Wet NOS with EFI - A couple of Questions

I am looking at putting together a wet nitrous system for my EFI 502. The configuration of the manifold and throttle body is very similar to a LT1 except it uses an Alpha-N (like the ram jet crate engines) with no MAF, no SD, and no O2. The injectors are 36 pounds and fuel pressure is regulated at 42 pounds. I am looking for 200 HP.

A couple of questions for the EFI nitrous gurus....

1. My throttle body is a dual blade - should I use one or two fogger nozzles?

2. Can I inject right behing the TB or do I have to go through it?

3. What do you regulate the fuel pressure to for the fogger nozzles?

4. Does anyone have the HP and jetting per nozzle?

5. If I do use 2 nozzles, is it fair to double expected HP or are there losses to take into account like with dual carburetors.

I appologize for the simple questions. My history with nitrous has been carbureted plates and foggers. This engine and my MTI 396 LT1 are next in line for the bottle and I am trying to get a handle on the options.

Thanks
Adivanman

1. My throttle body is a dual blade - should I use one or two fogger nozzles?

Either will probalby work. I am using a twin nozzle setup.

2. Can I inject right behing the TB or do I have to go through it?

Best injected in front of (upstream) of the TB to get more even distribution.

3. What do you regulate the fuel pressure to for the fogger nozzles?

A wet system is designed to run at stock FP. If you want to make it richer or leaner you change fuel jets..

4. Does anyone have the HP and jetting per nozzle?

Any kit will have a chart. This is a nice on line calculator http://www.robietherobot.com/NitrousJetCalculator.htm as it include the key variables of nozzle size and fuel and nitrous pressure.

5. If I do use 2 nozzles, is it fair to double expected HP or are there losses to take into account like with dual carburetors.

Yep, twice as much nitrous = twice as much hp.

Rich Krause

Thank you Rich.

Originally posted by adivanman
Thank you Rich.

You are most welcome! But I meant to point you to http://www.cosmik.org/calculators.htm which is a better jet calculator. It tells you the correct fuel jet to use with a given combo of nitrous jet, and fuel and nitrous pressures.

Rich Krause

Rich,

Is there are ideal distance in front of the throttle blades with a wet system? When I spoke to NOS about a dry system, two different techs told me everything from 6" max to 12" max. I would assume that a wet system would prefer a straight shot.

Also, does anybody have any experience with throttle position based WOT switches vs. conventional micro switches? I have hear that the TP switches exist but have never encountered anyone using one.

Thanks again,
Adivanman

The distance that NX gives for nozzle placement is 2-6" before the throttle body. I have sold quite a few of the TPS switches and I haven't heard anything but good things about them. If you would like a price on a NX nitrous system let me know and I will be happy to get you price. I am currently overstocked on the EFI Race systems that are adjustable from 100-250hp and I could make you a great deal on one! Thanks

As Steve said, 2-6" seems reasonable. 2" seems kind of close to me. I am not sure why a TPS switch would be better. No problems mounting it, I guess? No personal experience with them though.

Rich Krause