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Personally, I would not do a built trans until my stock 6L80 was broken. I've seen so many guys run problem-free with their properly tuned stock 6L80s with adequate cooling, then get a built aftermarket trans with the aftermarket trans shop's tune and they constantly had tranny issues after that. The built trannies don't seem to last as long as the stock ones. Won't name shop names. The fast A6 guys know who they are. I have seen some good reliability come from Circle D's built 6L80 and 6L90 transmissions however. Most of the really fast CTS-Vs run that box. But again, I hate seeing anybody fix something that's not broken yet.
I would agree with Pat here. Temperature and tuning are key. I did fry the 5/4/6 clutches in my stock one, but at that time I had no cooler and wasn't tuning it myself. Now that I do and have learned plenty about it, although the tune in it worked great, I don't believe it was what is best for longevity.
I read way to many horror stories about the built ones, and the prices asked are very high. I good rebuild with certain upgrades has been great so far. I will know more when I take it to the track, nearer to the end of the season. I want to enjoy my summer, not spend it with my car on the lift.
I am wondering the same. I have seen where alot of people say the stockA6 can only handle 550-600rwhp and similar tq. But have not seen any numbers for the RPM built A6 or any definative answer on if they have put together a 6l80 tranny for our cars yet. I have heard that if you have the tranny tuned it will be able to hold more power but not sure how that will affect how it holds power but hopefully CHUCK COW or some other Tranny Tuning people will jump in on this.
Here's the magic info..... Like Andy says, you can have upwards of 600/650 and not have it bust.
The things everyone needs to consider:
1) Who tuned it and what did they do. More TUNERS kill A6 cars than anything else out there. Even HP.
2) Put any trans in high gear prematurely or don't let it downshift with the onset of power....and it's BROKE.
3) Usage, Traction, and Tires..... What's going on? Transmissions don't brake if the tires don't stick. Nuff' said.
If you abuse the car, you'll break any trans regardless of how it's built. A lower power car with good traction
and sticky tires will kill a good trans easy.
4) Torque Converters and Rear ends..... Most of our bigger HP builds are for customers that we've advised from stock...
One of my favorite mods of all time was the A6 3.42 that pretty much happened here first. The 3.42 diff takes sooooo
much load off the trans, it can hold much better and the shaft is much less likely to break.
IN ANY CAR.... A tall diff ratio not only makes it a blast to drive, but gives the trans a HUGE amount of protection
and resistance to breaking given the gear reduction that takes the load off the engine and drivetrain and transmits it
to the tire and the pavement.... Very simple rule that too many people ignore or don't understand....Sad.
The A6 trans is amazing in what it can do given the proper tuning, and rear diff ration....
The A8 is even better.... All the same rules apply to it.
2) Put any trans in high gear prematurely or don't let it downshift with the onset of power....and it's BROKE.
Chuck can you elaborate on this ? Do you mean if my car is in drive, I have an A8 Z51. And I'm doing 60mph can I jist punch it and let the computer downshift? Is that bad for the A8? I can't see that being bad because the stock z06 guys do it I'm sure. My car will just have a base ecs kit at around 550-575rwhp. Also I'm sure you k ow this but in the A8 if I stab the throttle in sport or track it will automatically go into performance shift mode and downshift onto the lowest gear. From there you can punch it and take off. Is this better for the trans ? Sorry just trying to understand what you meant.
2) Put any trans in high gear prematurely or don't let it downshift with the onset of power....and it's BROKE.
Chuck can you elaborate on this ? Do you mean if my car is in drive, I have an A8 Z51. And I'm doing 60mph can I jist punch it and let the computer downshift? Is that bad for the A8? I can't see that being bad because the stock z06 guys do it I'm sure. My car will just have a base ecs kit at around 550-575rwhp. Also I'm sure you k ow this but in the A8 if I stab the throttle in sport or track it will automatically go into performance shift mode and downshift onto the lowest gear. From there you can punch it and take off. Is this better for the trans ? Sorry just trying to understand what you meant.
