Is a V6 better than an I6?

[The Choosey begger]

Originally Posted by GuidoK

Lol you've never been on the nordschleife....
Miata's are way to slow there. And an s2000 also isnt faster there than a Z4.
But you're right, we don't race on parkinglots here, we have 12 mile long racetracks

Sell your car if you're not happy with it.

Those are momentum cars they dont need a lot of power, you just proved you've never tracked or autocrossed. You're just going by shit you read on line.

[GuidoK]

Sell your car if you're not happy instead of bothering others.

Or go to a real racetrack instead of playing around on your parkinglot....

Even mercedes is going to use I6 engines again.

If you think 4 bangers are better then open a topic called "is an i4 better than an i6?"

[The Choosey begger]

Originally Posted by GuidoK

Sell your car if you're not happy instead of bothering others.

Or go to a real racetrack instead of playing around on your parkinglot....

Even mercedes is going to use I6 engines again.

If you think 4 bangers are better then open a topic called "is an i4 better than an i6?"

Mercedes makes luxury cars that handle like shit, i wouldn't use them as a pro ...

I hurt your feelings bc i think a v6 will help the 3 series, you need help

[GuidoK]

Originally Posted by anglo

I hurt your feelings bc i think a v6 will help the 3 series, you need help

yes its your word against all the engineers at bmw.....
I'm sure you're a better engineer.....not.

Sell your car and buy a miata. Be a man and keep your word!

[The Choosey begger]

Originally Posted by GuidoK

yes its your word against all the engineers at bmw.....
I'm sure you're a better engineer.....not.

Sell your car and buy a miata. Be a man and keep your word!

It's a daily driver, i co-drive an S2000.

[GuidoK]

If you're so convinced that an i6 is such a bad engine, then how the hell did you end up buying an m4?!?

What kind of stupid thought process was behind that?
Forgot to look under the hood?

[The Choosey begger]

Originally Posted by GuidoK

If you're so convinced that an i6 is such a bad engine, then how the hell did you end up buying an m4?!?

What kind of stupid thought process was behind that?
Forgot to look under the hood?

Any product has room for improvement, i also owned a V8 M3.
Our cars will really benefit from a V6, being stubborn and doing things a certain way because we always done this way is stupid!

Look at the Cayman, it's a better handling car than the 911 but on purpose Porsche sandbags the Cayman's perfomance!

It's not magic my friend, you need to understand physics...

[aaaaah]

Originally Posted by GuidoK

surely this honour goes to BMW ?!?
Having used I6's for so long when everybody went v6 and still managed to make cars that have superior balance on the track compared to most of the competition.

True, BMW have kept the I6 alive as an engine this whole time but MB has just opened up a way for every company that moved the V6 for packaging to move back to the I6.

It would be no different to another company making a rotary engine genuinely viable, yet Mazda is the one who has kept the design alive.

[aaaaah]

Also when in doubt about if an inline six is the best six. Remember.

[GuidoK]

Originally Posted by aaaaah

True, BMW have kept the I6 alive as an engine this whole time but MB has just opened up a way for every company that moved the V6 for packaging to move back to the I6.

Yes but like I said, MB probably wont be able to position this engine under the hood like bmw does. Look closely at the picture, one component there says it all.

It would be no different to another company making a rotary engine genuinely viable, yet Mazda is the one who has kept the design alive.

BMW has produced i6's by the tens of millions in the last decades in a multitude of chassis often outselling MB, I dont think they need MB to show it that the i6 is viable?

[eluded]

BMWs have in-line sixes and therefore it's a superior motor configuration.

End of story

[aaaaah]

Originally Posted by GuidoK

Yes but like I said, MB probably wont be able to position this engine under the hood like bmw does. Look closely at the picture, one component there says it all.

BMW has produced i6's by the tens of millions in the last decades in a multitude of chassis often outselling MB, I dont think they need MB to show it that the i6 is viable?

Looks like they have gotten it a decent way back to the firewall (E53 for reference).

Using this kind of tech could allow BMW to improve their weight distribution even more as it shrinks the overall length.

Being one of the few consumer vehicles with an I6 does not necessarily make it viable

[Red Bread]

Unless I'm looking at that wrong, I can't see more than two cylinders being behind the top of the shock towers. Pretty Audiesque placement.

[Red Bread]

Anyone venture a guess as to what the odd secondary intake on the exhaust side is for?

[img]http://performancedrive.com.au/wp-co...76-440x250.jpg[/img]

[hassmaschine]

Originally Posted by ScottSinger

back in the early 90's when Mercedes went from inline-6 to V-6, pretty sure they said the shorter V-6 would help in front crash impact. Who know's how much was sales or reality.

then I read the inline six at extreme high rpm the crank can wobble - so probably why you don't see dedicated race engine designs that are inline-6 - at least none I can think of.

