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MAG58

Mercedes Benz M104 engine for the 240Z

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MAG58    13

I figured I'd finally make it official, the DOHC project got put on hold when I got a sizzling deal on all the pieces parts (minus rods and pistons) to make a MB M104.980 Stroker motor (Same as the C36AMG engine). So far I've been talking to the fine people at 190Rev.net on all the technicals for this engine and trying to piece together all the goodies to make it happy. At any rate, since my DD is my Z right now the motor cant get mocked up yet, but I measured and it should fit without cutting or big ol' fancy hood scoops.

 

As far as specs:

89mm bore and 92.4mm stroke (could go to 91 for full 3.6L but I want to stay with more wall thickness for a terbeaux :flamedevi)

Engine weight is 441lbs, I'll put it on a scale when it's built for sure to put up with BRAAP's definitive engine weights.

Head flow is unkown but now I do have a 90-92 and a 93-97 (production breaks) head so I can see which is a better flowing piece.

 

Anywho, here are some pics:

The head's all wrapped up so I'll just use my M104 to L series head comparo pics... It's the same head anyway.

 

 

First off, the block. M104.981ish 3.0L Engine Block

DSCN4073.jpg

Moar...

DSCN4074.jpg

Front of block:

DSCN4076.jpg

 

350SDL "Diesel" crank (Now not just limited to L series fun for strokers!)

DSCN4075.jpg

 

As a side note, the block has over 150k on it and the bores are still within a thou of origional specs, there are no ring marks at the top and you can still see the factory cross-hatch. The crank has something on the order of a bunch more and still plasti-gauged at .002 on all the mains, using USED main bearings(only to check clearances). I love german motors.

 

The Head!

Intake side:

DSCN0108.jpg

Exhaust Side:

DSCN0104.jpg

CC's

DSCN0109.jpg

 

Anyway, sorry if you don't like absurd amounts of pics in detail, I'm kinda anal about logging everything. More updates in a few weeks, block's going to get hot-tanked and I'm on the search for 280CE rods and forged pistons.

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Daeron    11
We all know that Mercedes copied the L28. :lmao:

 

*Audible*groan*

 

What does this engine look like in profile, from front-to-back? I am curious about its looks compared to the L-gata, sump-wise.... What is it going to take to hang it where it needs to hang in the engine bay, and for that matter, where in the engine bay will it sit compared to the L-gata?

 

Those are just the first couple of questions that haven't been answered yet. I love ALL I6 engines, and there is almost nothing I like seeing more than an I6 swap into a Z. A DOHC, 3.5-4L super-cool european race motor?!? YEAH!!!!

 

(i am a teensy bit excited about this. forgive me)

 

I suppose I could have simply said, "Subscribed!"

 

 

BTW I love this picture.. the blurry dude with hammer in hand in the background is an awesome touch

DSCN4073.jpg

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slownrusty    52

Can you give the exact model the block or engine came out? The C36 and all the straight six 3.2L all had head gaskets issues at no 5 and 6..this was a frustrating source to many MB owners, so a word of caution. These engines get VERY hot and if you are going to turbocharge it, be warned of the heat. Interesting swap and I am very intrigued, I am subscribing.

 

Yasin

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MAG58    13

The block is a MB 104.981 block, or the early "300-24" 3.0L block. It has the 89mm bore as opposed to the 89.9mm bore of the 2.8/3.2 motors and I do not plan on taking it to the 91mm that the C36 (actually a 2.8L) Block has to try and keep as much cylinder wall thickness in it as possible. I have already been talking to a bunch of individuals in Sweden that make big numbers with the M103/4 engines in turbocharged form and a custom Metal head gasket as well as a few cooling modifications will be on their way. This engine does however do fantastically well in turbocharged form, with the low power "base" M104 making 400hp and 500ft/lbs on 91 octane in an untouched motor/ecu (added injector in intake mani).

 

 

The hardest thing is going to be finding a tranny, because the transmission that fits is the 2.3-16 Getrag 260 (same as in the E30M3) which is a dogleg with no OD. I feel this would be bad for a bigger displacement turbo motor, so if any of you have any options, the clutch is figured out. I can probably adapt using the bell housing from the 722.6xx auto.

