Yeah, I realized that when I scrolled back to the beginning of the topic.

For some reason, I thought that the different power curve (peak nm is 450 rpm earlier) in newer cars is related to that. Earlier motor even advances the cam 2 degrees more.

Wikipedia:
http://i789.photobucket.com/albums/y...M104_power.jpg

So making power earlier is purely coming from larger cylinder bore + HFM? I mean even smaller displacement 2.8 is doing that. An interesting fact is also that 170kw versions of old CIS motors are making 40nm 100 rpm earlier, where does that come from? It has to be related to cam, or the timing...?

Variable cam timing stretches out the power curve rather than increasing max power.

At some point I want to experiment with adding variable cam timing to the exhaust. A common trick is to use an exhaust cam on the intake side by drilling the cams face for oil. Ex on the intake si done to gain some valve lift. Adding variable to the exhaust just requires modifying the front cover for clearance and electromagnet. ( A later M104 multi coil ignition would be needed because early M104 had a distributor. )

There is also a 4 cylinder advance and C36 with different degree range as well. The C36 has less range and I'm pretty sure it is set up with more advance at idle,.

The variable length intake manifold on the HFM cars plays a decent role in moving the peak torque down in the RPM range. The LH M104 does not have the bottom end the HFM cars do in this setting. The C36 moved back up the rev range due to cam timing and intake duration

What years are you calling HFM / LH ? Also note that 97 got ME 2.0 / 2.1 + 722.6 5 speed electronic trans.

The LH Injected M104.990 in the 91-93 W140:
https://i.imgur.com/2qoIgaT.jpg

The HFM injected M104.9xx:
https://i.imgur.com/xTKq4nE.jpg

Yes, I was referring to that newer engines make peak torque earlier vs older ones.

Does anyone know if the cams are interchangeable in newer and older engines? Or cams from M120?

It would be perfect to have VCT in both intake and exhaust side much wider power cure and better fuel economy. I have done some research for my own stroker project. if anyone interested here is the pics of the 3,4L AMG pistons. I wonder if they are same as on 3.6?

http://i789.photobucket.com/albums/y...108_113718.jpg

http://i789.photobucket.com/albums/y...108_113615.jpg

http://i789.photobucket.com/albums/y...108_113547.jpg

http://i789.photobucket.com/albums/y...108_113547.jpg


Does the 3.0, 3.2 have same cams? What about the more powerful 170kw M104 3.0 or 3,2, do they have different cams too?


Found this forum post:

"All of the intakes are 9.5mm lift with 180 degrees duration @2mm and all of the exhaust cams are 9.5mm lift with 197 degrees duration @2mm"

Info found in catcams pages for stock stock M104 2.8 cams:

241°/261° - 200°/217° - 9.20mm/9.35mm - 0.30mm/0.95mm

The M120 uses an over / under timing chain so some of the cams run backwards. ( Intake ? ) This was discussed in the past year on this forum.

Also the pistons cannot be the same. The 3.4 is 91.5x84. The 3.6 is 91x92.4

Very interesting discussion indeed.

For some reason, I personally like the hardware on the earlier engine more. Maybe because they REV higher, and also they have more "meat" around cylinders making them in my eyes superior as a base to start with. I was not aware that the cam is variable on the .98 models as well so that's a very good find for me.

What I don't like about this engine is the rod ratio and the fuel injection part.
Rod ratio in M104.980 is 1,81. It's little better on 3,2 and 3,4 liter engine that has the same stoke 84mm and same length rods (145mm). Now the 3.6 L engine has rods from M104 2,8 that are 144mm right, making the rod ratio 1.56

Copy:
Typically, an engine with a higher rod ratio will produce a little more power from mid-range to peak RPM. Longer rods require the wrist pin to be located higher in the piston, or the engine has to have a taller deck height to accommodate longer rods. Longer rods also mean shorter and lighter pistons can be used, so the additional weight of the rods is more or less offset by the reduced weight of the pistons.

One of the disadvantages of longer rods and a higher rod ratio is that low RPM intake vacuum is reduced somewhat. Reduced air velocity into the engine hurts low-speed throttle response and torque, which is not good for everyday driving or street performance but works well on a high-revving race engine.

I wonder if there is anyone who has gone from CIS to fuel injected system and done 1:1 comparison how much is really hidden there and how much is really hidden in the intake manifold. If you look at the design on CIS intake manifold it has quite long runners that do not indicate it is a high revving engine but as always with OEM, they had to compromise many things for the sake of performance when they designed this engine.

Does the newer engine intake manifold bolts to M104.98 engines is the intake flange same and are the intake bolts on same location?

CIS has a different intake pattern than the electronic injection cars. I'm pretty sure all of the electronic injection cars had coil on plug.

LH Still had a distributor and was EFI.

Here is dyno from my M104 2.8 engine without the cam timing and intake resonance flap.

m104 question
 

good morning and please apologies for my question. I want to know if I can put a 1997 e320 m104 engine into my 1995 e320 if so what I need to replace or swap? thanks

1997 uses ME fuel injection where as the 1993-96 engines uses HFM fuel injection

Hi mates, does anyone have information about M104 .94x/99x camshafts? do they similar or different?