Thunderbolt Tuning Chip manufactured and sold by Chip Your Car specifically for the 450 Smart.
I have tried them all over the years since my car was new. Started with the Sprint Booster (my opinion it didn't do anything), then with the Go-Pedal (my opinion didn't make any difference either), and then tried one of those Chinese Knock Off Chips for just several dollars (again, my opinion it didn't do anything). Then I bought the Thunderbolt Chip, but not until I did a lot of research and a lot of talking back and forth with the Chip Your Car People. They convinced me, so I bought the Thunderbolt specifically for the 450 Smart for $229.00.
It made a tremendous difference.It did everything Thunderbolt said it would do and has improved the performance of my car, took away that "wire conductive lag you would experience once in a while", and it strung out the shifts in the gears to really make the car rip. It is one of those Chips whereby you have to leave it in the car for a little while until it sets the ECU with the type of driving you do with your car. Believe me, I will contest that it works because I have had my car since new and it is my daily driver. Therefore I know all the ins and outs and what the car can do with or without improvements.
I'm asking just $18 for the chip (shipping included in the continental US). http://www.smartcarofamerica.com/forums/attachment.php?attachmentid=36778&stc=1&d=1515628718