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MAG58    13

And for Daeron (sorry for the double post), The engine is shorter than the L series length wise (don't ask me how), has a 20mm taller deck height (same as the diesel) but is less than 20mm taller than the L series (also, have no Idea how this is with the head installed though) and about 30lbs lighter. The engine is front sump (much like a bimmer) but as short as it is, I should only have to lightly notch the front x-member to make it fit while the engine leans over and I will probably do and engine cradle similar to the SBF guys.

 

 

I wish I would have taken a picture of the engine from the side, it's really interesting how much the engine is engineered, all the ribbing is cast into the exterior of the block and there really is as much material removed as MB deemed possible.

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Daeron    11
And for Daeron (sorry for the double post), The engine is shorter than the L series length wise (don't ask me how), has a 20mm taller deck height (same as the diesel) but is less than 20mm taller than the L series (also, have no Idea how this is with the head installed though) and about 30lbs lighter. The engine is front sump (much like a bimmer) but as short as it is, I should only have to lightly notch the front x-member to make it fit while the engine leans over and I will probably do and engine cradle similar to the SBF guys.

 

 

I wish I would have taken a picture of the engine from the side, it's really interesting how much the engine is engineered, all the ribbing is cast into the exterior of the block and there really is as much material removed as MB deemed possible.

 

Hrmmmmmmm...

 

Hmmmmmmmmmmmmmm....

 

What about leaning her over on her side???

 

Getting that hot, hot exhaust down under where airflow can be directed around it then out the sides, leave you open for acres and acres of intake tract....

 

I am wondering what a Datsun with a slanted M-B engine might be "Eaton" for lunch............:burnout:

 

240 ZLK!!!!

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MAG58    13

It's already leaned over on it's side. Making the motor fit is not what I'm worried about, the engine is very good at producing large amounts of torque and I'm worried about finding a decent transmission that I can stuff behind it without Too much work that wont grenade.

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MAG58    13

Update:

 

First snag. Got the crank in and found a 280CE rod and piston for fit. This crank is massive :

DSCN0167.jpg

 

I stuffed the 280CE rod/piston in the bore, and rotated it through. Surprisingly nothing hit. It did however stick up a little bit...

DSCN0169.jpg

 

Apparently this is a 3/4'' stroke over the 280 motor. Fixing this may be an issue...that's .385 sticking proudly out of the top of the block

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neotech84    10
Update:

 

I stuffed the 280CE rod/piston in the bore, and rotated it through. Surprisingly nothing hit. It did however stick up a little bit...

DSCN0169.jpg

 

Apparently this is a 3/4'' stroke over the 280 motor. Fixing this may be an issue...that's .385 sticking proudly out of the top of the block

 

 

Naw it'll buff out!

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MAG58    13
What's the stroke on the 3.2 crank? Is it as heavily built as the diesel?

 

 

Yes, it's equally overbuilt, also equally forged, induction hardened at the journals and micro polished. I believe it's about an 84mm stroke. So about 8mm less.

 

Edit: With the 320 crank, the 280 rods, and 90mm K24 pistons, I will have a calculated CR of 8.8:1 (give or take .2), a 1.78 Rod/stroke ratio, and 3206cc's of displacement. I could spin the motor 8928rpms without hitting the 25m/s mean piston speed.

 

May just stash the crank away for a heavier car that needs some stroke to motivate it ;)

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Daeron    11
Yes, it's equally overbuilt, also equally forged, induction hardened at the journals and micro polished. I believe it's about an 84mm stroke. So about 8mm less.

 

Edit: With the 320 crank, the 280 rods, and 90mm K24 pistons, I will have a calculated CR of 8.8:1 (give or take .2), a 1.78 Rod/stroke ratio, and 3206cc's of displacement. I could spin the motor 8928rpms without hitting the 25m/s mean piston speed.

 

May just stash the crank away for a heavier car that needs some stroke to motivate it ;)

You say "280 rod.." is that 280Z or MB 280??

 

Going on a rough swag here.. the stroke difference is about 8 mm, if you mean to say that the short stroke, L28 rod, KA24 piston combo will do you OK for piston height, then maybe the stroker crank, an L24 rod (133mm) and a VG30 piston (pin height about 31.75mm) put you near the same height for the reciprocating assemblies.

 

According to this utility http://www.ozdat.com/ozdatonline/enginedesign/ there is a "JUN VG30DETT" piston that checks in at 89mm diameter.

 

 

 

Stro-Ker! Stro-Ker! Stro-Ker!

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