M120/M104 Low compression pistons - Page 2 - PeachParts Mercedes-Benz Forum

CRS · #16 03-02-2014, 01:16 PM

Are you still out there mpower04?

Lincolnman · #17 03-06-2014, 06:36 PM

Everyone present, check in please.
I have made no progress personally - I am still fiddling with aftermarket injection options for the M120 and my motorcycle... never enough time.

GGR · #18 10-09-2015, 10:53 PM

Hi all,

I am resurrecting an old post. I am considering using an M120 for a project I have, mate it to a Richmond 5 speed manual transmission and use Megasquirt as engine management. I would like to keep the long block stock. My question is about camshafts. Are there any performance camshafts available for these engines? Google search did not yield any result. I'm asking here because if you're talking boring the block etc. you must certainly have looked into camshafts already.

Thanks!

whipplem104 · #19 10-10-2015, 09:03 AM

The simple answer is no. But it was not that long ago that this engine was still being produced for the Zonda. So AMG may have cams for that engine. I know the Cometic has headgaskets for the m120 in both bore sizes. Anyways it might be worth asking but I would assume a pretty hefty price tag.
Other options are simply to have the stock cams welded up and reground if you do not want to deal with shims etc. Or a smaller base circle will get you further without major head work. And then you can adjust with shims.

GGR · #20 10-10-2015, 09:25 AM

Thanks. Having camshafts welded/reground would be unchartered territory for me. I would prefer to keep to what has been tried before.

I may end up just playing a bit with camshaft timing and build a low restriction exhaust line. I'm more after modifying the engine character to get it well matched with a manual transmission, than big power. The M120 looks to be an over-square engine so must have the potential to be a happy revving motor.

Stock, max power and max torque are attained at rather low rpm. I guess retarding the camshafts, adding a bit of overlap and a low restriction exhaust line may make it more of a screamer, well adapted to the Richmond close ratio transmission.

R33V12TWINTURBO · #21 10-30-2015, 03:44 AM

Quote:

Originally Posted by mpower04

Hi Guys- interesting thread. I'm in the process of building a stroked M120 with titanium rods, and I'll also be going with custom pistons. My motor is '98 and had only 4500 miles on it before I stripped it down.

I will be boring the block for approx 92mm pistons, and I've done quite a bit of research on machining these blocks. The M120 block is cast from a special alloy called Alusil- it is essentially a hypereutectic alloy block, similar the piston material. There are a few machine shops in the US that have the know how and special tools to bore and hone these blocks and verify the results with a tool such as a Profilometer or similar instrument for contact surface texture measurement.

There are also a few porsche racing specialists (the 928 block uses the exact same alloy) that recommend to also then have the block Nikasil coated (Nikasil blocks are cast from simple alumiumim alloy and are Nikasil coated after machining) once the Alusil block is finish honed to provide an extra layer of protection. However there is a bit of debate on the validity of Nikasil coating an Alusil block, so beware.

I have complied quite a bit of technical articles on this topic if anyone is interested on reading ferther on the topic.

I haven't decided weather to turbocharge or not, so I haven't had the pistons or cams made yet. I'm also designing a bellhousing to mate the M120 to a Tremec TR-6060 6-speed if anyone is interested let me know.

Hi. I´m doing a m120 twin turbo with low boost, but I'm interesting learning more on how to raise the boost. So all the information you have will have interest for me.

thesheikh · #22 01-13-2021, 05:41 AM

Quote:

Originally Posted by mpower04

Sorry- ill also post the tech articles shortly

Cough cough. 3 posts and vanish!

Did you follow through on your build?

Lincolnman · #23 01-14-2021, 06:00 PM

Well, so long as the thread is back alive, I will weigh in.
Buildings are expensive and time consuming. As such, I have done almost nothing with my build. I would love some updates from someone actually getting anything done.
Back to your regularly scheduled programming.

Roncallo · #24 02-20-2021, 07:58 PM

Suggest if anyone is really serious, they contact Carobu Engineering

https://www.carobu.com/