M50 vs M52 manifold

[m3f_OahuMPower_17503f01cd]

What if someone were to invent/design an intake manifold that had variable diameter intake runners.



I know it sounds funny, but think of it. If the intake runners had a smaller ID at low RMPS to maintain good airflow velocity/pressure, and they opened up to a larger ID as RMPS increased, we could have the best of both worlds......good top end power, and good low end torque.



CAD drawings please.... :taser:

[m3f_pbonsalb_ba5494e5cb]

What if someone were to invent/design an intake manifold that had variable diameter intake runners.



I know it sounds funny, but think of it. If the intake runners had a smaller ID at low RMPS to maintain good airflow velocity/pressure, and they opened up to a larger ID as RMPS increased, we could have the best of both worlds......good top end power, and good low end torque.



I thought something like that has been around for years -- two sets of runners per cylinder maybe.



Edit: dual stage not dual runner:



http://en.wikipedia.org/wiki/Variable_length_intake_manifold



Dual runner Nissan example also from a Wiki search:



"An improved version of the VQ30DE is known by the designation VQ30DE-K. The K designation stands for the Japanese word kaizen which translates to "improvement". The engine was used in the 2000–2001 Nissan Maxima and adds a true dual-runner intake manifold for better high-end performance compared to some earlier Japanese and Middle-East market versions of this engine. The VQ30DEK produces 226 PS (166 kW; 223 hp). The 1995–1999 US spec VQ30DE was equipped with only a single runner intake manifold."

[m3f_camdinans3_bfa1f49a41]

What if someone were to invent/design an intake manifold that had variable diameter intake runners.


I know it sounds funny, but think of it. If the intake runners had a smaller ID at low RMPS to maintain good airflow velocity/pressure, and they opened up to a larger ID as RMPS increased, we could have the best of both worlds......good top end power, and good low end torque.


interesting concept :hmm: but extremely impractical and super expensive. Pretty much makes the ITB conversion appear easy.


I thought something like that has been around for years -- two sets of runners per cylinder maybe.


Edit: dual stage not dual runner:


http://en.wikipedia.org/wiki/Variable_length_intake_manifold


Dual runner Nissan example also from a Wiki search:


"An improved version of the VQ30DE is known by the designation VQ30DE-K. The K designation stands for the Japanese word kaizen which translates to "improvement". The engine was used in the 2000–2001 Nissan Maxima and adds a true dual-runner intake manifold for better high-end performance compared to some earlier Japanese and Middle-East market versions of this engine. The VQ30DEK produces 226 PS (166 kW; 223 hp). The 1995–1999 US spec VQ30DE was equipped with only a single runner intake manifold."


no doubt they exist, its a good idea, but designing and producing a one off example....$$$$$ and no company is going to undertake that.

[m3f_pbonsalb_ba5494e5cb]

:hmm:...i find it hard to believe that schrick would spend lots $$$ on a piece that they sell for lots of $$$ when it's direct competitor, in the end, flows better...proof please



Flow more is not necessarily flows better depending on what result is desired. My point was that the Shrick may balance lower and upper rpm power or may simply flow all that a mildly modded S52 needs. I don't know the answer.



But yes, the M50 does outflow the Shrick and the data has been around for years:



http://www.bmw-m.net/techdata/m50vsm52.htm



Edit: Here is the Shrick (same guy tested all 3 but I can't find the version with them all side by side):



http://www.bmw-m.net/techdata/schrick.htm

[m3f_WRXEATR_c6f1d80be6]

FML.....and I thought I was on to something.......:lolhit:

[m3f_OahuMPower_17503f01cd]

why do you need another e46 M3 tranny spencer?

[m3f_WRXEATR_c6f1d80be6]

why do you need another e46 M3 tranny spencer?



My buddy who helped me do my gearing swap wants the same setup now....:shiftdriv



.....and Alex is out of euro 6's, i already asked him.

[m3f_Z3MCOUPE_0a03b38016]

I have not noticed and loss of low end torque after my M50 mod.

[m3f_WRXEATR_c6f1d80be6]

I have not noticed and loss of low end torque after my M50 mod.



me neither :clueless:

[m3f_camdinans3_bfa1f49a41]

me either :megashifty:

[m3f_cstern_8f12f914a2]

The ford probe/mazda mx6 from the mid 90's had a dual runner setup in the japanese version FSZE 4 cylinder. Four runners are always open and the additional 4 had butterfly valves mid way through the runners. The valves were vaccuum controlled iirc.

[m3f_I3MW_db2f80061a]

The stock software may not compensate for the larger injectors (that you don't need with so few mods). Skip the injectors, skip the software. However, software will include an rpm limit increase that will help you take advantage of the M50 manifold and may also help reduce the low end power loss of the larger runner manifold.


I think you're right, I don't think he needs fuel injectors but I don't see why you wouldn't get software (unless you are getting a bigger HFM and/or cams). The increased rev limit and spark advance will help. However, the tune cannot change that you switched manifolds, and can not restore any torque loss down low (proportionally to up high) you may or may not experience.


This goes back to the Schrick Manifold. Like I have said before, it is a good piece of engineering. Well thought out, for someone looking to bump up power with almost no downsides it is good (perhaps more so back in the day when it was cheaper) also, it is well matched for the duration and lift of their cams which makes for a very combo with a lot of torque across the range. You brought up a good point when you said that flow does not necessarily equal more power. So there must be a point where the maximization on the intake side and scavenging effect are out of reach for our engines. As many have pointed out this does not seem to be the case of the M50 manifold, especially with bigger NA power adders and a slight rev increase.

[m3f_fiveightan_7e37700daf]

The ford probe/mazda mx6 from the mid 90's had a dual runner setup in the japanese version FSZE 4 cylinder. Four runners are always open and the additional 4 had butterfly valves mid way through the runners. The valves were vaccuum controlled iirc.VTEC Hondas do this as well, it's not all that rare. Though there aren't manifolds like that available for the E36 M3.

[m3f_M3cosmos95_6e1ca51862]

me either :megashifty:



:agree:

[m3f_cstern_8f12f914a2]

VTEC Hondas do this as well, it's not all that rare. Though there aren't manifolds like that available for the E36 M3.



Was unaware that vtecs sis that as well. Just noticed someone had mentioned this idea earlier in the thread and offered an example. Would there even be a point to do it on an e36 m3?