Lov2xlr8

then why was that CLK 430 the guy mentioned before limited to only 130 like most 230,320 and 430's?

ktm

The after market shops charge $1000 because they know that lil ricer boys will pay anything for not much in return.

pocholin

We are not lil ricer boys, but we will too

Improviz

LS1 Camaros, Firebirds, and Corvettes all have top speeds above 155 and are not limited. Ferraris, Porsches, Lamborghinis, Maserati, several others all sell cars in the US which top out well over 155. The 155 is an agreement between the German manufacturers (except Porsche), I've read this in several Auto magazines (both American and international).

JBrady

Well, at least most German cars get the 155mph limiter. Japanese cars are usually set at 149mph. I spoke with the folks at "The Racers Group" that sell and tune the Unichip and was told the limiter was easily defeated with this product. It is very difficult to change the parameters within the stock ECU but by intercepting the signal, either before or after the ECU, you can modify almost any of the functions including air/fuel, ignition timing, top speed and rev limiter. Cost is around $1000 but you do get full tuning done on a load bearing eddy current chassis dyno. This will provide not only the desired delimiting of the top speed but also give a baseline rwhp/rwtq and a tuned rwhp/rwtq. No more "guessing" that the product worked or did not work. It is offered with a money back guarantee, unusual in aftermarket circles.

Turbo][

I am seriously interested in this Unichip product, sounds alot more versitle than any products out there(besides Xede). I have contacted a local Unichip dealer, haven't got any replies yet. I hope these people knows how to operate the Unichip with the Mercedes ECU.

JunoJim

Vmax - Interesting - that's what we called the switch we put in the F-15 to let the pilots burn out their engines (destroyed in the process) to get away fast in an emergency...

BMW Dräparen

I´m from sweden and it sounds strange that cars in America dont go faster than 130-155. I have not tested how fast my car go but i know that it do at least 260km/h or 165mph.

gup998

i would go on the autobhan to test any car out to its limits...

pocholin

It is an agreement between the US and german car manufacturers, sadly!

gup998

wtf?!...didnt knw that...that sux

Improviz

The Germans limit their cars domestically as well, to 155 mph, per a gentleman's agreement amongst the manufacturers, supposedly from tire conserns. Porsche is the only one which doesn't follow this, but from what I've read that's also part of this agreement, so that there is at least one German manufacturer who competes with the Italians in top speed. I've read this in several of the automotive rags, so I assume it's on the level. I do know for certain that the all of the M cars and the AMG cars are limited to 155 not only in the US, but in Germany and worldwide, as are the Audi RS cars (although their limiters have been shown to be on the liberal side in some road tests). Supposedly, AMG does disable these speed limiters in Europe by request, but otherwise the cars have the 155 mph limit from the factory there, same as here.

However, the *other* cars in the model lines (CLK430/500, 330i/325i, A4, etc.) *are* limited to 130 or so in the US, but are not in Europe. From what I understand, the reason for this is basically because they're trying to save some bucks by putting lower-speed limited tires on those which are exported to the US, knowing that they're never going to be going that fast anyway with 99% of owners. (They put the UHP tires on the M cars, AMG cars, and RS/S cars anyway, so there's no reason to change the 155 mph limit on them.) Of course, this is still odd on a CLK430, for example, which has high-speed tires standard anyway, but that's the way it goes.

Also, some Japanese sedans such as the Lexus IS300 are not limited electronically in the US; the IS300 has a top speed of around 145, drag-limited, as does the WRX, and the new turbo Dodge Neon (forget its model designator, but it's fast!).
Similarly, the C5 Corvette has a drag-limited top speed of around 170, and the WS6 TransAms/Camaros will hit 160. The Cobra Mustangs also top 160, at least the new supercharged ones do...

And of course the Aston Martins, Porsche 996/Turbo/GT2, Lamborghinis, Ferarris, et al sold in America have no limiters, and will all top out at 170-200+.

vraa

Sadly correct! For most of us at least.

db1

A couple of other datapoints, I enquired as to the process for "derestricting" my SL55 and the procedure (direct from AMG in Germany) is simple. Show up at the factory - wait 3 hours (you can do a factory tour whilst this is going on, and even meet the person that built your engine!) - pay 2000 Euros and its done. Since AMG do it, warranty is preserved.

The std tyres in the UK market are Z rated and will run to the topspeed, which is estimated to be around 200mph. I asked specifically whether anything else was needed, the answer was "no".

You can contact AMG directly from their website - they are very helpful.

Of course if you are in the US getting your car there poses some other logistical problems...but I have heard you can remove the ECU, send it to them, pay the money and they will do this for you. I have not validated that with them though.

In the UK you can buy lots of AMGs that have been derestricted, but for some reason the UK dealers themselves won't do it. These cars are almost always imported (to full UK spec) from Europe where the dealers and AMG will do anything you ask (at a price).


DB1

ROLLINAMG

Just buy a chip for $300 and do 168 like me

ZX12R

Japanese motorcycles have reached a gentlman's agreement of 186 MPH(300KPH) which bikes are limited to. My ZX12R has the same limiter which is based off of the speed sensor, I have bought what's called a Yellow Box from a company in Australia called Black Robotics, for $100 or so it fools the computer into thinking I'm doing a slower speed and doesn't limit it. It also has an adjustment for calibrating my Speedometer for my gearing changes. I wonder if it would work for cars that have limiter based off the speed sensor? If anyone is interested just do a search for black robotis yellow box.

