Finally got to put my car on the dyno with the NX 100 wet shot. Gained only 50 and was very rich. Last year my buddies 150 shot dynoed 78.

I thought NX was rated at the wheels? This is total BS!

 

Something seems very wrong. When I ran a single nozzle 100 shot I gained 98 rwhp on my stock motor and my buddy with a 2002 Z28 gained almost the same (I believe 96 rwhp) on his single nozzle NX 100 shot. We both ran a little fat with an 11.9 A/F on the juice (A/F ratio 12.7 NA). RWTQ gain was almost 150 at the spike. What was your A/F ratio and what were your jets? Also what fuel pump? What spark plugs? What was the bottle pressure at before and after the run?
Start with the basics and maybe something will come up. Hopefully this info can help "us" help you!

 

A C5 Coupe? yea, if it's the mods in your sig you should get close to the 100hp mark. Like Airwolf stated more info is needed, and surely someone can help you figure this out.
Robert

 

Jetting- 52-31

Plugs- Autolite AR12

A/F ratio. 13-1 n/a ,, 11.4-1 with 100 shot

Bottle pressure 950.

Stock fuel pump. If I was running out of fuel, I believe it would have leaned out.

 

Jets are correct 52 nitrous and 31 fuel. Bottle pressure is actually low. NX wants to see a starting point of 1050psi, usually dropping to 950-975 after a 1/4 mile run. Plugs you are using I am not sure on, but Autolite AR472 or TR-6 may be a better choice. Did you see any KR on the run? Maybe that could pull enough timing to give low numbers if the plugs caused a problem...
I wanted to know about your fuel pump incase it was actually putting out too much fuel pressure causing the fat condition. I did not believe you were running out of fuel, but really the opposite occuring if the pump was not stock.
My "suggestion" would be try it again with the bottle pressure up and then if still low maybe a 29 fuel jet. Also, pull your jets and make sure there is nothing possibly clogging the nitrous jet. You never know. Are you running a nitrous filter? Last thing make sure the nitrous feed line is not somehow crushed and restricting flow. I know these things sound basic, but again you never know.
Hope something helps!

 

My plugs are a different number because they have shorter reach plug than normal. A cold plug (about .300 shorter thread) (TEA Heads were worked this way)

Timiming was set at 26 degrees. Seemed to not effect the N/A power and was rich with the n2o.

No Knock retard.

I was thinking about going to 29 fuel jets. I was wondering how much it would change the afr. I wont be able to dyno it again in the near future.

Was also thinking of just putting the 150 jets in since it wont put out the 150 hp in any case..

Hmmmmm

 

wow....that is low...im running a 52 n 28 f set up per the nx book???

 

You will get richer as bottle pressure goes down. You need to log a/f with he correct bottle pressure as a starting point. However, even being a little rich like you are should not cause you 50hp? Check the things suggested and keep us informed.
Seems none of the dyno operators know anything about tuning anymore?
Robert

 

Robert

The dyno operator was not asked to do any jetting changes. Why should they have to? Why should I have to pay for a dyno tune to make something work? That was not the purpose of my visit. I was just curious. I did it as a last pull.

NX advertizes this as a 75/100/150 kit. A bottle heater is an option. (I do have one though)

Funny how none of the NX dealers have jumped in. I have a hard time believing this is a "rare" occurance. (2 for 2 in my area) I would bet most people with NX systems never dyno their cars and really don't know they ae getting short changed.

You feel a difference with the shot. What you feel and what you get are far apart.

Just another overstatement by our trusted dealers!!

 

Any idea how much will dropping the fuel jets that much effect the afr? My book calls for 31s. Thats what Came with the kit.

 

Try 52 and 28. I think that 31 is a misprint in the chart. As already stated, you "should" be getting ~100 rwhp from that 100 shot. Most everyone does.

 

Sorry i dont believe its nx fault, plenty of people have dynoed their cars. Could you post the graph and if you cant how much torque did you make. What is done to your motor as far as H/C.

 

IMHO,, What I have done to my motor should not be an issue . A 100hp gain on a 300hp motor s/b the same on a 500hp motor.

Is the consensus the jetting I was given with my system is wrong? Are the fuel jets the wrong size? Is dropping to 28 fuel jets safe?

Thanks

 

Everyone's book says 31 for that one model year group and I asked about this myself and was told to ignore it and use the 28 jet for the fuel. No, I don't know how much of a difference it makes, but I'd start there.

I can tell you that when I dynoed mine, I got what I paid for and if you do a search you'll find that there are tons of positive, verified results. NX didn't get its reputation by accident. As far as wondering why NX hasn't jumped in on this, do you think this might just possibly be because you posted your problem on a Friday night?

 

I agree. Bone-stock or modded, a 100 shot should be a 100 shot (and with NX kits, it normally is).

 

Excellent point Steve, I guess I am not giving NX a fair chance. BUT,,, My friends 150 shot dynoed an additional 78hp on his C5. I just feel its too much of a coincidence.

Must be the air up here??

 

I can't answer that one for you, but if you're at an altitude where there is less oxygen in the atmosphere to begin with, maybe you have hit upon something? I'm not smart enough to know this one.

 

Steve,

I was making some humor! This was dynoned almost at sea level. I see you are from PA. Are you going to the Corvette Challange on 10/22 at Englishtown?

Vinnie

 

100 shot is a 100 shot good one! Anyhow how much torque did you pick up with the botttle. It may have something to do with the convertor to.

 

Torque was up 75. I am going to change the fuel jet I guess.

Whats the worse that could happen??