Has anyone tried to reach the top speed on the GS400? In magazines, they say the top speed is at 149mph, but I dont think that's right. I have gone as fast as 143mph and all of a sudden I think I reached the limiter and my car doesn't seem to go any faster.

 

Your 18's might throw your speed off a little bit. I topped my car at 137 and it supposed to be 144. I also have 18's on my car. Speedometers can be innacurate at high speed too... So you could of really been going 149...

 

Actually, I tried this before and after I got my 18"s and the top speed was about the same, around 142/143mph. But your right, I noticed I lost a little edge on the acceleration with my 18"s.

 

You will notice is slower acceleration because your 18" has wider tires and the contact area is wider too. That's the draw back. The gain are your cornering speed and stability. Take your pick. I rather take cornering speed and stability.

 

I have the factory 17-inch wheels on my car. I went to 144mph. There was some traffic and I had to slow down. I am sure I could have gotten 149mph.

 

I have taken it to 141 and then backed off. It still had some pull left and without question I could of taken it further. I do not recommend any speed over 110 in this car stock without some suspension upgrades. After the LTune upgrade I took it back up to 140+ and it felt much more stable though still some wandering. Sway Bars and a alignment should take car of this. Taking into account all factors including stock 235/45/17's this car should reach at least 156 if not for the limiter in stock form. I have gone 143 (maxed out, 58 degress,2300 ft elevation) in my 92 SC300 and 145 in my 93 SC400(let off) and the GS400 had more pull left in it. This car is actually capable of doing 205 if by gearing alone, though it would take about 600hp and 500 lbs and alot of empty road to accomplish this.

 

with 17's my friend did take it to 149 on I-5. The fastest I've gone was 148 but I'm running 18's. The top speed might be 150 if running with the stock 16's.

 

I went 140+ one time, and the feeling at that speed left me thinking the car could have surpassed 149. I realize that it is limited, but I think minus the limiter, a GS400 might eclipse the 155 mark....not that I would ever attemp it... Tiny

 

I raced a mercedes SL500 AMG when I first baught my car and I toped it out at 155mph I think my speedo could have been off because as stated the car shouldnt go faster than 149mph but I was on his tail ( about a foot away at all times) till I slowly started pulling towards him and you should have seen the look on his dace when a sedan passed him at 155mph and I was pulling away from him I know the sl500 has a governer of 150mph so some one please explain to me this fanamonon and we were on a flat serface at the time of the race on I-5