Note what has been said about automatic transmissions. Your transmission software does not know about your N2O setup, and when it begins to approach redline it will shift, allowing all of the power your motor and the additional power generated by the nitrous to be run through your torque converter (since you don't have a clutch). I have on more than one occasion seen a weak honda torque converter get its goose cooked (although honestly, it's more often a problem of burned valves with the "gas").
- Mazdaguy