what makes the M3 engine...

[E30GoDz]

so powerful (relatively speaking) in stock form?? for its time it was crazy, a 2.3 4 banger with close to 200 hp?? what gives it the edge??

[Alex Mc]

many reasons..

high-flow cylinder head design, 4-throttle bodies pulling from a large plenum that is also fed by a large AFM. the compression ratio is relatively high, rod length is advantageous.. factory header is a full-length stainless piece.. aggressive setup, etc.

the S14 evolved from BMW Motorsport's race motors.. it's a track motor, turned street.

[M3 Ryan]

dual over head cams, 16 valves.
high revving capabilities, balanced beyond belief.

this motor was made to breathe and it does. It has a header instead of the typical exhause manifold. The intake is very advanced with tuned horns in the plenum to get the air right how it should. There are 4 throttle bodies which made for good solid air/fuel delievery which makes more power.

hope this helps!

[dallasbboy]

Not to mention a legacy of high performance automotive engineering skills that is simply something other car makers can not f.u.c.k. with.

The E30 M3 is a legend.


Brian

[M3Pilot]

Originally posted by dallasbboy
Not to mention a legacy of high performance automotive engineering skills that is simply something other car makers can not f.u.c.k. with.

The E30 M3 is a legend.


Brian

Hell yeah!!!!!!!!

I love the S14, it's not easiest car to drive in traffic, but this is not it's home. It needs something open were you can use the revs.
I guess it was pretty powerful engine of the time, as there are still many a car today that has F/I that doesn't put out the same amount of power as the S14.

The M power boys know how to build an engine, and when you think about is there is still a far amount of power to get out of the engine and still be realiable.
It's just the amount of $$$$$ it cost to get it.

[BimmerSteven]

Originally posted by M3 Ryan
balanced beyond belief.

What do you mean by this?

[vtecinside]

Originally posted by BimmerSteven
Balanced?

What do you mean by this?

It means all of the motors parts are made within tight tolerances (very small margin of error/variation. This is hard to do on mass produced cars because mass productions needs more room for error.

The advantage everything is as close to the exact levels and specs that the engineers designed the motor with, so it performs perfectly. This allows the motor to be a smooth as possible with minimal vibrations and quite often the ability to rev higher and faster....


the downside it takes a real detail (read:anal) oriented person to do this well.$$$$

noel

[Matt]

*tips hat*

good explanation. This is true of all bmws.

[BimmerSteven]

Originally posted by vtecinside
*text snipped*

This allows the motor to be a smooth as possible with minimal vibrations and quite often the ability to rev higher and faster....

noel

This is what I took the comment to mean, and I disagree with it. I find the M3 engine to be rather buzzy and the polar opposite of my inherently smooth I6 (325i) motor.

Compared to a friend's Honda S2000 motor (similar to the M3 in that they're both rev-happy 4 cylinders, DOHC, with high volumetric efficiency, close tolerances, and a sporting edge) the M3 is very edgy and anything but smooth. The same goes when comparing it to an Integra Type R motor (again, similar to the M3 in that it's a peaky, sporty 4 cylinder).

That said, all things are relative. Hopefully you understand where I'm coming from.

[dallasbboy]

Originally posted by BimmerSteven

This is what I took the comment to mean, and I disagree with it. I find the M3 engine to be rather buzzy and the polar opposite of my inherently smooth I6 (325i) motor.
Compared to a friend's Honda S2000 motor (similar to the M3 in that they're both rev-happy 4 cylinders, DOHC, with high volumetric efficiency, close tolerances, and a sporting edge) the M3 is very edgy and anything but smooth. The same goes when comparing it to an Integra Type R motor (again, similar to the M3 in that it's a peaky, sporty 4 cylinder).
That said, all things are relative. Hopefully you understand where I'm coming from.

You're forgetting that it took Honda about 12 years to get 200+ HP out a 4 cylinder engine in a mass production car.

In 1988 M3 was king like no other. Internally the E30 M3 engine has an amazingly complex network of engineering grace. You can't compare it to the S2000 or Type R. Go get an 88 Inetgra or Accord now thats fair, and it will be clear how ahead of its time it was.

Brian

[PrinceE30]

From what I've heard...(with respect to balancing)

The S14 is a highly balanced engine for a 4 cylinder. However, it still can't compare to the BMW inline 6. The company was build off of the great 4 cylinders, but once the engineers got the chance, it continued and grew with the power and smoothness of the BMW inline 6 (see E28 M5, E34 M5, E36 M50).

However, the inline 6 produces more power and torque down low (than the inline 4), which makes it an easier car to drive. EASIER. The "edginess" of the M3 comes from that Motorsport divisions strive to get maximum power out of the engine, without worring about how easy it is for Joe Smith to drive daily.

For an example, the intake of the E30 325 is meant to alow for a slow buildup of intake air. This makes the accelleration smoother and "easier" to drive, but reduces the amount of peak power that could be produced. The M3's intake, on the other hand, is huge and lets air in as the engine needs it. Thus the "edginess", as you say.

And as said before, high compression, big intake, big exhaust, etc make the 2.3L really give you lots of power up at high revs.

anyone?

-Prince

[Matt]

it took honda 12 years, variable valve timing AND lift, and a MUCH more advanced engine control system.

The M3 does have a higher displacement than either of those motors, though, which probably contributes to the vibration.

oh, and the s14 was derived from a racing motor, while the s2k motor (dunno the ##) was built for a street car, so i'm sure there are design differences because of that.

Prince: i think the high-RPM power comes from the high duration of the cams and the high flow through the throttles and the cylinder head.

[BimmerSteven]

dallasboy - I wasn't comparing the technological advancements of the different car manufacturers. I was merely using two other platforms that I am personally familiar with to show differences & similarities for the sake of comparison. Ease off.

Prince - I think you summed it up nicely. The M3 motor is balanced for a 4 cylinder given it's performance quotient.

Matt - displacement has nothing to do with how smooth an engine feels or performs. The 3.2l M3 motor in my friend's car is much smoother than my M20. This is due to numerous reasons, one of which is that the state of tune our motors are in vary greatly.

[Matt]

I guess that's true, i was really referring to the way displacement is arrived at... like a motor with a short stroke and long bore will probably be smoother than a motor with a long stroke and small bore (at the same displacement), because piston speeds will be lower, sometimes considerably.

I didnt want to just say that, though, because i dont know the bore and stroke of the motor in question.

the whole point of all of this was that a well-balanced motor will perform better than a normal one, and i think we are all in agreement on that.

[e30 Jeremy]

what does it take to convert the s14 into a non e30 m3 engine bay? will it interfere with the ECU settings?