A4 with 3.90s?
Thread Starter
Burning Brakes
Joined: Sep 1999
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A4 with 3.90s?
Anyone out there running an A4 with 3.90s with stock internals or otherwise? If so what are your thoughts or opinions? Street manners? From what gear did you upgrade? ETor MPH increase at the track? And most importantly what RPM do you go through the traps at? Any input would be appreciated.
Thanks,
Mike :)
Thanks,
Mike :)
Le Mans Master
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From: Coral Springs Florida
Re: A4 with 3.90s? (Mikie C)
I've thought about it, but went the reliability of a factory sealed Getrag 3.73 unit..I really don't think you will notice the difference and you have a brand new part with less chance of breakage and service issues..Just my .02 :D
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From: Murphy TX
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Re: A4 with 3.90s? (Mikie C)
FWIW my Getrag 3.73 started leaking right on schedule at about 5k mi last fall. :rolleyes: After having run 3.73s for a while (running stock internals), I know I could easily stand a little lower gear. Would make me think twice about long highway cruises though and I'd need more tire to make it worthwhile.
RWhite recently opted for a 3.90 but runs a fairly large cam. Perhaps he'll chime in.
RWhite recently opted for a 3.90 but runs a fairly large cam. Perhaps he'll chime in.
Pro
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From: Rancho Cordova CA
Re: A4 with 3.90s? (Mikie C)
I have 390s with a auto, all I have done so far is to add a Trans go kit and cooler. The trans has held up to the blower and built engine for over 5k miles so far. Prior to the blower the 390s held up to 150 HP nitrous shot for over a year and a bottle every other week. I have been waiting for it (trans) to go for almost two years now. I put 335 on due to lack of traction. I’m sure the trans would let go if I put on some street ETs or slicks on but I have a vert with no roll bar so track time is out of the question. As to your questions about trap times and so forth I cannot answer. I will say that the 390s have worked out well for me on bottom end torque. I run a little over 9/1 compression, which should reduce my low-end torque, but I believe the 390s have helped in that area. My boost is set up over 10 lbs. I am about ready to install either a FLP (nice sale right now) or a Transmission Center Raptor unit. I had 315s. :cheers:
Melting Slicks
Joined: Feb 2002
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From: Winston Salem NC
Re: A4 with 3.90s? (Mikie C)
Mikie, hope you don't mind me adding in a question? I'm pretty certain that I'm going to a 3.90. The rpms at 70-75 mph are not all that bad. What converter? SS3600 SS3800?
Thread Starter
Burning Brakes
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Re: A4 with 3.90s? (jfpilla)
Vince
Yeah I see your point on the durability issue. As I have the 3.42s presently, I would like to go with a little more gear to make it worthwhile.
Topless
I also plan on a cam swap, but until then I don't want to nose over at the big end, as my car runs out of steam at 6200, hence my question about rpms through the traps.
Steve
Glad to hear that your 3.90s show some durability. Your car sounds like a monster :cool:
jfpilla
No problem. If it were me, I would definitely go with the 3800SS. It hits really hard and the shift recovery would be about 5000 rpm. This I know because a friend of mine has this TC with a stroker. I made a pass with it on a hot&humid day. It went 11.20 at 122. It sure felt good the entire length of the track. This would be perfect with your H/C combination and the 3.90s. Remember, the more gear you opt for the higher stall you will ned to get your best gain and drivability. Actually the Yank 4000SS may be a good choice. Talk it over with Mike @ Yank. Good Luck
Thanks all :)
Anyone else with some input, especially with the trap rpms
Mike :flag
[Modified by Mikie C, 8:16 PM 9/27/2003]
Yeah I see your point on the durability issue. As I have the 3.42s presently, I would like to go with a little more gear to make it worthwhile.
Topless
I also plan on a cam swap, but until then I don't want to nose over at the big end, as my car runs out of steam at 6200, hence my question about rpms through the traps.
