A8 power handling
 

I tried searching but maybe didn't find the right wording...

What kind of power can the A8 handle?

Sorry I am unable to help with your question, just wanted to say hello my friend...been a long time!

a lot. I think it is good to 1000 at least. Really is going to come down to how you launch. If you are at a track, and have turbos or a centri blower, it will be better than if you are at a drag strip, sticky DR tires, and have a screw style blower making big torque. The rear diff is going to break first, if that gives you any idea.

Specs are listed here. http://gmauthority.com/blog/gm/gm-transmissions/m5u/

Interesting specs. Says the maximum engine HP limit is 650 HP and the maximum torque limit is 635 ft-lbs. My little sticker in the cockpit says 650 ft-lbs of torque. Does the stock Z06 therefore already exceed the maximum torque reading or am I just misreading the info? And what is the difference between maximum engine torque (input to the trans) and maximum gearbox torque rating of 738 ft-lbs.? Curious as I know quite a few modified Z06 autos out there produce higher HP and torque numbers. --Bob

the zr1 also exceeds it.

Long story short, common sense is, that is the number that GM voids the warranty at.

The trans can and does hold 1000hp and similar torque numbers, no problem.

That's the manufacturer's rating, which may or may not mean much to a hot rodder, since it doesn't tell us what safety margin or excess capacity has been built in, either purposely or by accident.

After running about 550 horsepower through a V-6 Fiero transaxle for a while, I shipped it off to Getrag, because they were interested in checking it out. They tore it down, and said everything was fine. They did replace the blocker rings (synchros) since they had it apart anyway, as more of a courtesy than a need. Blocker rings or synchros are considered to be somewhat of a "wear" item, and I was mostly drag racing with this car, banging shifts as fast as I had the strength to do, which is really had on synchros.

Then it got even stranger. When I told a Ford powertrain engineer buddy about this, he said that this was evidence of Getrag having made a huge mistake, making the transaxle stronger than it needed to be for the initial application.

Yes, been a while. I hope all is well.

Thanks to all that helped with A8 info.

Spin it has been a while here as well. The C6 NA Corvette you helped me with is still running strong 9 years after I built it. To your question the trans appears to be good to at least 800 to 900 HP reliably and there are those here that are running 1000 plus HP. I can only speak for my car at 803 TQ and 743 HP. As stated above by Mike the rear spider gears seem to be the weak point when launching really hard with drag slicks followed by the stub shafts. Look up posts by jherbert and rflow306 here about a 4 spider gear conversion and new stub shafts from the driveshaft shop to resolve the problem. Another alternative is the wavetrac from RPM but you lose the e-differential when you do the wavetrac diff. and the cost goes up.

Spin, a very warm welcome back.

Roger that!