Well...........

First off they don't spray fuel, they spray N20 which lowers the intake air temperature and increases the air density in the intake (more air in the intake), and increases the amount of oxygen the engine inhales to increase performance as the ignition splits the nitrogen from the oxygen, and the extra oxygen is what makes more power.

Fuel enters through the fuel system/fuel rails, then via the fuel injectors, which sprays the fuel, similar to an aerosol can, into the cumbustion chamber.

Secondly, ALL N2O systems need some rate of tuning. Basic dry kits running less than a 100 hp shot can go with only the ignition control kit or window switch that comes with the kit, however wet systems, and dry systems running larger than 100 hp boost need tuning to keep everything in check across the power band.

 

Actually it does spray fuel if its a wet kit....

 

Well that depends, some wet kits still spray in the air intake tube (which is not mixed in with the fuel), only the direct port wet kits spray a mixture of N2O and fuel as they mix the fuel and N2O near the fuel rails, but I highly doubt he has one of these kits.

 

To my knowledge a "wet" system is the mixture of both nos and gas and injected at the same time into the engine.

Where as the "dry" system just sprays it into the air intake side before it hits the engine.

So I am repeating what jthorn9 said. And my 2cents are that if you use either setup a tune is a really good idea so that you don't over lean your engine or anything.

I can see how tuneing a F/I car with nos would be hard but I hear/see cars with that set up every so often so its not impossible, and a great mixture of 2 power adders if done right.

 

im not sure about heads being different with FI but for the cam, you just dont want as much overlap as you would with N/A. with larger overlap and FI the exhaust valve will still be open a little when the intake opens, essentially losing boost thru the exhaust. if you talk to the company you want to buy a cam from they can tell you everything about it and set you up with the right cam for your setup

 

+1 get a rear end.
my opinion, go 8.8. your 7.5 wont break because you will never get traction on stock tires

 

dry kit sprays only nitrous

wet kit sprays nitrous and fuel into the intake

direct kit sprays nitrous and fuel into each cylender

 

You may wanna brush up on your nitrous knowledge.

 

How much does N2O cost?

And now I know that there is a third version. I LEARNED!!!

 

Well there you go, hey we're all allowed a brain fart or two (insert old dumb founded sticky).