Written by laughin2.2
PreludeOnline Moderator

Can I run nitrous on my car?
Nitrous can be run on pretty much any car, whether it be stock or a fully built NA beast. If you have an older car or one with many miles on it, you will want to run a compression check. The numbers for each cylinder should be pretty close to each other and within Honda specs. For example, if you had 240, 238, 242, and 245 on a JDM H22A then it would be safe to run nitrous on that engine.
Secondly, aftermarket chips, ECUs, and Venom control modules that advance the ignition timing are not safe to use with nitrous. You may be able to use an MSD ignition timing controller or a Jacob's nitrous mastermind to retard the timing only when you are spraying, but it is very important to follow the rules for retarding your ignition timing when you are spraying nitrous. I will discuss these rules later in this post.
Finally, nitrous loves high compression, but the nitrous fuel ratio has to be tuned very precisely. 100 octane fuel will make it much easier to run high compression and nitrous, but it can be done to an extent on premium pump gas and good tuning.

Dry, Single fogger, and Direct Port: What's the difference?

Dry Kits
Dry kits have a single nitrous nozzle plumbed into the intake tube(Mount the nozzle at least 6 in. from the TB) and they only spray nitrous into the intake. The extra fuel is provided by the injectors, when the ECU notices the extra oxygen molecules in the intake air charge. Dry kits can only be jetted up to a 75 shot because the nitrous is not distributed evenly to each cylinder. The injectors give an even amount of fuel to each cylinder, but because some cylinders are getting more than others you will get a dangerous lean condition in that cylinder. Running lean leads to predetonation, and predetonation is what blows motors.

Single Fogger Kits
A single fogger kit has one fogger nozzle mounted on the intake tube(Also 6in. from the TB). However, both fuel and nitrous are sprayed through this nozzle. This kit has a fuel solenoid and a nitrous solenoid, where the dry kit has just a nitrous solenoid. The idea behind this kit, is that spraying fuel with the nitrous will fix the lean condition that plagues dry kits that are jetted above a 75 shot. The problem with this is that fuel is heavier than nitrous and therefore it won't be able to make the turn to the first cylinder after the TB as well as the nitrous does. Honda intake manifolds are biased towards certain cylinders, which will still give uneven nitrous and fuel distribution when usinf a single fogger kit. Some people swear by these kits, but personally I'd rather plumb in a direct port kit for anything higher than a 75 shot.

Direct Port Kits
Direct port kits spray nitrous and fuel through single fogger nozzles on each intake runner. This is the only kit that can provide perfectly even nitrous and fuel distribution. This kit incorporates one nitrous solenoid and one fuel solenoid, just like the Single Fogger Kit. The only drawbacks to this kit is that it is hard to hide, and impossible to hide from someone who knows alot about nitrous. Also when you want to increase your shot, you have to change 8 jets as opposed to two on the Single Fogger Kit. A direct port kit can be jetted to as low as a 75 shot and to high as your motor can hold (Providing your solenoids can flow that much nitrous and fuel)

What do I need to run X shot?

First of all, you must always run premium fuel(91+ octane).

50 shot
All that you need is a set of one step colder copper NGK plugs or a set of Zex plugs(Two steps colder than stock) and you can keep the ignition timing at the stock timing.

60 shot
You need the colder plugs and you will want to retard your ignition timing by a degree or two. You may want to look into getting an aftermarket ignition and spark plug wires.

75 shot
Retard your ignition timing by 3 degrees, pick up an ignition, colder plugs, spark plug wires, and look into getting a stronger clutch because your stock one will be slipping very badly. If you find that you are running lean or rich pick up a fuel pressure regulator. If you are running a direct port kit, then you can pick up an Apexi VAFC to control your fuel map.

100+ shot
While you can get away with running a 100 shot on a stock motor, I'm not going to recommend it. If you plan on running any shot higher than a 100 shot, you will need to beef up your bottom end. Forged pistons nd forged connecting rods are the first step. I have heard that it is necessary to resleeve the block in order to run forged pistons on H22As. Whether you believe this or not, is up to you. I figure that if you are going to build a block, you may as well go all out and resleeve it as well, but that's just me. Everything that you need for a 75 shot you will also need for a 100+ shot. It will also be necesarry to upgrade your fuel pump to a 225 lph pump. Walboro, NOS, and Holley are all good choices for fuel pumps. A preogressive controller will also be necessary to control the nitrous flow, so that you don't smoke the tires for the first 1/8 mile. NOS, NX, TNT, and Jacob's Electronics all make nice progressive controllers. 2 step colder plugs will help ward off predetonation, and it will be necessary to retard the timing 2 degrees for every 50 shot.

What brand should I get?

NOS
NOS has been in the nitrous buisness for many years and has made a very good name for themselves. They produce single fogger kits, direct port kits, and dry kits. If you need a new solenoid, a nitrous line, nozzles, distribution blocks, etc. NOS will make a replacement part.

NX
NX is very similar to NOS. It is a good company, that makes quality parts, and they have been around for a while now.

Zex
Zex is the simplest dry kit that you can buy. The nitrous solenoid is housed in a purlpe control module. This makes it an easier install, but it also makes it so that you can't buy little individual parts to fix your kit, such as solenoid plungers,springs, etc. like you can with NOS and NX.

Venom
Venom is an expensive dry kit. It incorporates a computer program to control the nitrous flow and it also uses a program to watch your AF ratio, so that you don't run lean. The reason that I don't like Venom, is that you can only jet a dry kit up to a 75 shot, so you you don't put down enough power to have any really big traction issues. Basically, the computerized nitrous flow controls are unnecessary. Secondly, a fuel pressure safety switch from NOS and some dyno time will provide just as much insurance that you won't run lean as the Venom kit, and it will do it for cheaper.