190E 3.0-12v Turbo - Page 13 - PeachParts Mercedes-Benz Forum

RBYCC · #**181** 10-11-2010, 12:18 PM

Quote:

Originally Posted by Joreto

I forgot to mention that the body where the subframe is bolted begun to crack, guess it's due to the increased torque and partly to the stress from standing 1/4 mile starts . Has anyone had this problem , if so how have you gone about fixing it ? My guess is that the more powerful cars on here have run into this problem . I know that boosted BMWs can get/fit factory reinforcement plates from E36 M3 that solve this problem, my friend with the 328i turbo did just that. Are there such reinforcement plates for our cars, say from and 500 E ?

No different then the problem AMG had when they built the first W124 "Hammers"...
Keep in mind that AMG started with a brand new unibody that did not suffer from age fatigue.
From what I remember AMG fabricated custom reinforcing to strengthen the subframe mounting areas.

Why not ask Roman on how he reinforced his chassis to handle 700-900HP?

JayRash · #**182** 10-11-2010, 01:55 PM

My w 124 has stacked many miles of total unforgiving abuse. it developed cracks in the sub frame, righ subframe mount, seem weld under the rear seat cracked as well, all mounts of the of the lower control arms up front cracked as well. and finally the strut mount it self ripped from its place on the right side of the car. i have to say thou the car has now 400000km and our roads and the kind of abuse i put it thru is beyond what it was ever made to take, i have even had the front wind shld crack twice while hitting a corner very similar to going up lagunaseca's corkscrew.

back to how to fix it, simple scuff of the sealant tar that covers the the crack, might have to use a motorized metal brush so that u get thru the tar. then weld, i think same welding roman uses what ever u call that.

nick.ged · #**183** 10-11-2010, 02:51 PM

Quote:

Originally Posted by RBYCC

Why not ask Roman on how he reinforced his chassis to handle 700-900HP?

lol

JayRash · #**184** 10-11-2010, 03:36 PM

the rear subframe and mount can't take the torque, thats for sure.

Joreto · #**185** 10-11-2010, 03:39 PM

Ed, I was thinking of fabricating custom reinforcing plates for my car since we don't have the luxury of ones fabricated for our cars, like the BMW crowd has. Seems I'll address that when the time comes, taking off the subframe looks like big PITA. Frankly I don't see how the factory chassis can take 700-900 hp for a long period without major strengthening, unless the w124 is a lot stiffer than the w201. Keep in mind that I'm no where near that power, if my assumption is correct and I not way off , at 1 bar with the current turbo I'm in the 350 - 400 crank hp range (don't know about TQ, which actuality is the problem ). If every thing goes as planed I'll soon get it on a dyno.

Jay, my thoughts exactly.

RBYCC · #**186** 10-11-2010, 03:56 PM

Quote:

Originally Posted by Joreto

Ed, I was thinking of fabricating custom reinforcing plates for my car since we don't have the luxury of ones fabricated for our cars, like the BMW crowd has. Seems I'll address that when the time comes, taking off the subframe looks like big PITA. Frankly I don't see how the factory chassis can take 700-900 hp for a long period without major strengthening, unless the w124 is a lot stiffer than the w201. Keep in mind that I'm no where near that power, if my assumption is correct and I not way off , at 1 bar with the current turbo I'm in the 350 - 400 crank hp range (don't know about TQ, which actuality is the problem ). If every thing goes as planed I'll soon get it on a dyno.

Jay, my thoughts exactly.

Structurally the 124 and the 201 aren't that different...
Both designed to carry the maximum torque of the M103-12V....
That was why AMG had the problem in 1986 with the Hammer.

The 500E/E500 had subframes and mountings that were designed for a higher torque, but still not in "Hammer" territory !!!

I dyno'd with 7.5 lbs boost at 302 torque rear wheels...
This is more then double my base line 145 torque pre-TT install pull.
So easily double the published to the 375-390 torque range...

You should approximate these numbers..

Ed A.

BAD300 · #**187** 10-11-2010, 04:17 PM

er....right......just another thing for me to consider I guess

Thanks for this latest discussion guys......I think

JayRash · #**188** 10-11-2010, 04:23 PM

My subframe mounts suffered most from the hard shift of the tightened up auto from first to second. i had to tighten the shift pressure to protect the weak first gear bond from slipping. so all the force was taken up by the mounts and they gave up in the end.

add to that the million pot holes we have here and the speed bumps, and the chassis quickly shows the signs.

hell my stock C36 AMG already has a crack in the front lower control arm mount. and an odd crack on the right , tiny but odd, where floor joins the a front chaissis member, ill post pics soon.

i have to say the 36 is already over powering its chassis

BAD300 · #**189** 10-11-2010, 05:34 PM

Can't believe all this from these cars. I woulda thought these things were built much stronger than your average mass produced vehicle? When I first gazed on the bracing on the floor pans between inner sills & gearbox turret for example, they look like nothing I've ever seen.

Jap cars for instance have no bracing. Just the floor pan. Nothing else.

