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Lowerd1
09-07-2006, 02:28 PM
2007 BMW 335i Dynamometer Run
By Jason Cammisa

http://www.automobilemag.com/features/news/0609_z+2007_BMW_335i+front_corner.jpg

The 2007 BMW 335i will be in showrooms next month, and is the first application of BMW’s new twin-turbocharged 3.0-liter inline-six. This is a big deal because BMW has had only two short affairs with turbocharged gasoline production cars--the 2002 Turbo in the mid-70s, and the E23 745i in the early 80s--and neither was sold in the U.S. As the saying goes, third time’s the charm.

BMW fit this new engine with two small-displacement turbochargers--instead of one larger unit--in an effort to reduce lag. And for the most part, it worked. Behind the wheel, you’re vaguely aware that this engine doesn’t have quite as crisp a throttle response as its normally-aspirated siblings do. But you don’t care--you’re too busy trying to hold on for dear life.

http://www.automobilemag.com/features/news/0609_z+2007_BMW_335i+hood_up.jpg

This is one hell of a motor, pulling smoothly and strongly from idle all the way to its 7000-rpm fuel cutoff. There’s no boost gauge, and since you barely hear the turbos spooling, it’s easy to forget they’re even there. Once you’ve adjusted to the slight lag in power delivery following big, sudden throttle openings, all you notice is the sound of that silky in-line six.

BMW says that this engine makes 300 horsepower and 300 lb-ft of torque. We were so impressed with its power that we couldn’t help wonder if that was a conservative rating. Wasting no time, I swiped the keys and drove to a local dyno shop to find out.

We used a DynoJet chassis dyno, which measures an engine’s power output at a vehicle’s rear wheels. Because of frictional driveline losses, this number is always lower--generally by fifteen to twenty percent--than the quoted power output from the manufacturer, which is measured at the engine itself.

Here’s what we found:
The non-turbocharged 330i, rated by BMW at 255 hp and 220 lb-ft of torque, puts about 200 hp and 180 lb-ft to the rear wheels. That’s roughly a twenty-percent loss. Since they have similar drivelines, you’d expect the 335i to put down 235 hp and 250 lb-ft.

http://www.automobilemag.com/features/news/0609_z+2007_BMW_335i+rear_corner_dyno.jpg

But it didn’t. It put down a whole lot more: 275 hp and 300 lb-ft. A few quick taps on our trusty calculator shows that this engine is likely putting out closer to 350 hp and 360 lb-ft of torque.

Technical editor Don Sherman’s ears perked up at all this number crunching. With all that power, he wondered, is the 335i faster than the outgoing 333-hp E46 M3? We waved goodbye to the shiny new coupe’s rear tires, and sent him to find out.

Don coaxed the 335i to 60 mph in 5.1 seconds--only 0.3 seconds slower than the M3. The 335i covered the quarter-mile in 13.6 seconds @ 104 mph--again, only 0.2 seconds and 1 mph behind the M3.

So in an all-out drag race, the 335i comes close, but can’t quite match the M3’s blistering acceleration. Those numbers, though, only tell half the story. Have a look at the top-gear acceleration figures. In sixth gear, the M3 needs 14.7 seconds to get from 30 to 70 mph – but the 335i does it in only 12.5.

That, my friends, is the beauty of this engine. At full bore, it’s as fast as an M3. But at moderate engine speeds, it’s even faster. What a great way to keep us all interested until the next M3 comes along.

Test - M3 - 335i
0-60 - 4.8 - 5.1
0-100 - 11.5 - 12.7
0-110 - 14.5 - 15.6
0-120 - N/A - 18.6
0-140 - N/A - 28.2
1/4 mile - 13.4@105 - 13.6@104
peak g - 0.7 - 0.68
30-70 (6th) - 14.7 - 12.5
30-70 (3rd) - N/A - 6.5

70-0 - 162 - 150
Peak g - 1.12 - 1.12

Weight - 3480 - 3560
%F/R - 50.6/49.4 - 51.1/48.9
Redline - 8000 - 7000
Power - 333 - 300
Torque - 202 - 300

Tires 255/40 ZR-18 255/35 WR-18


Thoughts?

