Restrictive Air Filter Assemblies

[Oversize]

Other observations about the factory housings are the snorkels are directing incoming air towards the internal hump or restriction plus the lid is concave directly above the air flap thereby decreasing headroom for incoming air to change direction.

If anything the lid should be convex in that area & the snorkels should be directing air towards the front of the housing. Obviously with the lack of space a rethink is in order. I’ll be having a shot at Dora when the time comes & making sure everything is totally reversible including a replacement hood.

 

[Patrick_R]

Mark,
As this all sounds very counterintuitive on the part of MB for air air intake. Is there any documents, testing or data showing why they would have designed it this way, like air swirl or ram effect due to what “appears” to be a restrictive area?

 

[Oversize]

I’m not aware of any raw data or evidence. I believe that up until the official AMG merger MB was focussed on reliability, comfort & safety. Performance & efficiency were not priorities & certainly nothing like the likes of Ferrari or Lamborghini. Yes there is definitely lots of room for improvement despite the advanced tech & quality incorporated for the era. For example, I don’t recall seeing any competitive racing Benz that retained the factory intake or exhaust.

 

[Oversize]

It is interesting that in the latter development of the W126, Benz were suddenly competing with the 300hp BMW V12 which was introduced in 1987. In response, they developed the 220kW M117 which included higher compression, knock sensors & the Tri Y exhaust manifolds. Interesting that the modifications did not extend to the intake area. Perhaps they achieved their objective within budget limitations & it was unnecessary to take things any further? Particularly when considering the substantially different M119 & W140/W129 were just around the corner.

 

[Oversize]

It is also worth observing that the early M119 featured a substantially different air filter housing despite still using K Jet. And the later M119 used a different intake manifold similar to the much earlier D Jet

 

[c107]

It is interesting that in the latter development of the W126, Benz were suddenly competing with the 300hp BMW V12 which was introduced in 1987. In response, they developed the 220kW M117 which included higher compression, knock sensors & the Tri Y exhaust manifolds. Interesting that the modifications did not extend to the intake area. Perhaps they achieved their objective within budget limitations & it was unnecessary to take things any further? Particularly when considering the substantially different M119 & W140/W129 were just around the corner.

I did some research into this at the time I wrote the 560 article on my website:

The M117.968 560 Engine

The 560 is the ultimate M117 engine. This family of engines was introduced in 1969 with the 3.5l M116 and was followed in 1972 with the 4.5 M117. The M1

www.classicjalopy.com

Basically the real response to BMW was the M120 V12. However, it was late so the 560 was seen as quick and cheap stopgap with the main focus on getting the V12 W140 ready that was supposed to come in 89. That's why they the minor interior refresh in 89 to tide things over to the W140 that was years late.

 

[Oversize]

Although the competition was good & potentially pushed Benz to develop their engines further, it also seems it encouraged Benz to respond with things like self closing doors. A neat gadget but really unnecessary & added complication, potential failure points, expense & extra weight. And of course extra weight is effective power loss....

 

[Oversize]

Slightly off topic some of the gadgets on the current BMWs are totally infuriating!!

 

[Oversize]

Mark,
As this all sounds very counterintuitive on the part of MB for air air intake. Is there any documents, testing or data showing why they would have designed it this way, like air swirl or ram effect due to what “appears” to be a restrictive area?

Carobu did testing & found various restrictions. But I’ve not seen any documents detailing why they were designed this way in the first place

 

[Patrick_R]

Carobu did testing & found various restrictions. But I’ve not seen any documents detailing why they were designed this way in the first place

One would think there would be method to the madness so to speak?