• Hi Guest, welcome to TCG 2.0. Please refer to the FAQ in User Support before you do anything else. It will make the transition MUCH easier.

    IF YOU ARE SEEING AN "OOPS" ERROR PAGE, IT IS LIKELY BECAUSE YOUR BROWSER HAS NOT UPDATED YOUR CACHE. YOU CAN EITHER CLICK FORUMS AT THE TOP LEFT OR VISIT THECHICAGOGARAGE.COM AND BOOKMARK THAT. - Love, Mook

Dynoing a stock 2009 M3

Mook

El Presidente
Admin
Joined
May 23, 2007
Messages
162,574
Reaction score
724
Location
Elgin
Quick article from Edmunds I read this morning

This week's Car of the Week, our long-term 2009 BMW M3, starts things off with a hair-raising shred of sleepy Westminster, California's early-summer atmosphere.

That's where we subjected unsuspecting neighbors to repeared shrieks of the M3's 4.0-liter V8 as we caned it across its rev range range to the 8400-rpm redline at full throttle.

MD Automotive once again rented us time on their Dynojet chassis dyno for this exercise, which we undertook purely in the name of science. We swear.

BMW says the M3 generates 414 horsepower at 8300 rpm and 295 lb-ft of torque at 3900 rpm. Turns out they were right about the output.

Unlike in the M5, where the "power" button unleashes an additional 100 hp, pressing the M3's "power" button only sharpens the throttle response. The M3's owner's manual doesn't make any claims of additional power, but we checked it on the dyno anyway. Sure enough, we found the same power irrespective of the button's state.

In total, we performed four runs and they were all virtually identical. Run-to-run variation just isn't part of the M3's playbook. Normal aspiration has its advantages.



We apply weather correction for normally aspirated and supercharged cars. The SAE correction factor for this run is 1.05 since we tested the M3 on a relatively warm day.

This is an especially flat torque curve for a non-turbocharged engine. At 6700 rpm, the little V8 gets a second wind, too, and output swells upward once more before its very gentle taper as it approaches 8300 rpm..

Factoring in drivetrain loss, the 376 horsepower we measured at the M3's wheels is about what we'd expect from a 414-hp flywheel claim. Keep in mind that our result was achieved running California's crummy premium fuel, which is only 91 octane. Pretty impressive for a high specific-output engine like this one.

The lack of any significant sag in the power delivery between 3800 and 7800 rpm explains the engine's uncanny rev-forever character that you feel when you wind it out. It also demonstrates the significance of high revs when peak torque--we measured 274 lb-ft at the wheels in this case--is relatively modest in V8 terms.

Another observation is that although the M3 V8's maximum engine speed is indeed 8400 rpm, it really isn't the practical rev limit. Power clearly falls off so hard after 8300 rpm that the additional 100 rpm is useless. Come to think of it, early press releases listed this engine's redline at 8300 rpm. This ambiguity is likely a matter of engineering versus marketing.

Nevertheless, this V8 is one hell of an engine. What more is there to say?
 

Turk

Lt. Ron "Slider" Kerner
Joined
Jan 21, 2008
Messages
25,906
Reaction score
19
Greatest car ever made.
 

James

Well-known member
Joined
Jan 18, 2008
Messages
1,951
Reaction score
0
Torque is nothing if you can't put it to the ground because of a shitty rear diff.
 

Turk

Lt. Ron "Slider" Kerner
Joined
Jan 21, 2008
Messages
25,906
Reaction score
19
Torque is nothing if you can't put it to the ground because of a shitty rear diff.
Oh silly James. The M3 is not a drag car you silly goose, the rear diff is plenty strong, its the bolt holding it up there. You wouldn't understand, you don't have a car with over 200 hp. 5.5 + 5.5 = 12 right RAY!?!?!?! What a bunch of IDIOT!
 

Turk

Lt. Ron "Slider" Kerner
Joined
Jan 21, 2008
Messages
25,906
Reaction score
19
Well,

I thought TQ was meaningless. Cough....Cough...Couturkgh...Cough....
Tq is meaningless. Why do you think a LP 640 lambo is faster than a zr1 vette when it has 180 less torque and WEIGHS more?!?! Because it has 25 more hp.
 

James

Well-known member
Joined
Jan 18, 2008
Messages
1,951
Reaction score
0
The M3 is not a drag car you silly goose, the rear diff is plenty strong, its the bolt holding it up there.
Three excuses in one sentence, I'm calling Guiness, it's a world record.
How many extra rear diff bolts did you buy? Five or six? :picard:
 

Turk

Lt. Ron "Slider" Kerner
Joined
Jan 21, 2008
Messages
25,906
Reaction score
19
Three excuses in one sentence, I'm calling Guiness, it's a world record.
How many extra rear diff bolts did you buy? Five or six? :picard:
Hey ya bunch of idiot. A strong diff is an excuse, I only count two! I bought 2 extra bolts. What do you drive anyways?
 

James

Well-known member
Joined
Jan 18, 2008
Messages
1,951
Reaction score
0
Tq is meaningless. Why do you think a LP 640 lambo is faster than a zr1 vette when it has 180 less torque and WEIGHS more?!?! Because it has 25 more hp.
Spoken like a true ricer.
 

Turk

Lt. Ron "Slider" Kerner
Joined
Jan 21, 2008
Messages
25,906
Reaction score
19
Find me a car that has a hp/weight disadvantage and is faster James. THINK!!! Maybe if you didn't drive a car with less than 200hp and torque, you'd understand.
 

James

Well-known member
Joined
Jan 18, 2008
Messages
1,951
Reaction score
0
THINK!!! Maybe if you didn't drive a car with less than 200hp and torque, you'd understand.
That's it! I must get a 200+hp car and I will understand all things automotive.
Who fixes your broke ass cars? The dealer, not you?

K thanx bye. :rofl:
 

Turk

Lt. Ron "Slider" Kerner
Joined
Jan 21, 2008
Messages
25,906
Reaction score
19
That's it! I must get a 200+hp car and I will understand all things automotive.
Who fixes your broke ass cars? The dealer, not you?

K thanx bye. :rofl:
Yeah, that's right, I bought the bolts from the dealer so they could fix the car. You are a bunch of idiot.
 

Fish

From the mean streets....
Joined
Aug 3, 2007
Messages
36,117
Reaction score
21
Location
Chiraq
Find me a car that has a hp/weight disadvantage and is faster James. THINK!!! Maybe if you didn't drive a car with less than 200hp and torque, you'd understand.
Your camaro has less HP and is faster then your M. What do I win?
 

bluzohh6

The system works
Joined
Jul 2, 2007
Messages
10,570
Reaction score
0
Location
Elgin, IL
I have never seen an lp640 go 10.3

Not to mention Turk, weren't you present when a certain white lp got "smoked" by a blue vette?
 
G

Grabber

Guest
I was about to say, I have seen just mid 10's our of a ZR1 with just a tire and good driving.

The LP640 that weighs several hundred pounds more, with AWD doesn't need tires, and has never seen 10's. At least I haven't.

Also, how much TQ does the ZR1 have, compared to the 487 ft lbs in the LP640, yet has been proven to be faster with "25" less HP?
 

sickmint79

I Drink Your Milkshake
Joined
Mar 2, 2008
Messages
18,477
Reaction score
15
Location
grayslake
i don't care about this debate

but

the m3 engine is an extremely impressive package, and no mechanical engineer on this planet would claim otherwise
 

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Top Bottom