Useful 3.2L M104 Specs and using Honda Connecting Rods - Page 2 - PeachParts Mercedes-Benz Forum

RBYCC · #16 09-13-2010, 04:42 PM

Quote:

Originally Posted by MAG58

I surprisingly agree completely, Personally my favorite motor at the current is the 6.1L hemi and before that was the ol' 385 series Ford's. Cant beat those motors.

But the point I'm at is that there is physically not enough room for a decent rod/stroke ratio. The cost to get my diesel crank welded, re hardened, and turned down would make the cost skyrocket to the point where I might as well have a custom crank made. There has to be a minimum compression height to run any sort of forced induction (if you follow engine masters, you'll know some people have pushed the top ring and second ring together and run an oil control ring under it, just like F1, with a tiny compression height.

I know all about smokey. My old man was an SCCA lead tech when smokey tried to run his 7/8th size camaro through road racing tech, and more famously when they drained the gas after a race, he got in the car, fired it up, and drove off since he had extra fuel capacity stashed elsewhere.

I also know that smokey ran in displacement limited catagores (He turned those little DZ302's TIGHT back in the day) in which case, moving the rod/stroke ratio to a maximum for the displacement afforded will yeild the most power. But in a non displacement limited class, an increase in displacement on a street motor that will not live at 8500 rpm(SSSSSSS

) will produce a much more responsive midrange that extending the rod/stroke ratio simply will not be able to produce.

Also of note, by the time you do all the work to maximize rod/stroke ratio, you're still going to be doing it on mediocre hydraulic lifters which have crippled the high speed stability of the engine, ask JayRash. IMO money in getting custom parts machined vs off the shelf adaptations is much better spent in the top end of the motor. At least in the case of the M104.

So bear with me as I can be a bit slow....
With all the back and forth about crank design, trick/custom pistons, etc...are you concluding that in the case of the M103/M104 I6 Merc engines that the excessive cost per HP gained is not worth it ?

Difficulty is and has been that even if you can build a M103/M104 with mega HP that the chassis can't handle the torque available.

Not my words....more the comments from Aufrecht concerning chassis weakness in the 1987 "Hammer" which only pumped out a meager 355HP/388torque. They were breaking CV joints and axle half shafts.
Consider they were starting with a brand new unibody that hadn't experienced twenty years of metal fatigue.

Ed A.

nick.ged · #17 09-13-2010, 05:02 PM

amg removed the hydralic lifters from the 103 by cutting down the hight of the end where the hydralic bit fits, and fitting the manual adjusters from the cozzy.

i replicated this when changing the cam in my amg modded head, it aint no big deal, took about two days.

just be sure to take 2mm off the bottom as well, or the valves will bind and cant be adjusted.

MAG58 · #18 09-13-2010, 11:15 PM

But what about the M104 head Nick?

Ed, Are you talking about the drivetrain or the chassis? I'm not running hardly any factory mercedes parts by the time I'll be done. As far as the chassis goes, you do know that a big fat set of slicks on a road course will put more stress on the chassis than a 500hp engine could by quite a margin?

RBYCC · #19 09-13-2010, 11:30 PM

Quote:

Originally Posted by MAG58

But what about the M104 head Nick?

Ed, Are you talking about the drivetrain or the chassis? I'm not running hardly any factory mercedes parts by the time I'll be done. As far as the chassis goes, you do know that a big fat set of slicks on a road course will put more stress on the chassis than a 500hp engine could by quite a margin?

Unibody construction can create drivetrain problems under high torque due to flexing.
I would think you have to look at the chassis and drive train in a overall sense.

I never hear the mega HP builders speak of chassis reinforcement...from basic strut/shock tower bars, custom engine mounts and torque straps, to connecting the front and rear subframe assemblies...
Even a cage assembly will increase the stiffness of the unibody and eliminate flexing.

Agree with road course stress which is usually reduced by the mods I mentioned above...

My comment is directed to the majority of the 124's being built which seem to be happy going in a straight line with a great deal of smoke trailing behind it...