Chuck can you elaborate on this ? Do you mean if my car is in drive, I have an A8 Z51. And I'm doing 60mph can I jist punch it and let the computer downshift? Is that bad for the A8? I can't see that being bad because the stock z06 guys do it I'm sure. My car will just have a base ecs kit at around 550-575rwhp. Also I'm sure you k ow this but in the A8 if I stab the throttle in sport or track it will automatically go into performance shift mode and downshift onto the lowest gear. From there you can punch it and take off. Is this better for the trans ? Sorry just trying to understand what you meant.
The way that I tune my Automatics...... When you're in a particular gear, whatever it is.... If there's a lower
gear that will not over speed (rev limiter) the engine, I try to make the trans downshift to whichever gear is best
for the trans and engine together.
When you apply power (throttle) to a motor that's essentially cruising the engines start to DRONE, struggle,
and can even fail...Especially with a BLOWER.
Any time the trans is in a lower gear....It's able to handle more power.
Keeping the trans in a lower gear than stock makes them survive much longer and takes much of the strain off the
trans, clutch, converter, or torque tube making everything (including the engine) last longer.
We have minimal drive-train issues here, even with cars making much more power than stock largely due to the
way I handle My TRANSMISSION calibrations..... And the use of Higher than stock ratio differentials.
672whp here running 10.0 range in the 1320 on 1.5 60s. Circle D with a nice transcooler (derale bar and plate...with it's own shroud and fan (with thermostat) I plan to cut a better 60' with the new tires.
672whp here running 10.0 range in the 1320 on 1.5 60s. Circle D with a nice transcooler (derale bar and plate...with it's own shroud and fan (with thermostat) I plan to cut a better 60' with the new tires.
That's a good setup. Can't overdo the cooler and in some ways the looser converter helps dampen the
shockload on the trans from the motor.
Sounds like a great car.... The thermostat in the cooler is also a great idea.
My car makes about 1100 with my a6, I Built it myself and have made im sure hundreds of street pulls and its working great no issues at all I use shane hinds to tune the trans and even when bone stock the trans held 1000whp no problem. only reason I built it was because I knew it was only a matter of time before it broke.
Only thing this transmission is missing is a Trans brake and my car will go 8's pretty easy!
My car makes about 1100 with my a6, I Built it myself and have made im sure hundreds of street pulls and its working great no issues at all I use shane hinds to tune the trans and even when bone stock the trans held 1000whp no problem. only reason I built it was because I knew it was only a matter of time before it broke.
Only thing this transmission is missing is a Trans brake and my car will go 8's pretty easy!
What's your setup? Also curious what mph you're pulling at the track.
Don't think you can do a transbrake on a 6L80... never heard of one.
And the drivetrain wouldn't handle it anyway..
I have a TB in my 4l60, I tried it once at only 2500 rpms and it felt like someone hit the bottom of the car with a sledgehammer..... I immediately disconnected it.. Lol..
Not sure what my hp is but I have been a 6.06@118.3 in the 1/8 on my bone stock unit with a 3600 multi circle D converter. With the stock 2.56 rear gears it just a matter of winding out 3rd for the 1/4. Should be low 9.3x high 9.2x at 150 or so. It held fine. If I had to guess I'm around 860rwhp on spray.
Not sure what my hp is but I have been a 6.06@118.3 in the 1/8 on my bone stock unit with a 3600 multi circle D converter. With the stock 2.56 rear gears it just a matter of winding out 3rd for the 1/4. Should be low 9.3x high 9.2x at 150 or so. It held fine. If I had to guess I'm around 860rwhp on spray.
Nice passes!
Seems like the stock A6s hold up better then the "built" ones.. Lol
Not sure what my hp is but I have been a 6.06@118.3 in the 1/8 on my bone stock unit with a 3600 multi circle D converter. With the stock 2.56 rear gears it just a matter of winding out 3rd for the 1/4. Should be low 9.3x high 9.2x at 150 or so. It held fine. If I had to guess I'm around 860rwhp on spray.
This really makes me want a stall. I'm running 6.3-6.4 with the stock stall and stock 2.73 gears.
Very nice. What 60ft are you seeing. I have not been able to leave on much of my spray at all (10% over .8 sec) and this pass had a odd 1-2 shift. Once I get everything worked out I should be in the 5.8x with this mph. Still stock 2.56 gears here allows for 155mph in 3rd great for my set up through the 1/4.
05-17-2015, 11:15 AM
