15 minutes. Not good so that's why I went bigger. Open track running combined with a high stall converter produces tremendous heat in the tranny.
If you don't already have one, get a Trans-go shift kit as it will improve your shifts and gives you greater control over the tranny.
Using that cooler with my converter, my trans temps would go as high as 185 when driven hard through the twisties in 80-85 degree weather. Not bad but on a road course in similar weather it would hit 230 after 15 minutes. Not good so that's why I went bigger. Open track running combined with a high stall converter produces tremendous heat in the tranny.
If you don't already have one, get a Trans-go shift kit as it will improve your shifts and gives you greater control over the tranny.
Thread Starter
Supporting Tuner
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
I already have a Transgo shift kit 
Melting Slicks
Joined: Dec 2002
Posts: 3,296
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From: Friendswood, Tx
Personal experience- I went from a 2.73 in my A-4 to a 3.42. After driving the car for about 4 months this way I can tell you that a 3.73 would have been too much gear for me. I do not drag race often, enjoy roll-ons and the occassional high speed blasts. The 3.42 has completely changed the car......I kick myself in the a$$ all the time for not doing the swap earlier.
I can also tell you from personal experience, with 3.42's your car will redline at ~161-164. My car with 550rwhp absolutely flew to 162, then ran out of gear.....I've done it 3 times. Pretty sad considering that I had my car up to 172 when I was only making 326rwhp with the 2.73.
Either way, your 2.73 has to go. You'll enjoy the car twice as much with a different carrier.
Jason
I can also tell you from personal experience, with 3.42's your car will redline at ~161-164. My car with 550rwhp absolutely flew to 162, then ran out of gear.....I've done it 3 times. Pretty sad considering that I had my car up to 172 when I was only making 326rwhp with the 2.73.
Either way, your 2.73 has to go. You'll enjoy the car twice as much with a different carrier.
Jason
Drifting
Joined: May 2002
Posts: 1,607
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From: San Francisco CA
Transmission must have been slipping because if you do the math 6000 RPM is 199 MPH Even if your converter is not locked and you have a high stall, high STR converter, 18% slippage seems excessive.
Thread Starter
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Originally Posted by PDRR
I did a 3.90 gear W/stock TC in my A4 and I love it. If I were do to it all over again, I would try to 4.10. Just my .02 Cents....
Did you run out of steam on the top end? What was it like on the highway at 80mph? Did the motor thrash? (meaning high rpm all the time)
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since no official racing...............get a nice 3000 stall, 3.73 gear, 305/315 tires and have a nice day
Instructor
Joined: Mar 2005
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From: Lusby MD
I did the 3.90, Transgo, and a Yank ss3600 sc 6 months ago. I don't race but love the spirited feeling of the gears. If I'd could afford to do it again, I'd put in the 4.10's with a higher sc. With the 3.90, I cruise at 2400 rpm at 70 mph.
Melting Slicks
Joined: Dec 2002
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From: Friendswood, Tx
Originally Posted by SFVetteman
Transmission must have been slipping because if you do the math 6000 RPM is 199 MPH Even if your converter is not locked and you have a high stall, high STR converter, 18% slippage seems excessive.
Funny you should say that......my car is at MTI as we speak having a Stage 4 tranny with a new converter installed. I made those 160mph runs with my stock tranny/converter which had about 10k miles of s/c use......maybe my tranny was on the way out?
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From: S.W. Ohio. . . . . . NRA Life Member
Originally Posted by Busa196
Personal experience- I went from a 2.73 in my A-4 to a 3.42. After driving the car for about 4 months this way I can tell you that a 3.73 would have been too much gear for me.
Jason
Jason
It's a personal choice when it comes to gearing and higher stall TC's.
one size does not fit all.
Team Owner
Joined: Jul 2004
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From: NJ
St. Jude Donor '05-'08
I am voting for the 3.73s so you can't beat me.... 
honestly it is a hard decision. The 3.42s might be a good choice, but they don't seem radical enough to me. The 4.10s with an auto would be way too much with your planned RWHP (assuming you add heads one day).
The 3.73s are probably a good choice. Still have some really good snap, but you don't have to feather the gas as much.
honestly it is a hard decision. The 3.42s might be a good choice, but they don't seem radical enough to me. The 4.10s with an auto would be way too much with your planned RWHP (assuming you add heads one day).
The 3.73s are probably a good choice. Still have some really good snap, but you don't have to feather the gas as much.
Le Mans Master
Joined: Jan 2001
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From: Lafayette Colorado
I am running 3.90 gears with a Vig 3800 stall converter. Totally great setuip. The gear ratio helps out a lot when the converter is not fully engaged. When the converter does engage, between it and the gears, hold onto your hat
Keith
Keith
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Originally Posted by MyFirstCorvette
Stupid questions:
What's does STR mean?
My totally bone stock 2000 A4 coupe's trans temperature averages about 215. Is that normal?
What's does STR mean?
My totally bone stock 2000 A4 coupe's trans temperature averages about 215. Is that normal?
See here for detailed info. http://www.converter.com/torqueratio.htm
Regarding temps:
I drive like I stole it, so one of the first things I did was a shift kit, 160degree thermo and reprogrammed my fans.
215F is probably normal??? - I only had my stock thermo for about 6 weeks after I bought my car in Sept 04, so I do not remember what stock temps were like