Making power is oft times simpler then controlling it...

Ed A.

Turbo E320 · #20 09-13-2010, 11:44 PM

A 20 year old civic body doesn't have the integrity to manage even 300hp but they are regularly built to well over 500. It's more for the fun and overtaking power of the cars.

I believe he is referring to both. The AMG w124 chassis had stiffening bars added in the rear, a stiffer subframe and stiffening in the engine bay along with the suspension mods. The AMG conversion does show how stiff the chassis is to begin with however. Very few mods were performed on the chassis.

Quote from 2007 August Mercedes Enthusiast:

Quote:

"The work to make a Hammer from a 200E was far from as comprehensive as Porsche's 1,100 changes to turn a 300E into a 500E. The making of a Hammer included stripping the car, making cuts in the engine bay for clearance, fabricating new bulkhead sections where necessary, reinforcing the engine bay and installing the big V8.
(Feyhl) The frame rails towards the rear of the engine bay had to be modified. We welded in stiffeners and made a new firewall that was also removable. The subframe, propshaft, and driveshafts were upgraded to take the much more potent engine, and we also added a US made Gleason-Torsen differential."

400Eric · #21 09-14-2010, 02:06 AM

Quote:

Originally Posted by RBYCC

My comment is directed to the majority of the 124's being built which seem to be happy going in a straight line with a great deal of smoke trailing behind it...

Making power is oft times simpler then controlling it...

Ed A.

That would be me then wouldn't it?
I drag race because I can do it all day long for $20 while a day at a road course is $150. The Hornet in my sig was originally a road racer complete with an 8 point roll cage, window straps, and a dead pedal but all I've ever done with it is drag race it and a little canyon carving with it.

You've at least got to give me credit for at least doing something with an MB at some kind of track. The vast majority of people don't do anything with their MBs except for putting loud sound systems in them and fancy wheels on them. Those are the ones I get frustrated with. I'm out there literally putting it on the line while they are out there just milking the image. http://www.youtube.com/watch?v=sOpeNXP0sMw http://www.youtube.com/watch?v=Sa5h4fq2Jkg

I've been running that ongoing thread here in the performance section for about 1 1/2 years now trying to get others to join me. You were the first gent to reply to that thread BTW saying in effect that you would go if I and the track weren't 3,000+ miles away.

Yes, it's true, making power is oft times simpler then controlling it, that's another reason we drag race instead of road race.

There's also less chance of wadding the car up on a dragstrip.

For the record, I also had a Torino that I did thoroughly enjoy paved oval track racing at El Cajon's 3/8 mile track until they closed it. (That was the track that Jimmy Johnson cut his teeth on. Too bad it's gone.)

Having said all that, I still would love to do road racing if it wasn't so expensive.

I also would love to field an MB in some "Lemons" races! Who's with me?
Regards, Eric

JayRash · #22 09-14-2010, 02:22 AM

I have to agree with Ed on this, My W124 with the stiffer springs, shocks and anti roll bars, along with the torque of the turbo setup, 17in wheels and my unforgiving driving developed cracks in:

1- both front lower control arms mounting points.
2- the rear sub-fame had at least 3 cracks in it.
3- the inner right mounting point for the rear sub-frame cracked and reached to the sheet metal under the rear seat.
4- Finally when my sis started to drive the car she managed to almost completely rip out the right strut mount.

I have completely rebuild my W124 front and rear and have reinforced the car in several places though its not subjected to as much stress as before. Just recently have succeeded in finding a strut tower brace which I will fit. BTW the car still never rattles, squeaks or feel saggy.
So yes those cars will show signs of fatigue if stressed, But then again my w124 was never driven with ease and has now 400k KM on it. so i would say subject it to stress and it will show signs of fatigue
But if i am to do it all over again, i would still drive it the same way i did. and fix what breaks, when it brakes.
But my advise is if your tough on your W124, do raise the car and look for cracks on mounting points, and fix any if found.