SupaRice
09-07-2006, 03:35 PM
That's because they were using DynoJet, and got worthless power numbers as a result.

That car doesn't make that sort of power, and on an accurate dyno that 275 hp and 300 lb-ft would equal more like 245 hp and 270 lb-ft. (most likely less)

Moody
09-07-2006, 03:40 PM
That's pretty funny, because someone's new 335 just blew the f*** up all over the place over at the BMW forums. The car was stock, and new.

GT_Rat
09-07-2006, 04:40 PM
It will also cost as much as another 3 series to modify. Nice though.

SupaRice
09-07-2006, 05:06 PM
I really think its a winning combo. Since its German and it has true twins, I'm sure the turbos are horrendously small and suck, but there probably is still plenty of room for improvement with tuning and exhaust.

I'm sure there are lots of suspension and braking parts available for the E90, so I bet you could really turn one of those into a monster.

I'd really like to know what that thing would do with a medium frame single, because I bet it will be a demon with a good aftermarket kit.

Here's hoping. I can't wait to see results! :hyper:


I dunno, if it comes from Germany and doesn't say Porsche on it :down:

Exception would be M3, E46. Although, I still wouldn't own one though.

SupaRice
09-07-2006, 08:29 PM
The E90 is a proven chassis, drives the proper wheels a sporting car should, comes turbocharged from the factory, and has 50% more displacement than we do. What do you not like about it? :)

The fact that it has been designed by BMW. They simply must do everything completly different from every other car manf. Even if what everyone else does works, and has been tried and true for decades. I'm surprised they haven't come up with something other than round wheels! They are the most trying cars to work on ever, never will you have such a fury of bloody knuckles and swearing fits in your life. It's like turrets syndrome comes with the car.

Now if your were to gut it of all German electronics and mechnical lunacy, stuff something powerfull and reliable like a LS* Chevy motor in it... Then sure, I'd definately buy that. Because then you'd have a car that could handle well, unlike all things domestic, and run like the devil reliably.

Moody
09-12-2006, 06:38 AM
The E90 is a proven chassis, drives the proper wheels a sporting car should, comes turbocharged from the factory, and has 50% more displacement than we do. What do you not like about it? :)

That's funny you say this, Sethie, because between you and Chris V. saying that the Supra is an overweight pig, you just described it! I had to give you some ribbing! :lol:

PhoenixINX
09-12-2006, 10:20 PM
That's funny you say this, Sethie, because between you and Chris V. saying that the Supra is an overweight pig, you just described it! I had to give you some ribbing! :lol:

How did I get pulled into this???? :lol:

I'm curious to see how well boosted BMWs hold together. I have yet to build any trust with NA ones... :(

Jason
09-12-2006, 10:55 PM
All the performance of the previous M, for less money. I want. :drool:

PhoenixINX
09-13-2006, 09:46 AM
All the performance of the previous M, for less money. I want. :drool:

Ehhh...

3.2L NA revving out to 8k through ITBs > E90 Turbo :)

Good2GetBlown
09-13-2006, 06:00 PM
They seem to be pretty cool... But i would never buy another Bimmer (newer) to mod... The Ecu isnt the easiest to work with in the E46, i would hate to see what its going to take to tap into the E90... But I do think there will be some sweet ones out within the next few months.

Operator62
09-15-2006, 10:34 PM
Stock ECUs are simple to modify. Two steps really.
1. Remove stock ECU
2. Install Megasquirt

Just kidding. The newer bmws have really gotten too many electronics added into them. That's why I like to stick with the e30's and whatnot. Much simpler mechanically, and electrically. Sure, things are done differently than most others, but that doesn't mean it's necessarily a bad design. Some cases it is. Some it isn't. Every manufacturer has some designs that are just dumb, and some have some really great designs. It's just pretty much one of those, "to each his own", things.

Whatawookie
09-16-2006, 08:57 AM
Torque - 202 - 300

That's not correct. The M3 has 262lb-ft of torque.

The 335i sounds interesting, and the coupe doesn't look too bad. It's still too heavy, though. I would be much more interested if it were closer to the 3000lb range.