MM Pulse Chamber Inlet Manifold

[Kedge]

I was just wondering if any of you have any experience of MM inlet manifold?

I've just had a quick read about Febi's car but he doesn't mention anything about the manifold.

Cheers
Dave

[cecotto]

I was just wondering if any of you have any experience of MM inlet manifold?

I've just had a quick read about Febi's car but he doesn't mention anything about the manifold.

Cheers
Dave

I wouldent know about it, but I think it's strange MM's the only one i've ever seen who makes them. My logic here is that if it was a fantastic upgrade, probberly more would be doing it.

 I would spend the money on another upgrade if it were me.

[bmwman91]

I wouldent know about it, but I think it's strange MM's the only one i've ever seen who makes them. My logic here is that if it was a fantastic upgrade, probberly more would be doing it.

 I would spend the money on another upgrade if it were me.

Not necessarily.  The M42 crowd is too small of a market for anyone to really care.  Basically, the E30 is just not the nest market for $$$ anymore.  The E36 is the new Civic, and people with E46/s / newer obviously have lots of cash to blow on CF shift knobs.  E30'ers are a lot of teenagers and a small group of older folks with real $$$.

I have heard OF this manifold, but do not know much about it.  Sounds neat though.  Resonance tuning IS HUGE, especially on a 4 cylinder.

[BrandC]

Sounds neat though.  Resonance tuning IS HUGE, especially on a 4 cylinder.

I'm learning about manifold and cylinder head flow dynamics in a high-performance tuning class right now. I spoke to my teacher about this manifold and he said MM has the right kind of knowledge.

I'm going to see if I can build my own. The power from the M42 is definitely going to come from head/manifold tuning, and possibly stand-alone.

I'll try to find some more info on resonance tuning.

[Kedge]

The more info the better guys, reading their explanation it does sound like it could make a difference.

I may have to look into getting one made as it'll be far too exspensive shipping one over to the UK.

[bmwman91]

The thing with the resonance tuning is that it is static.  It can shift power peaks around, but the resonance mods will only work best in a target range of engine speeds.  The BEST way would be to have some sort of variable depth pulse chambers that changed volume with engine speed.  BMW more or less does this on the new V10 M5 motor with the infinitely variable length intake track system.  Every bit of the system is important to this, which is very important to cylinder filling with the added resonance "ram" bonus.

For those who do not know exactly how it works, I have found the link below to be very informative.  While not a BMW, it is the same theory overall.  He talks a lot about a variable length intake system, and the E36 M42's intake manifold works on the same principle as the one he goes into detail on.
http://www.geocities.com/mikey9t6/car_uvwxyz_vris.htm

[cecotto]

BMW more or less does this on the new V10 M5 motor with the infinitely variable length intake track system.

I dont think the S85 (V10) has a variable intake tract system. It's got the Thottlebodies, and to those the two airboxes are attached directly. Inside the airboxes you will find five respective tracts of a static length.

It goes without saying that the tract length is tuned in length by the BMW engineers.  

But it does have variable cam timing on all four cams (2* dual VANOS).

[bmwman91]

I dont think the S85 (V10) has a variable intake tract system. It's got the Thottlebodies, and to those the two airboxes are attached directly. Inside the airboxes you will find five respective tracts of a static length.

It goes without saying that the tract length is tuned in length by the BMW engineers.  

But it does have variable cam timing on all four cams (2* dual VANOS).

Yes, I was wrong.  I am thinking of the motor in the newer 7 series.  I saw a diagram in Bimmer magazine a couple years ago showing this.  I was confusing my "large" BMNW motors!  The M5 uses Valvetronic though, right?  RealOEM does not seem to show it, but I thought it did.

[cecotto]

Yes, I was wrong.  I am thinking of the motor in the newer 7 series.  I saw a diagram in Bimmer magazine a couple years ago showing this.  I was confusing my "large" BMNW motors!  The M5 uses Valvetronic though, right?  RealOEM does not seem to show it, but I thought it did.

No Valvetronic on either the M5 or the new M3 V8. It's not good on high reving engines.  Actually BMW made the 320si without valvetronic to better facilitate the motorsport version of the engine. The valve actuation system on these engines are actually very much like the M42, with a bucket lifter.

But all three engines i just mentioned has VANOS, Which on motorsport engines often is removed.

As i remember pretty much all newer engines use valvetronic, 4-, 6-, 8-, 12-cylinder. But there might be a couple of exceptions...

[gearheadE30]

For examples of intake tract length, take a look at older F1 cars. Variable intake horns are now against the rules and Cosworth engines never used them, but most of the other cars had them. The horns were servo-operated and would extend and retract based on engine RPM.

[cecotto]

Not necessarily.  The M42 crowd is too small of a market for anyone to really care.  Basically, the E30 is just not the nest market for $$$ anymore.  The E36 is the new Civic, and people with E46/s / newer obviously have lots of cash to blow on CF shift knobs.  E30'ers are a lot of teenagers and a small group of older folks with real $$$.

I have heard OF this manifold, but do not know much about it.  Sounds neat though.  Resonance tuning IS HUGE, especially on a 4 cylinder.

With this design i would be concerned with unwanted turbulences, around the resonance chamber. I guess it could work at a certain RPM, but what about the overall picture.

I have never seen this design on any motorsport engines. Instead i've seen lots of effort being made to make the flowing path as smooth as possible (I'm not takling about mirrorfinishing the surfaces), But no sharp turns, every flange and port lined up perfectly, without any sutten change in size in the flowing path to introduce turbulences.

If you look at this image of my throttle bodies posted in another thread:


You will see what i mean, notise how smooth the transition between the lower manifold and the throttlebodies..

Well this is my view..

[D. Clay]

An easily understandable corollary is that a poorly designed intake will not deliver the same volume of air/fuel to each cylinder. All-Pro stock cars in the 80's had a 9:1 compression rule. Engine builders quickly adapted this principle to build engines that "ran" at greater than 9:1 compression but still read 9:1 when cranked over on the starter. The big buzz word was "cylinder pressure".

[christophbmw]

the new bimmers (dont know which models) do not even have throttle boddies, or camshafts. They have electronic/hydralic valves that open and close in relation to your throttle input. Ex: at idle the valves only open about 1mm or less, and at WOT the valves could open to lets say 10mm (completly tunable). Now, im not sure if its in the new '07 but it i think (if i read correctly) that it will be used on a select few of their '08 models. Just think about tunning and effieciency!

As for the MM pulse, my understanding was instead of the air/fuel mixture backdrafting up the manifold it would be trapped closer to the valve opening so when the valve opens again the vacuum would pull it into the cylinder. Correct me if im wrong but that is how i interpreted their little "story" on how it works.

[sheepdog]

The thing with the resonance tuning is that it is static.  It can shift power peaks around, but the resonance mods will only work best in a target range of engine speeds.  The BEST way would be to have some sort of variable depth pulse chambers that changed volume with engine speed.  BMW more or less does this on the new V10 M5 motor with the infinitely variable length intake track system.  Every bit of the system is important to this, which is very important to cylinder filling with the added resonance "ram" bonus.

For those who do not know exactly how it works, I have found the link below to be very informative.  While not a BMW, it is the same theory overall.  He talks a lot about a variable length intake system, and the E36 M42's intake manifold works on the same principle as the one he goes into detail on.
http://www.geocities.com/mikey9t6/car_uvwxyz_vris.htm

Exactly.
This is an old race trick it is not necessarily exclusive to them.

Jim did say the M42 lends itself perfectly to it though because of the manifold shape.