BTW, My W202 AMG has a tiny crack in the left front mounting of the lower control arm,
and the car only has 140K Km on it.

kynsi · #23 09-14-2010, 07:03 AM

About the 124 chassis which is similar to my 190.

Yes it needs some rebuilding, and some parts needs to be chainced time after time. But still it is fun and those parts are not even expensive. Biggest issue is that those four bolts whitc keeps the hole thing as one whith car body needs tightening, otherwise rear rubber contacts to the bottom of the car while rear axle is rotating backwards when accelerating 1 and 2 gear.

And upper rod (camper angle?) needs to be adjurtable type (raptec). That makes traction by keeping wheels straight.

Also wheel et number makers things worst, and how did Ed say: dont go too wide (or somethin like that). Heh...

MAG58 · #24 09-14-2010, 09:21 AM

Luckily for me my M104 isn't even going in a Mercedes!

I'm just tossing the stock ol' 3.2 in my W201 for cruising and daily fun.

The big motor is going in my Z... which is not even close to a stock chassis.

...In any way.

RBYCC · #25 09-14-2010, 09:33 AM

Quote:

Originally Posted by Turbo E320

A 20 year old civic body doesn't have the integrity to manage even 300hp but they are regularly built to well over 500. It's more for the fun and overtaking power of the cars.

I believe he is referring to both. The AMG w124 chassis had stiffening bars added in the rear, a stiffer subframe and stiffening in the engine bay along with the suspension mods. The AMG conversion does show how stiff the chassis is to begin with however. Very few mods were performed on the chassis.

Quote from 2007 August Mercedes Enthusiast:

That's the point I constantly try to make..
Rarely is the issue of chassis/suspension strengthening addressed...

Keep in mind that the "Hammer" conversion had a mere 388 torque at the flywheel...and yes AMG had breakage...

How does the 124 chassis handle claimed 900HP ?

RBYCC · #26 09-14-2010, 09:40 AM

Quote:

Originally Posted by 400Eric

That would be me then wouldn't it?

Eric...No I don't mean you !!!!

I'm referring to the You Tube smokers with thousands of foot pounds of torque...

If you're building a car to go fast in a straight line then you mod the chassis to accept the power and get it to the ground...

Tire smoke in a drag car means a loss of traction

I ran from SS/AA to SS/CA in a factory sponsored max performance hemi with the 727A torqueflite and the 9" dana rear...
Rear leafs clamped so tight they acted as one...ladder bars and unibody frame reinforcement...

No smoke on launch...just lifted one wheel off the ground...that's what torque does when you have bite...

RBYCC · #27 09-14-2010, 09:44 AM

Quote:

Originally Posted by JayRash

I have to agree with Ed on this, My W124 with the stiffer springs, shocks and anti roll bars, along with the torque of the turbo setup, 17in wheels and my unforgiving driving developed cracks in:

1- both front lower control arms mounting points.
2- the rear sub-fame had at least 3 cracks in it.
3- the inner right mounting point for the rear sub-frame cracked and reached to the sheet metal under the rear seat.
4- Finally when my sis started to drive the car she managed to almost completely rip out the right strut mount.

I have completely rebuild my W124 front and rear and have reinforced the car in several places though its not subjected to as much stress as before. Just recently have succeeded in finding a strut tower brace which I will fit. BTW the car still never rattles, squeaks or feel saggy.
So yes those cars will show signs of fatigue if stressed, But then again my w124 was never driven with ease and has now 400k KM on it. so i would say subject it to stress and it will show signs of fatigue
But if i am to do it all over again, i would still drive it the same way i did. and fix what breaks, when it brakes.
But my advise is if your tough on your W124, do raise the car and look for cracks on mounting points, and fix any if found.

BTW, My W202 AMG has a tiny crack in the left front mounting of the lower control arm,
and the car only has 140K Km on it.

Jay...

So what happens with a claimed 700-900HP in a 124 ?
Old design chassis have their limits.

I believe I just saw a post from "Roncallo" concerning a frame crack that just developed in his R107 with a great V12 transplant...