Whaaaaa???? I would strongly disagree with this - especially since I own a 2.7T and can consistently pull 26mpg on the highway at 75mph. I know of no 4.2 owner that could make such a claim.... with a straight face anyway.

 

Your right, I own a 4.2 and I could never say with a straight face that I only drove 75 mph on the highway . At a higher highway speeds my 05 4.2 does 24/25 mpg.

 

Four Ring Circus: True, I wish my 4.2 had a true manual. But it does have the tiptronic, which sucks in in 1st and 2nd, but works quite well after that point. And it does a good job of holding a gear if you're anticipating a need for power coming up.

Costner: I know it seems like a silly claim. A 4.2 engine using less gas than a 2.7. But take a browse through the reviews of these cars, and you'll usually find the same thing... the V8 using slightly less gas. But again, the difference is so little between the two it doesn't really matter.

 

Hmmm, Kevin - if you're traveling in excess of 75 mph and getting 24/25 mpg, I'd like to know your secret. The physics and the economy are at odds at speeds in excess of 55-60mph, so perhaps a reality check is in order here......

 

BTW - my 2000 2.7T is currently putting out close to 350 hp (thanks to a GIAC upgrade and some super-duper super secret stuff and I'm not telling and you can't make me!). While I can pretty much STOMP anything comparableout there at will, I freely admit that I don't get 25 mpg while pushing triple-digit speeds, but I can safely affirm that my baby turned in 29.7 mpg at between 60-65 mph (father-in-law at the wheel), drafting my Excursion (7.3 Powerstroke, 23.1 mpg, wife at the wheel), drafting my 36' Fleetwood motorhome (me at the wheel, getting considerably LESS mpg!). It's about drag and friction and engine rpm, etc.

 

BiTurbo,

Are you serious, the gas mileage numbers you are bringing to the table are drafting a motorhome. Well let me tell you about the gas mileage I got drafting the Space Shuttle [sm=gears.gif]

 

I have a 4.2 S6 and it's a manual 6 speed

I feel so lucky.... Anyone interested in buying it?

Well sorry, it's not for sale....

 

2005 4.2 - 335 hp, top gear ratio of .69, dragcoefficent of .29, frontal area 2.26

2000 2.7T 6M (as purportedly modified)- 350 hp, top gear ratio of .68, drag coefficient of .32, frontal area 2.18.

Sorry BT Pilot, your highway gas mileage is no better than my4.2. You are pushing5.71% more air and air is thename of the game on the highway. This 5.71% air handicap offsets the 1.45% RPM savings you have because ofgearing.If my math is correct I would have done approximately 30.9 MPG draftingyourmotorhome, not that such a scenario is "real world".

But don't feel bad, I am sure that with your4.29% hpadvantage you will "stomp" my stock car. Thoughwith your extra 4.29% in HP you are pushing an extra 5.71% in air, so I am guessing that while you may pull away from me at a stoplight, I am going to stick with you, or even pass you on the highway. After checking around, according to the MTM website with the governor removed my stock 05 4.2 tops out at 175 mph. The stock 2000 2.7T without governor tops out at 154 mph. Even with a "mid-level" MTM upgrade to 345 HP, comparable to your "top secret" 350 HP upgrade, your modified2.7T without governor tops out at 165 mph.

Confirming that air is the name of the game on the highway, when gearing is comparabale, I note that my air advantage is 5.71% and my top end advanatage is exactly the same at 5.71%. I suspect that on the top end your 4.29% HP and 1.45% gearing advanatge (total 5.74%) is negated because you achieve those numbers at lower RPMs and then tail off at higher RPMs. If the "mid-level" MTM upgrade to 345 HP is comparable to your "top secret" 350 HP upgrade,the peak HP in your 2.7T is generated at 6,200 RPMs, while my peak power comes on at 6,600 RPMs, or 6.06% higher. Myextra 6.06% in usable top end engine band allows me to get an extra 400 RPMs out of my car and negateyour extra 5.74% in power and gearing.

With ourpowertrains within 00.32% of each other for highway use, my car wins out on the highway because of the 5.71% air advanatge.With a 5.71% air advanatge my car wins on highway MPG and top endMPH. But don't worry, you and the WRX STi crowd will beat me off the line every time.

 

hmm, i have 2.8 and seriously, i missing power But i was chosing btw 2.8 and 2.7 and that twin turbo make me scared. One turbo cost 500-600 aprox. I know, nobody here dont drive with turbo normaly. When u stop the car, u need to wait for 2-5 min to get turbo cool. Hmm, nobody do that. That's make turbo les durability.

My next AUDI ill A8 with 4.2.

 

With regards to turbo cooling, their are devices that will keep the engine running for a period of time after you switch off depending on the temperature to ensure that your turbos are cooled, and not cooked when you switch off.

The make nice party tricks too.