BMW 335i dyno numbers - round two
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Last month, Automobile Mag generated some chassis dyno numbers with a turbocharged BMW 335i coupe that were a bit healthier than one would suspect, given the factory's rating of 300 HP at the crankshaft. In a follow-up, they're now stating that the 275 rear-wheel horsepower number that was reported was actually the lowest of four pulls; one even generated 283 ponies. And all of this was with 92 F ambient temps - the sort of air that usually kills the output of boosted engines. The publication then strapped a second sample to the same dyno, but this time in 78 F weather. Three runs yielded an average of 285 RWHP, with the other two varying from that by a maximum of three HP. Such consistency in the static air environment of a dyno is downright amazing and attests to the effectiveness of the Bimmer's intercooler and engine management system.
[Source: Automobile Mag]
Reader Comments (Page 1 of 3)
rwdmtparkingonly 9:55AM (9/22/2006)
100 hp/liter is what they and Honda do with NA engines, I would hope they could do a bit better than that with a direct injection turbo. The new Ecotech turbo does 130 hp/liter, if this engine had that much specific output it would have 390 hp.
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Anthem 9:57AM (9/22/2006)
Wow! It's been semi-long-held that the Bimmer Boyz make some of the best engines in the industry... these numbers certainly add credence to that opinion. Now all they have to do is figure out how to build comparably exciting and effective cars around them.
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Peter L. 10:02AM (9/22/2006)
With a drivetrain loss of 17% taken into effect, that engine would make right around 333hp (nice number, heh)
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Jason 10:02AM (9/22/2006)
I saw one of the new 335i up here in Boston the other day. It sounded darn good!
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Honda sucks 10:06AM (9/22/2006)
Hey #1, what does the Honda have? like 240 right?
300 > 240.
On top of that this has 300lb ft of torque at low revs.
Your precious Honda has like 120 lb ft at 9000. Enjoy not getting anywhere in a hurry.
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Honda sucks 10:07AM (9/22/2006)
Also if you want 100hp/L why not check out the M3 or M5.
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avixe 10:13AM (9/22/2006)
Or the VW 2.0T, or the Mazda 2.4 turbo, or the Acura 2.3 turbo, or the GM supercharged 2.0. 100 hp/L is no big deal with forced induction. BMW will no doubt crank up the boost over time, but I agree, it looks like the initial 300hp figure was arrived at by marketing, not engineering. (Exactly what people went after Porsche for with the Cayman, but apparently not a problem when it's BMW.)
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dreesemonkey 10:21AM (9/22/2006)
#1 - This is a TT engine, TTs are not for max power. Could they get much, much higher power from the engine? Absolutely, but that's not the goal for the car. They don't want to eat into the ///M sales, as most casual BMW owners would be satisfied with the straightline punch and not care about the other ///M performance upgrades and not opt for the M3/5/6.
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rwdmtparkingonly 10:26AM (9/22/2006)
#5: You're obviously new to cars, or just a brand worshiper, since you couldn't comprehend that I was comparing both BMW and Honda naturally aspirated (NA) engines to this new turbo. As I said in #1 “100 hp/liter is what they (BMW) and Honda do with NA engines.”
Both the Honda and BMW NA engines require high revs and suffer in torque.
My point is that I would expect a BMW turbo to actually have a higher specific output than their NA engines, not just compensate for low rpm power and torque.
By the way, Honda's new turbo makes 260 ft/lbs; if it was the size of this BMW engine it would make 325 ft/lbs.
Also, I drive a BMW and a Toyota, not any Hondas.
Develop your reading comprehension and stop being a 13 year old about brands.
dreesemonkey – You’re right, as avixe said 300 hp was a marketing decision to avoid threatening other engines, even though the M is going to a V8. It looks like the engineers didn’t want to be restricted to building a 100hp/liter turbo.
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Tony 10:29AM (9/22/2006)
Other than the styling (interior and exterior) that I find absolutely horrible...this is one of the few BMWs to actually excite me. For the first time I am interested in a BMW that doesn't have an M in the model name.
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Cosmo Kramer 10:33AM (9/22/2006)
HONDA SUCKS: You can't compare Honda to BMW. Honda isn't in the business of making production sports cars that produce tons of power. If they wanted to they could but that's not Honda's objective. I am ok with the fact you dislike honda but at least do an honest comparison. Only fools would compare Honda to BMW. I like Honda. They make a good product for the money. They make tons of reliable engines (largest engine manufacturer in the world). And yes, I agree with you that their engines could use more low end torque.
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Dr. Woo 10:48AM (9/22/2006)
Comparing HP/L between small engines and large engines is just folly. Typically, it's someone comparing a Honda N/A to something like the LS7. "If Honda built a 7.0L V8, it'd have 700 HP!"
