ORIGINAL: formulagigi

GKB, no offense at al but why would you expect to beat a Maxima when your car weighs more and has less power. In addition, their engine is one of the best 6in the market, aside from BMW 6ers. The midrange torque is awesome, very efficient motor if a little unrefined compared to Bimmer for example.
You may have bought a "better" car tha your friend's as an overall packkage, certainly from an interior standpoint and looks... and it's even all relative... but it doesn't mean you bought a FASTER car.
I had a 2.8 myself and it seems everything short of my Jeep Wrangler is faster From a mod standpoint, I wouldn't waster my $ if I were you. As for engine swapping, you are better off selling the 2.8 and getting a 2.7T or 4.2.
As for your question, which is faster of the 2.7t and 4.2... although most say the 4.2 is.... I found that in spite of the HP advantage, the 4.2 is not always faster. If you get a 6spd 2.7t, you'd be right on par with a 4.2 Auto and might have a lsight edge in some situation from what I read and was told when I first bought mine.
I can tell you that my 2.7t TIPtronic with just a chip was faster than a stock 4.2, including the newer model. I raced a few, especially that one on the way to Atlanta and it could not keep up.
Now the 4.2 I heard is a rock from an engine standpoint, but the 2.7 block is a tough mama too. As for the stock turbos, I have seen 2.7T'swith well over 100k and no issues. it is all a matter of "taking care of it"... There is a thread in this A6 forum about what to do to keep your "baby" in shape... VERY basic things will keep your 2.7T running problem free:
- RELIGIOUS maintenance... Don't follow the service book directions with 10,000 miles intervals b/w services. I would suggest every 5,000 miles using only top premium synthetic oil. I personally use the Castrol synthec made in germany. Some use Mobil1, or penzoil.
- ALWAYS ALWAYS let your car warm up (175 +) before you gun it, before that I stay within 3,000rpm, which has more than enough power for every day driving.
- ALWAYS ALWAYS let your car cool down a bit before turning off the engine after spirited driving. Either drive the last few miles to your house at low RPM's or let the car cool down 30 seconds, maybr 45 is you really dogged it!
- Check the known weak parts at service times (search A6 forum)
- Upgrade the DV's to the N710 from the TT or spend $ on R1, Hyperboost... fancier DVs'.
- Upgrade to a SAMCO TBB or if you have $ the APR Bipipe.
- Do theTB&WP service early, 60k if modded, or 70k.
- Get a chip and and and... PIGGY pipes for reliability and performance. They decrease temp behind the turbos and wil probably give you an extra 20hp and 30 lbs TQ.
- if/when you do your auxiliary water pump under the intake, replace the gaskets with NEWSOUTH Powergaskets, some call them spacers. They will decrease operating temperature and also give you a little xtra OOMPH.
- Oh and brakes are not great in the A6, so i would upgrade to SS brake lines and better pads.

There's more, you'll find plenty of threads....
The 4.2 has one of the sexiest butt in the family sedan world and the 2.7 is highly tunable!

ORIGINAL: Kevin


I agree with Redshoe, out of the box the stock 4.2 will take the stock 2.7t. Once you start mods it all depends on the mods.

ORIGINAL: dmrdennie

The specs have the stock 2.7 a hair quicker because the 4.2 is heavier. If the 2.7 is modded, the 4.2 won't stand a chance. Gigi above kinda nailed it, plus I've had too many 2.7's beat my 4.2 since it was new. My own 2.7 beats my 4.2. Not by much but, it will beat it.