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+--- Thread: how many lateral g's can we get doing this? (/showthread.php?tid=1696)
how many lateral g's can we get doing this? - tilldeath - 09-04-2010
what is the most capable that we can make a mercedes diesel car?
how many g's are possible within the realm of stock suspension with minimal typical mods can the cars pull?
which models are best?
besides the newest cars of course!
and what mods would be required and by what manufacturer and at what cost?
thanks!
RE: how many lateral g's can we get doing this? - ForcedInduction - 09-04-2010
Find a skidpad and find out! I wouldn't do that sort of testing on any public street or parking lot, too many variables and too many risks.
Bigger sway bars make a big difference in body roll. The 15mm "special application" rear bar and 21mm wagon front bar are a great starting point.
RE: how many lateral g's can we get doing this? - garage - 09-04-2010
(09-04-2010, 05:10 AM)ForcedInduction Find a skidpad and find out! I wouldn't do that sort of testing on any public street or parking lot, too many variables and too many risks.
Bigger sway bars make a big difference in body roll. The 15mm "special application" rear bar and 21mm wagon front bar are a great starting point.
All the front sway bars on the wagons are bigger than the sedans? And they swap right over?
RE: how many lateral g's can we get doing this? - willbhere4u - 09-04-2010
I believe that is correct! The wagons all had bigger front sway bars!
RE: how many lateral g's can we get doing this? - ForcedInduction - 09-05-2010
Its only 1 or 2 mm, but every little bit makes a difference in torsion strength.
Royal PITA to change compared to the rear. You have to remove the brake booster, battery tray and all the coolant lines on the firewall.
RE: how many lateral g's can we get doing this? - garage - 09-05-2010
(09-05-2010, 02:21 AM)ForcedInduction Its only 1 or 2 mm, but every little bit makes a difference in torsion strength.
Royal PITA to change compared to the rear. You have to remove the brake booster, battery tray and all the coolant lines on the firewall.
Thats my whole philosophy behind tuning these cars EVERY LITTLE bit helps out.
I went and looked at how much of a pain it is, haha...ill get her done oneday, i think itd definetly be worth it.
Now what kinda vehicles did the larger rear bar come on?
RE: how many lateral g's can we get doing this? - ForcedInduction - 09-05-2010
(09-05-2010, 12:32 PM)garage Now what kinda vehicles did the larger rear bar come on?
"Special applications". Ambulances, funeral cars, heavy haul wagons, etc. Nothing in the USA.
I and a few others had to special order the 15mm rear bar from the Classic Center to get one. The last 5 new ones they had in the world went off the shelf in just a few days when the word got out!
Somebody made a 17mm rear bar from a W126L fit, but it doesn't "fit right". I haven't tried that so I don't know exactly what was wrong with it.
RE: how many lateral g's can we get doing this? - garage - 09-06-2010
(09-05-2010, 10:46 PM)ForcedInduction(09-05-2010, 12:32 PM)garage Now what kinda vehicles did the larger rear bar come on?
"Special applications". Ambulances, funeral cars, heavy haul wagons, etc. Nothing in the USA.
I and a few others had to special order the 15mm rear bar from the Classic Center to get one. The last 5 new ones they had in the world went off the shelf in just a few days when the word got out!
Somebody made a 17mm rear bar from a W126L fit, but it doesn't "fit right". I haven't tried that so I don't know exactly what was wrong with it.
Damn, thats exactly what i was afraid of!
Well i guess thatll be THE day when i see a w123 ambulance at the local PAP.
I would love to take my car on the skid pad and see how many g's it could pull, what a blast.
RE: how many lateral g's can we get doing this? - ForcedInduction - 09-06-2010
(09-06-2010, 10:44 AM)garage Well i guess thatll be THE day when i see a w123 ambulance at the local PAP.
Any MB nerd would get a semi from seeing one of those in the junkyard!
RE: how many lateral g's can we get doing this? - winmutt - 09-06-2010
(09-05-2010, 02:21 AM)ForcedInduction Its only 1 or 2 mm, but every little bit makes a difference in torsion strength.
Royal PITA to change compared to the rear. You have to remove the brake booster, battery tray and all the coolant lines on the firewall.
Speaking of semi's IIRC 1mm is like 17%.
Also upgrade rear sway bar links to the older metal version.