It's all speculation, and it only makes you look foolish.
But I guess I'll bite...chip this (3.5TT) engine and you'll easily get your 100 HP/L. These engines are always perfectly capable of achieving that perceived-benchmark with a few computer tweaks.
Not a big deal.
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rwdmtparkingonly 11:00AM (9/22/2006)
Dr. Woo. Honda can't make a 7 liter V8 perform linearly with their 4 cylinder engines because they can't rev a .875 liter/cylinder engine like they rev a .5 liter/cylinder engine.
Comparing 3 liter 6s and 2 liter 4s is pretty legit because they both have .5 liters per cylinder, although it isn’t perfect since the bore/stroke ratios make be a bit different.
By the way Dr. Woo this engine is at 100 hp/liter because it's only 3 liters, everyone else knows that BMW is screwing with their alpha numeric naming on this car.
My point is that I'm not surprised this car is making more than 100 hp/liter with turbos, that's not a huge accomplishment, even if they're keeping low end torque high.
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Dr. Woo 11:18AM (9/22/2006)
Ugh. I knew I should have checked on the engine size. BMW and their confusing naming conventions.
But to make what one might consider a hypocritical point, comparing engines based solely on a few specific credentials (output, displacement, cylinders, induction) isn't very prudent. We have a similar setup in the RB26DETT, but at its least-powerful, that engine makes 332 HP from 2.6L. Not a very valid comparison simply because of the nature of each engine. One is for a luxury sport sedan, while the other is for a high-perf sports coupe.
Also, when's the last time you saw a "standard" BMW engine with class-leading HP numbers? Even the new G35 has an "unofficial" rating of 306 HP naturally aspirated.
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rwdmtparkingonly 11:38AM (9/22/2006)
BMW claims this 3 liter engine makes 300 HP. This article explains that chassis dyno tests are indicating that this engine makes somewhat more than 300 HP.
The tone of the article indicates that the writter is pretty amazed by this. I'm not, BMW may have tried to detune it for marketing purposes, but it doesn't impress me for a turbo 3 liter to make more than 300 HP and still satisfy BMWs low end torque and luxury objectives.
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G. Snyder 11:48AM (9/22/2006)
"Also, when's the last time you saw a "standard" BMW engine with class-leading HP numbers? Even the new G35 has an "unofficial" rating of 306 HP naturally aspirated."
Ummm...this is actually where the whole point of this article comes in. Sometimes raw HP numbers are not the most important thing. BMW tends to make very efficient engines AND drivetrains with minimal loss. This is not something new on the 335 - they have always strived for this. couple that with carefully chosen gearing and you will see why a car like a 325 or 330 performs on par with cars that, on paper, would seem to have left them far behind.
As an aside, I remeber Car and Driver running a group comparison of $35k-ish sport sedans. The G35 won, but they had to knock the BMW down to a 325 (e46) and even then it was close. The article went on to say that it seemed like it should have been a killing with the BMW giving up something in the neighborhood of 75hp (325i is rated at 184hp from BMW) and, while the G35 WAS much faster in acceleration the discrepency was not as much as you would have guessed.
My point is efficiency in translating power at the crank to power on the ground is a lot more important than generating massive numbers.
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jmfangio 11:58AM (9/22/2006)
Not sure if some of you guys understand how HP works.
horsepower at the wheels is always lower than at the crank. Therefore, 285 at the wheels is actually around 350-360, much higher than the 300 they are quoting..
In other words, BMW is under reporting the power created by the TT
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rwdmtparkingonly 12:12PM (9/22/2006)
#17, see #15. I'm not going to guess at BMW's drivetrain loss, but if this engine actually makes 360 HP then it's where it should be at for a BMW 3 liter turbo.
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Dr. Woo 12:16PM (9/22/2006)
"The tone of the article indicates that the writter is pretty amazed by this."
Yeah, I definitely agree with you on that. It's similar to the buzz generated when the SRT-4 was revealed to be quite a bit more powerful than its official rating, or the 2.0TFSI in the new VW/Audi vehicles. Perhaps this was marketing's intention all along.
"My point is efficiency in translating power at the crank to power on the ground is a lot more important than generating massive numbers."
Which is exactly what I was talking about. After re-reading my last comment right after posting, I realized I sounded like I was bashing BMW for not having the most powerful engine in its class. Definitely not the case.
"285 at the wheels is actually around 350-360, much higher than the 300 they are quoting.."
I wouldn't put it that high unless you were talking AWD.
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guyomatic 12:46PM (9/22/2006)
Hmmm.. anyone know dyno numbers for some of the car's competitor's? Like The Acura RL (300bhp) and G35 (298bhp)? I imaging that they would be less, but by how much?
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