[hotrod]

I'd also be inclined to run a separate system for the nitro. Much better control that way, you could only spray the nitro at certain times to cut the costs etc.

I would be inclined to always use a methanol nitro mix for the simple reason that that would give you a handy means to tweak the amount of nitro your using by changing the mixture rather than changing the spray jets.

If I did it I would probably also go direct port injection to ensure the injection rate was balanced between the cylinders. I'd also keep a WI system setup to manage any detonation/ heat load issues the nitro may create.

My instinct would be to trigger an additional WI spray jet along with the nitro until tests show it is not necessary. (I like to take my time and work up slowly and methodically on radical changes like this)

I suspect that at high usage rates detonation could be an issue so would want to keep a little WI reserve capacity available.

Ignition should not be a big issue as you have normal fuel combustion to light off the nitro.

Keep in mind this sort of settup will share some characteristics with a nitrous system. For example if you spray the nitro at low rpm in a simple on off type system you will spray more nitro per engine revolution than you will at higher rpm. That would have the effect of automatically cutting back the flow of nitro at high rpm.

In a system that tracks the injector duty cycle you would have a more rpm independent rate of injection..

Larry