Useful 3.2L M104 Specs and using Honda Connecting Rods - Page 8 - PeachParts Mercedes-Benz Forum

400Eric · #1 12-04-2010, 03:28 AM

You mean timing chain.

Maybe the cam phasing gizmos aren't working right.
Regards, Eric

JayRash · #2 12-04-2010, 03:46 AM

yeah i have the same feeling abt the advance thingies. I need to scan it but keeping up with all the expences of my cars been killing me. The AMG now now needs rotors all round a 600+ job in parts alone, atleast new rear shocks if not all 4 and new rubbers again.
I shut up i guessss atleast the W124s been doing ok as usuall basic service and thats abt it.

JayRash · #3 06-14-2012, 11:57 AM

guys have u ever known of this m104
m104.900: bore 81mm, stroke: 90.3 ; ;compression: 10:1; power rating: 174hp

it was made for the merc vito van

whatever · #4 06-21-2012, 04:40 AM

Quote:

Originally Posted by JayRash

guys have u ever known of this m104
m104.900: bore 81mm, stroke: 90.3 ; ;compression: 10:1; power rating: 174hp

it was made for the merc vito van

I'm sorry to disappoint you, but it's just a VW VR6 engine under MB badge.

Any way, did we get any another connecting rod option apart M103/M102 145 mm rods, M104 2.8 148 mm rods and M111/M102 2.5 149 mm rods?

Did anyone switch to crank guided rods?

JayRash · #5 06-21-2012, 05:20 AM

That's what I remember it was. But I didn't expect them to code name it m104

400Eric · #6 06-21-2012, 07:40 AM

I believe the 2.8 M104's rods are 149 mm too, not 148 mm.
Regards, Eric

whatever · #7 06-27-2012, 07:09 PM

I've got some info on OM603 92.4 mm crank in AMG 3.6 engine.

Pretty simple:

the OM603 3.5 L crank fits M104/M103 with minor machining:

the con-rods are simple 145 mm ones, but the piston is really short

The piston has a rough comp height of 27 mm (26.9 mm actual).
Here comes some shocking info on the rings:
1 mm - 1.2 mm - 2 mm
Which is really really really damn tight.

But actual "racing" pistons usually have same comp height with larger rings (oil ring intersects into the pin bore), like on these Nissan L28 pistons, which I have for the 3.1L stroker.

My 2 cents.

Modern Focus 1.6 Ti-VCT engine has a 25 mm compression height with some decent rings (I can take a pic, if interested). The only REAL problem is that con-rods are designed to have a small end to deal with side clearance. So finding off-shelf pistons is quiet a problem.
I heard some inserts can be made to control the gap between con-rod and pistons (when small end is dealing with side clearance)

400Eric · #8 06-28-2012, 02:29 AM

Great post with useful information! Thanks!

Are these parts in the photos from a C36 engine or are they from an older 3.6 AMG?
Regards, Eric

oldsinner111 · #9 06-28-2012, 05:04 AM

Pardon me: Does building a engine to 12:compression,do the same as turbo charging? Is it same power output?

400Eric · #10 06-28-2012, 09:28 AM

No. It would improve power by about 8% over your current 10 to 1 (assuming you get gas of sufficient octane) but a Turbo would add way more than 8% (assuming you get gas of sufficient octane).

You are thinking though, and that's good! Keep it up!

Now if only I could get you to start thinking about a lighter car!