Steve
Glad to hear that your 3.90s show some durability. Your car sounds like a monster :cool:
jfpilla
No problem. If it were me, I would definitely go with the 3800SS. It hits really hard and the shift recovery would be about 5000 rpm. This I know because a friend of mine has this TC with a stroker. I made a pass with it on a hot&humid day. It went 11.20 at 122. It sure felt good the entire length of the track. This would be perfect with your H/C combination and the 3.90s. Remember, the more gear you opt for the higher stall you will ned to get your best gain and drivability. Actually the Yank 4000SS may be a good choice. Talk it over with Mike @ Yank. Good Luck
Thanks all :)
Anyone else with some input, especially with the trap rpms
Mike :flag
[Modified by Mikie C, 8:16 PM 9/27/2003]
Melting Slicks
Joined: Feb 2002
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From: Winston Salem NC
Re: A4 with 3.90s? (Mikie C)
Thanks Mikie. That's just the info and encouragement I needed. 5000 rpms, wow, that's right where my power is. There's blown Buick pulling 7.30's. He turns up the boost when we race. I could get him.:crazy:
[Modified by jfpilla, 8:21 PM 9/27/2003]
[Modified by jfpilla, 8:21 PM 9/27/2003]
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From: Rockville Centre NY
Re: A4 with 3.90s? (vstella)
I've thought about it, but went the reliability of a factory sealed Getrag 3.73 unit..I really don't think you will notice the difference and you have a brand new part with less chance of breakage and service issues..Just my .02 :D
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Melting Slicks
Joined: Feb 2002
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From: Winston Salem NC
Re: A4 with 3.90s? (c5grandsport)
Also 3.73's are pretty loud when highway cruising when you've got headers/exhaust/etc, so 3.90's will only be worse.
Good point. Anybody have low gears with Z06 exhaust and headers? The 3.42 are not close to noisy in OD.
Anyone else with some input, especially with the trap rpms
In the 1/4: 3.90's would be just about 6300 rpms in 3rd and around 6000 with 3.73's.
Most of my racing is in the 1/8th. The lower the better.
Good point. Anybody have low gears with Z06 exhaust and headers? The 3.42 are not close to noisy in OD.
Anyone else with some input, especially with the trap rpms
In the 1/4: 3.90's would be just about 6300 rpms in 3rd and around 6000 with 3.73's.
Most of my racing is in the 1/8th. The lower the better.
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From: Suffolk, Long Island NY
Re: A4 with 3.90s? (jfpilla)
Mike, I hardly gained anything going from 3.15's to 3.73's. Also, if you like to drive on the parkway at 80 or above like me :D, the 3.90's will have the car screaming.
Thread Starter
Burning Brakes
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Re: A4 with 3.90s? (Face)
Mike, I hardly gained anything going from 3.15's to 3.73's. Also, if you like to drive on the parkway at 80 or above like me :D, the 3.90's will have the car screaming.
Yeah... I have heard that before about the small gain going to 3.73 with an A4. The high rpms at highway speeds would also be a big detrement for myself also. Thanks for the reply
RWhite
Thanks, 6400 would be too much for my stock internals.
Looks like I will have to look in another direction for some more OOOMPH, while still retaining stock internals.
Mike :flag :chevy
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From: Murphy TX
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Re: A4 with 3.90s? (Mikie C)
If you want the gear, maybe run a taller tire?
If you don't want to mess with the gears, a bigger converter. Heck, maybe a bigger converter anyway! :reddevil
Joseph, highway cruising noise is not bad with 3.73s either, LT+Corsa Indys here. For me noise is more of an issue at very low speeds with the loose converter and the lower gear helps some there. That said, it doesn't take much throttle increase at all at highway speeds to start getting loud and I'd expect 3.90 to be just a tad worse.
[Modified by ToplessTexan, 7:34 PM 9/28/2003]
If you don't want to mess with the gears, a bigger converter. Heck, maybe a bigger converter anyway! :reddevil
Joseph, highway cruising noise is not bad with 3.73s either, LT+Corsa Indys here. For me noise is more of an issue at very low speeds with the loose converter and the lower gear helps some there. That said, it doesn't take much throttle increase at all at highway speeds to start getting loud and I'd expect 3.90 to be just a tad worse.
[Modified by ToplessTexan, 7:34 PM 9/28/2003]
Melting Slicks
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From: Winston Salem NC
Re: A4 with 3.90s? (ToplessTexan)
I also find the exhaust louder when going up through the gears at slow speeds. Once I'm in OD it gets real quiet. Think it's valid to compare the exhaust sound at 85mph with the 3.42s and 73 with 3.90s?
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From: Lithia FL
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Re: A4 with 3.90s? (jfpilla)
J I have the the Z06 Ti with headers and 4.10. The noise in the car is very tolerable considering you are at about 2400-2500 rpm at 70 MPH. I switched from Corsa Indy to the Ti because of the noise (too many headaches).
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From: Murphy TX
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Re: A4 with 3.90s? (jfpilla)
I also find the exhaust louder when going up through the gears at slow speeds. Once I'm in OD it gets real quiet. Think it's valid to compare the exhaust sound at 85mph with the 3.42s and 73 with 3.90s?
REDGAR, surprised to hear that the Z06 exhaust is that much quieter than the Corsas at cruise. I would have expected them both to have begun getting a little loud at that point. Off topic, did you see my reply about the shocks?