RE: how many lateral g's can we get doing this? - Kozuka - 09-07-2010
Messing with swaybar's will do more then just stop body roll. We're talking about over-steer under-steer. If you just want a stiffer suspension, changing the spring rates would be more effective. A larger front sway bar will produce more under-steer and a larger rear bar will produce more over-steer. When you start messing with the chassis dynamics they key will be testing, testing, and more testing. Too achieve the best cornering balance (which I consider to be a slight over-steer in a RWD but it's personal preference) will require more then just throwing on some sway bars and calling it good. Well, if you want to keep up with a W201.
Also I think that a electric fuel pump might be required, I've stalled out my wagon in high-g cornering with a 1/2 a tank of fuel it started sucking air.
RE: how many lateral g's can we get doing this? - winmutt - 09-07-2010
(09-07-2010, 03:23 PM)Kozuka Messing with swaybar's will do more then just stop body roll. We're talking about over-steer under-steer. If you just want a stiffer suspension, changing the spring rates would be more effective. A larger front sway bar will produce more under-steer and a larger rear bar will produce more over-steer. When you start messing with the chassis dynamics they key will be testing, testing, and more testing. Too achieve the best cornering balance (which I consider to be a slight over-steer in a RWD but it's personal preference) will require more then just throwing on some sway bars and calling it good. Well, if you want to keep up with a W201.
Also I think that a electric fuel pump might be required, I've stalled out my wagon in high-g cornering with a 1/2 a tank of fuel it started sucking air.
Not sure what you are getting at about stiffer suspension go with different springs. If you want lateral g's you want less roll. Less roll means more equal application of tire resistance. Increased spring rate will just reduce ability to compensate for the terrain.
RE: how many lateral g's can we get doing this? - Silberpfeil - 09-12-2010
Winmutt is exactly right. The best way to increase cornering ability is to increase the chassis stiffness as much as possible. On a road car too stiff spring rates will not allow the car to follow the terrain. A race car is different in that most tracks are "table smooth" at least compared to a lot of the roads we drive on.
An interesting thing I would love to experiment with would be magnetorheological dampers (shocks). But this is still for the most part emerging technology (at least for road cars) and I'm not even sure if custom applications are even available. (which are older Mercedes would most likely be). In short these dampers are able to alter their viscosity (and thereby stiffness) in milliseconds by altering the amount of electrical current going through the fluid inside the shock.
Here is some suggested reading if any of you are interested in pursuing your knowledge of chassis and suspension engineering further.
The prices listed are by Amazon. The Herb Adams book and the Carroll Smith book are both acknowledged as best as I can term "classics" for the field. Carroll Smith has written other books that are considered very good as well.
Chassis Engineering HP1055 by Herb Adams Paperback$14.93
Competition Car Suspension: A practical handbook by Allan Staniforth Hardcover$29.67
Engineer to Win (Motorbooks Workshop) by Carroll Smith Paperback$19.77
I forgot to say however that when a chassis isn't perfect (and which are??) increasing roll bar stiffness is probably the easiest way. Keep in mind though Lee Noble (probably without a doubt one of the greatest road car engineers alive) said that a properly designed chassis does NOT need anti-roll bars.
********
BTW-Could anyone please tell me how long it took them to change out the front anti-roll bar on a W123?. If I'm not mistaken "book" time was about 5.5 hours. Does that seem about right? Do you have a time for the rear as well?
RE: how many lateral g's can we get doing this? - Robert_UAH - 01-18-2011
What tires are you going to use? that will make more of a difference on the lateral g's in a skidpad then anything else. Race Tech had an excellent article on building your own swaybars and tuning the roll resistance of the car.
RE: how many lateral g's can we get doing this? - winmutt - 01-19-2011
(01-18-2011, 06:35 PM)Robert_UAH What tires are you going to use? that will make more of a difference on the lateral g's in a skidpad then anything else. Race Tech had an excellent article on building your own swaybars and tuning the roll resistance of the car.
URL for this article?
RE: how many lateral g's can we get doing this? - Robert_UAH - 01-19-2011
It is the November 2008 issue. I don't know if you can find it online.
RE: how many lateral g's can we get doing this? - Captain America - 01-20-2011
Cant sacrifice off road flex with bigger swaybars!
RE: how many lateral g's can we get doing this? - winmutt - 01-20-2011
PS You asked which car? I would say the 190 would probably be the best. Multilink rear and small. Barring that a 129 coupe would probably be second best.