I'm looking for information on how the AMG 3.4 M104.980 motor was built?


Data points I've found:


3.0L (CIS) bore x stroke: 88.5 mm × 80.2 mm

3.2L (HFM) bore x stroke: 89.9 mm × 84 mm

3.4L (CIS AMG) bore x stroke: 91.5 mm × 84 mm

3.6L (HFM AMG) bore x stroke: 91 mm × 92.4 mm


Would I be able to duplicate the 3.4 by using the 3.2L crank and the 3.6 pistons in an M104.980 block? Is there any issue with interference or connecting rod lengths I need to change out?


Does someone already know the answers to these questions?


Or what other ideas are out there for increasing the displacement on a M104.980 block?

didn't they use the diesel crank with journals shaved for stroke?

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

not journals counter balance's

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

Compression distance would be different between the 3.6 pistons and the 3.4 pistons. You can get custom pistons to get to the 91.5mm but with the steam cuts you run out of head gasket material pretty quick at 91.5mm and the HG seal will be a challenge.

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1993 190E 2.6 Sportline

I always thought the 3.4 was stroked not bored. 350sd/c36 crank, with short m102/m111 rods in the 980 block.

The 91mm bore of the 3.6 is already pushing it, I wouldn't want to go over that. Remember the head gasket trouble the Brabus 3.6 m103 used to have.

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87 w124 zender 3.6 - 3.0 kompressor in progress!
96 w124 e300 diesel - slowly being modded
98 w208 230 kompressor - m103 testbed SOLD.
96 s124 om606 superturbo diesel 508bhp

It was not. Well it was sort of bored and stroked. 88.5-->91.5 and 80.25 to 84 (the 3.0 OM603 crank, or the 3.2 M104 crank, they're the same).

I cant find the picture now, but there's one floating around the internet when they rebuild an E34 engine and the 91.5 was stamped on the pistons.

Also all the AMG engines used standard length 145mm rods. 3.0, 3.2, 3.4, 3.6 all used the same rods. Only the 2.8 used different rods, 148mm.

https://www.automobile-catalog.com/curve/1991/1568210/amg_300_e_3_4.html

91.5x84 = 3314CC
88.5x92.4 = 3410cc

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1993 190E 2.6 Sportline

Thanks for the link, I hadn't seen that before.

I tried a 3.6 crank in a .980 once but ran out of deck height with the stock pistons, even with shorter rods. Any other ways of getting a 3.4 without the 91.5mm bore?

__________________
87 w124 zender 3.6 - 3.0 kompressor in progress!
96 w124 e300 diesel - slowly being modded
98 w208 230 kompressor - m103 testbed SOLD.
96 s124 om606 superturbo diesel 508bhp

You will need custom pistons no matter what you do. The compression height is vastly different from a .98 to a .99 to things like the .941 3.6 or the .98(?) 3.4 build.

The 92.4mm crank will get you there with an 89 bore.
If you use an OM648 crank, you will have a 3.3 with an 89 bore.

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1993 190E 2.6 Sportline

Say I used the om648 crank with the 89.9mm bore and pistons, what would that take it to? I would assume it would need 143mm rods?

__________________
87 w124 zender 3.6 - 3.0 kompressor in progress!
96 w124 e300 diesel - slowly being modded
98 w208 230 kompressor - m103 testbed SOLD.
96 s124 om606 superturbo diesel 508bhp

Firstly AMG 3.4 used the crank from W140 M104.990 (300SE) 3,2
Second the 3.6 used 142mm rods
So they dident used the same rods.


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