I finally did it.
 

The W126 will go 150 mph and will cruise there smoothly, infact, it feels even smoother at 120+ than 75-85 mph. Take it up to 115 and punch it, and there is still plenty of power left to shoot it up to 140 and beyond that. At top speed, the car is nice, controlled, and the MB W126 supurb suspension really shines here and the 560SEL's engine lets you know that it's a 5.6 V-8 and is no slouch. Makes me want to get sports performance tires on it. There's nothing like doing 140mph in a two ton beast of a car and still maintain the comfort, quietness, and refinement. I'm never selling this car.
On paper it says this engine only have about 238hp. Who is Mercedes fooling? They rae being too modest ain't no way that it's only 238. I've driven plenty of cars that have 300+hp and don't feel nothing like or as powerful as the 560SEL and let alone that most of them are computerized to hit something like 120 or something if ya lucky.
Do anyone know the true stats of this 5.6 W126 engine?

RE: I finally did it.
 

Sweet thank u for finding this out i always wanted to be able to say i owned a car in the 150 and up club and thanks to u i know i have one. Ur next mission is to mod it and see if u can get 175.Or maybe a 200 mph W126

RE: I finally did it.
 

well they said to add straight pipes (slightly more throatier exhaust note, increase compression from 9:1 to 10:1, convert the 5.6 into German AMG specs and boom it's 175. 200 mph, there was one guy who had a super charger built for the 5.6 AMG engine and was rumored to be able to reach 200+ on a straight way, but this was a while ago and the mods he did cost a small fortune.

Just as most people don't know that there is a Super charger kit built for the 1995-2001 BMW 750iL V-12 but it cost no less than $14,000 just for the basic kit.