Uh, what? The M88/S38? Many variations of the S50? (euro, not US) There have been tons of BMW inline 6's used in professional racing. Even the N52 was used successfully..

[aaaaah]

Originally Posted by Red Bread

Unless I'm looking at that wrong, I can't see more than two cylinders being behind the top of the shock towers. Pretty Audiesque placement.

I can't even see the top of the strut towers so you're doing better than me!

I just drew an imaginary line between the top of the wheel centres and there was probably about 2 cylinders past that line.

This is the only engine bay shot we have to go on right now so it's hard to guess from the angle.

[GuidoK]

Originally Posted by aaaaah

Looks like they have gotten it a decent way back to the firewall (E53 for reference).

It sits up front and sits up high. Both are equally bad. (remember that the strut towers are somewhere under those perforated pieces of plastic)
BMW uses a very neat but oldest trick in the book to solve that issue

Using this kind of tech could allow BMW to improve their weight distribution even more as it shrinks the overall length.

Shrinking it in lenght is always good, but mercedes has decided to shrink the lenght at the wrong side if you know what I mean

[Red Bread]

Yeah, it looks like the whole intake manifold is at the back, forcing that engine way forward. Fine for a taxi, though, so play on.

[floydarogers]

Originally Posted by GuidoK

...
Shrinking it in lenght is always good, but mercedes has decided to shrink the lenght at the wrong side if you know what I mean )

You *DO* know that BMW added length at the back of the engine with the B48/B58, don't you? Yet you haven't complained about that?

[GuidoK]

^you mean that the valvetrain distribution is located there?
or what?

[Red Bread]

Originally Posted by floydarogers

You *DO* know that BMW added length at the back of the engine with the B48/B58, don't you? Yet you haven't complained about that?

Nothing says fun like having to pull the motor to change the accessory belts or timing chain.

[GuidoK]

yeah bmw has been putting the distribution there for quite some time now on a number on engines, like the n47 and n57. And notably those engines have chain tensioner problem
I dont know what I would do, pull the engine or the gearbox. Maybe the engine on an automatic and the gearbox on a manual.
This is the acces from the gearbox side:


A good pic to see how much space it takes up. I think from a balance pov this isnt an issue, because the extra space is 2 chains thick (so about an inch I think), in which the chains, tensioner, chain wheels etc run. I think thats just as heavy as any 1inch crossection at any part of the engine. Also the oil pump sits now on that side with its distribution. And those parts need to sit somewhere. If its relative mass is on average as high as the rest of the engine it makes no difference except for servicing. The only advantage I can think of by placing it at the rear is that it may be less susceptible to harmonic vibrations prolonging its life (however one can wonder if thats the case, comparing the n57 valvetrain to my own m54 valvetrain that can virtually run troublefree for half a million miles and where a tensioner is swapped in 10 minutes if needed)

What I also was hinting about is that BMW doesnt use an ordinary I6 placement but under an angle, one of the oldest tricks in the book (I think chrystler thought of that back in the 50's). Also called slant (popularly at least), as in slant six.
I hadnt seen a pic of that m256 in a chassis but I immediately saw at the shape of the sump that MB wasnt going to do that, further comprimising an effective balanced placement of an i6 into a chassis and a missed oppertunity if designed a performance chassis.

Look at this pic and see how low and deep bmw's i6 sits in the chassis and then look again at that merc pic:

It sits way below the top of the strut towers, easily fitting a strut brace over it.
The merc's placement isnt even near that sort of placement.

And if you look even closer there are so many details that bmw thought of (or at least put into their design), for instance, look at these oilpans:
m54 oilpan:


B58 oilpan (couldnt get so many pics of this, but I found this one to show that placement of the oilpump isnt the issue if the carmaker does his homework):



Now look again at that m256 engines oilpan. Spot the difference!
BMW placed the deep side of the oilpan (where all the oil sits) behind the front axle. MB didnt.

All in all I think mercedes primarely designed this engine for fuel economy, good power delivery, smooth runnings but not a balanced placement otherwise they would have looked more closely at bmw's
The more you work on these cars and their engines and the more experienced you get, the more you discover the little details bmw thought of to perfect the balance and handling on these cars.
Thats why they build cars with i6 engines that outlandle a lot of the competition with v6 engines, while still profit from the superior points of an i6 like smooth primary and secondary balance, a distict cold side air intake which is good for both power, track stamina and longevity etc etc
Having a cold side to an engine also benefits other systems like the brake/brake booster system being able to run colder, which is better for braking stamina on tracks, so various systems interact on multiple ways. In that regard its especially interesting to take a very good look to a TVR with speed six engine or an old jag for that matter as they've incorperated a very very neat trick

BMW has mastered all these engineering requirements where a lot of the competition hasnt.