whatever the needle stops at with your foot on the floor and it stops accelerating
A stock SHO should be able to hit 155 mph, if REALLY you hammer on it you could get up to 160 but not much more unless you're going downhill. If you put money into it like cams and an intake and all that happy horseshit you can get it moving quite a bit quicker...Mine tops out around 180 mph so there's an example for you.
I forgot one thing in there though...If you max out your car you risk blowing the motor alot since the car runs high rpms in the first place.
V8 SHO's are limited around 143 mph. Anywhere from 140-145 the ignition will cut out. There's a lot of factors involved in getting a 12 year old car up to that speed, though. If you're gonna try it, be careful and make sure you have back-up transportation!
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