MB AMG

Besides the track, is there anysafe place to go really fastÉ I`ve never taken the `92 600SEL all the way to the 130MPH limiter. Here in Vancouver, there is a safe stretch of highway where you can go fast with very little cop patrol but it`s usually wet or crowded. I think standard Mercedes products should be limited up to 155MPH like AMG cars.
Anyways, how can the engines handle prolonged stress such as staying above 4500RPM for minuites at high speed. Isn`t this bad for the engineÉ

Frank Wiesmann

As far as I can remember, a 92 600SEL is governed at 155, not at 130. I think Mercedes introduced the 130 mph governors with lower performance tires in the 1994 or 1995 model year. Before then, all cars were either limited to 155 mph or did their true top speed.

MB AMG

Is the `92 600SEL limited to 155MPH I would never take the car all the way to 130MPH let alone the 155MPH limiter. I just checked the tires and they are 235/60ZR/16. Maybe I`ll try to take it to 135MPH.

Frank Wiesmann

In the Car and Driver Test it said that it was governed at 155. My 1991 300TE is also not governed. In my opinion Mercedes models before 1994/1995 were not governed at all, or in the case of the more powerful models, to 155. ZR tires are unrated, that means that the top speed one may drive with them depends on the individual vehicle weight, etc. Cars that can go 200+ mph usually have ZR tires. It is safe to go 155 if your car, particularly suspension and brakes, is in good technical condition and, more importantly, if you feel safe doing it. The W140 S-Class is designed to drive at these speeds. I you are uneasy, I would suggest approaching these speeds gradually to get a feel for them Once you feel comfortable and have a feel for hoew the car is behaving and it feels good, the nail it! Don't forget to correct your tire pressure to high speeds as indicated in the manual or gas cap. Have fun!

MercManiac

Had RennTech upgrade done to my 2004 S600. This took limiter off and entire engine is still under warranty. Had to put new tires to handle speed, torque and weight.....this is where all these heavy cars that go so fast now are having problems.....shredding tires.....hard to manufacture a tire to handle the weight.....no one has really developed a tire that can safely/statistically handle a long high speed "Autobahn type" drive......current tires can handle brief momentary spike of just trying a top speed hit and stay within safety zone.

This doesn't hold true for sports cars since their tires don't have the weight factor to deal with and without the weight this also brings down torque stress on tire.

In Germany, just a few years back, there started to be a lot of accidents....quite horrible....where the average driver was on Autobahn and flying in the new (German HP War) faster 4door "heavy" MB and BMW's....tires couldn't handle the speed and torque that went with the weight....for such long extended runs.

Yes, in the past there have been high speed heavy autobahn cruisers but this was a statistically small population and these drivers maintained their cars with the best tires available....always checking tire pressure before each drive to work with a German VDO tire guage....and always maintained a tight schedule of high speed on car wheel balancing. That said, now one's Mom can get a S600 or S55 that goes beyond supercar performance realm of just a few years back......these people don't maintain an automobile for high speed driving....and the statistical group has grown....and there are lawyers everywhere.....so.....

Hence, a self imposed agreement on top speed limits.

My only complaint is that the 600 has a speedo to 160mph...on the couple of occasions that I've run it out....I'm still accelerating when the peg stops. Would love to know the true top end on my car

MB AMG

Thanks Frank. I`ll have to check the tire pressure and put the ADS to sport mode. I wonder why the 1992 and 1993 models were the most powerful engines Do you have that magazine article on the 600SEL or W140É

MB AMG

Hey MercManiac, do you think the S600 can run at 150MPH for, oh let`s say 25minÉ I think the speedo only going up to 160MPH is stupid for cars that are capable of going higher speeds. I wonder if the 200MPH optional speedo on the E55 is availableÉ

MercManiac

I'm running staggered Y rates.....I think I'm hitting the high 180's on the top. I think it could go for 25 minutes at 180.....but would I try it for that long......no way, not that I'm scared so much for my self....but a tire shred at that speed sends your car tumbling and the thought of slamming my 4,800 pounds of car at 185 mph into oncoming minivans filled with children......

To replace the speedo is easy.....it requires switching out the entire instrumentation cluster for an AMG......you know, I'm really not sure if the S55 speedo goes to 200? Anyways I think it would be a waste of money IMO. I have asked for the new Escort performance monitor for Christmas!

BTW, sold my Z8 BMW....needed room in my garage...getting an SLR the end of Feb., will let y'all know the top end results.....and of course any kills

Frank Wiesmann

Hey MB AMG,

the 1992 and 1993 600s were the most powerful engines according to horsepower because they had a Vollastanreicherung(don't know what it is in English) ,which made the fuel richer(less lean) under full throttle. The later engines did not have this feature or it was reduced. You can go 155 for 25 minutes no problem. Remember, the top speed rating on a tire means that it can go this speed for an hour with the correct pressure without a failure. Tire tests in Germany have shown that brand name tires often surpass this rating by far(For example, some winter tires from Dunlop or Continental have gone up to 160 mph before popping even though they had a 130 mph speed rating.) Assumeing you haven't ruined your tires going up curbs tooo fast and they have the correct pressure, they will be fine.