You haven't said anything about w116's yet, so i will. I've had my car to 100mph 3 different times. All I can say is that I wish there were more areas where it is safe for me to do this. Once was in Virginia and the other on a local interstate at a bad time. Won't say where the third was since I'm only 18 now I'll have to wait till I'm about 80 to tell that one. Anyways, my car handles it BEAUTIFULLY! It is tight and turns almost exactly 4000 rpms at 100. When I did it once I had 3 other people with me and no one said anything till I said something about it. They all commented on how solid it felt. We had all the windows open and the sunroof so I couldn't hear my diesel roaring under the hood. Since then I have replaced the ball joints and upper control arms along with other associated bushings, but I haven't had any opportunities to take it over maybe 80. My car weighs around 4900 pounds though so it is definitely heavier than yours.
I have had my dad's up to even higher speeds and that was just stupid of me becasue it was vibrating over 90. From my father's example, which I think needs some underbody work, mine is definitely a better high speed car. Sure it doesn't have as much power getting there, but it would surprise you how fast my car really is once it's underway. One more thing, your car has 125 hp and mine only has 110 hp. Don't know what was changed but I can say that I had a better experience getting there and staying there than you did.
Thanks
David

P.S.
Please think about what you are doing before any high speed runs becasue of safety and police. I did mine with new tires and I was confident in my car which I knew was in good condition underneath. Unexpected things do happen and they happen much faster at 100 than 55, so PLEASE, USE YOUR HEAD.
Thanks Again

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2000 Honda Accord V6 137k miles

1972 300SEL 4.5 98k miles

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