You guys have explained the torque is the culprut so I will be addressing this for sure. The fabricator who is doing 90% of the work for me is a panel beater by trade so I'm sure he can sort this out once car is running & regoed etc.

Again. Thanks a million for the info guys! One thing though.........the flex plate dilemma mentioned below. Wouldn't this be a problem mainly if you tramp it? Same for a stock diff. Tramp it & it grabs = BREAK!

Quote:

Originally Posted by Joreto

Perhaps this might be the solution to the u joint problem.

Pictures are from : http://www.paulspruell.com/gearbox_instructions.html

JayRash · #**190** 10-11-2010, 05:45 PM

Quote:

Originally Posted by BAD300

Can't believe all this from these cars. I woulda thought these things were built much stronger than your average mass produced vehicle? When I first gazed on the bracing on the floor pans between inner sills & gearbox turret for example, they look like nothing I've ever seen.

Jap cars for instance have no bracing. Just the floor pan. Nothing else.

You guys have explained the torque is the culprut so I will be addressing this for sure. The fabricator who is doing 90% of the work for me is a panel beater by trade so I'm sure he can sort this out once car is running & regoed etc.

Again. Thanks a million for the info guys!

they r the best built cars in the world but the metal is 20 yrs old now! its been hot and cold, wet and dry a million times. Its been twisting and relaxing just as much. Im glad its just this, french cars would have bio -degraded buy then, and as for jap cars, well they get way with it cause all the floor pan and every other part twists a bit. where as our cars have much stiffer compartments thus focusing the stress on the tiny mounts that were designed to reduce NVH transmition.

BAD300 · #**191** 10-11-2010, 06:25 PM

Quote:

Originally Posted by JayRash

they r the best built cars in the world but the metal is 20 yrs old now! its been hot and cold, wet and dry a million times. Its been twisting and relaxing just as much. Im glad its just this, french cars would have bio -degraded buy then, and as for jap cars, well they get way with it cause all the floor pan and every other part twists a bit. where as our cars have much stiffer compartments thus focusing the stress on the tiny mounts that were designed to reduce NVH transmition.

Jay. I was mentioning this property of flexing & the subsequent 'creak' heard in most cheaper cars as cars go over a driveway slant etc. I kinda figured the Mercs were stiffer therefore, the rigidity would result in far sideways/up down movement on the frame joins etc = less stress tolerance.

It just amazed me a little though.

Joreto · #**192** 10-12-2010, 08:08 AM

BAD300, also keep in mind that this bodies (w124/w201) where never intended/design to cope with two times + the power/torque of the stock engine, add to that the facts that Jay pointed out and the result is obvious. Fact is that with these cars if you increase the power of the engine you also have to strengthen the body to cope with the power.

Btw, one thing that hit me when reading forums (almost all forums on the net ) is that most people usually only share their success and seldom write about problems like the ones we are discussing. In my opinion the information must go hand in hand , thats why I bring such issues to the attention of the members of this forum .

RBYCC · #**193** 10-12-2010, 09:03 AM

Quote:

Originally Posted by Joreto

Btw, one thing that hit me when reading forums (almost all forums on the net ) is that most people usually only share their success and seldom write about problems like the ones we are discussing. In my opinion the information must go hand in hand , thats why I bring such issues to the attention of the members of this forum .

Joreto

Great comment and so very true....

I get into much discussion as the "devil's advocate" when many drool over "smoking" You Tube vids and claims of 700-1000 HP from a 124 I6...

Been saying for years that any vehicle is chassis limited unless serious mods are made to the chassis.

It's basic "Performance 101"...especially with a uni-body construction.

At the power output that both you and I and a few others are achieving, we are reaching chassis limits, more so with a manual transmission.

Best to make sure that the sheetmetal around the subframe mounting points are sound, and if not they should be reinforced.

Front and rear strut/shock tower bars are helpful and limit a bit of flexing.

For the claimed mega power the subframes need to be connected which is possible by an internal cage or channel extensions on the floor pan...

I'll say it once again...

"Power is useless if it can't be controlled"...

"Smoking" videos indicate a car that is not putting power to the ground...

Joreto · #**194** 10-12-2010, 11:30 AM

Quote:

Originally Posted by RBYCC

"Power is useless if it can't be controlled"...

I absolutely agree, also for me the form/area of the tq/hp curve (i.e. usable tq/hp) is more important than peak TQ/HP

.

RBYCC · #**195** 10-12-2010, 12:07 PM

Quote:

Originally Posted by Joreto

I absolutely agree, also for me the form/area of the tq/hp curve (i.e. usable tq/hp) is more important than peak TQ/HP

.

You've nailed it...

That's why I've always asked but never have seen the actual dyno charts/curves on the claimed mega power Merc I6's....

A numerical print out showing peaks means not a thing..it's the area under the curve that is all important...
No sense claiming you've pushed the horsepower peak to 9000 RPM when you can build a more reliable engine that will give you overall power from 2500 to 6000 RPM....
Not enough street to wind a 124 with a max 3.67:1 rear end ratio through the gears to reach a high RPM power peak !!!!