NOS in light doses Does not harm a motor if the motor is in GOOD condition.... However, it gets addicting to the right foot...... You can set up the NOS to hit light so you don't get the Wham effect that most dragsters want.... Putting the NOS valve farther away from the Motor and the Fuel valve next to the Intake lets the Nos come on soft and gives the motor time to load up a bit on fuel (1/10 of a second or so) before the Nos hit the chambers. It does confuse the crap out of the O2 sensors and EFI making the motor try to run lean, because it sees a rich mix coming from the motor so the engine management cuts back on the injectors.
Yes you can put NOS even on your MTD riding lawn mower, but for what reason? NOS is for top end power, your motor was built for a low to mid range power band. it is not a high end motor from the word go. NOS puts some strain on the pistons, rods and crank. We will leave Transmission, Transfer case, u joints and Axles out of the picture all together this time.
If I was you.... Heck yes I would do it.... But that is just CUZ I is a red neck at heart!!!!!!!!:mrgreen::twisted::bomb::drunk:
Have a good Turkey day weekend dude!!!!!