Jspec350z

iTrader: (3)

I wanted to find out what jets anyone running either zex, NX , or Nitrousworks systems. I have been doing some research and Zex will not give me answers. Here is what I have so far.

Max's zex kit
52/26 = 100 shot

MySunset350Z NX kit
35 shot 31/18
50 shot 35/20
75 shot 41/24
100 shot 46/28

Edretti
52/26 (125hp) said lean

Please post your results!!

Jspec350z

iTrader: (3)

Here is Zex's Recommended Jets. I basically just took their formula and carried out. Do these work? Just in the ballpark?

Edretti

Well, you definitely hit it on the head! BALLPARK! 02trex and I have been experimenting with jets for quite sometime now. He's usually the leader and I'm the follower. He just told me that he went to 73/43 and is expecting about 150rwp. He had 73/40(which zex told us would be 200 shot) and put down 140rwhp but he was slightly lean. He is going to re-dyno soon. I'm currently running 54/30 (150 shot) which is about 117rwhp. All we know is that Zex overstates there hp ratings for those jets. There listed 210whp is 82/46 but who knows. Not sure that I am personally going to find out either. Hope that helps!

Jspec350z

iTrader: (3)

Cool this is exactly what I needed. Thanks for the info!! ANy additional RWHP #'s you have got would be very helpful. Also where are you getting your jets from?

HP Shot----Nitrous----Fuel
150hp-------73--------43
140hp-------73--------40
150hp-------54--------30 117rwhp
210hp-------82--------46

Edretti

I get them directly from zex.

Jspec350z

iTrader: (3)

Is there any difference in a nitrous jet and a fuel jet ? or are all jets the same? I have the following jets for now 19, 21, 21, 28, 31, 36, 40, 52 so for now I am thinking 52 nitrous 28 fuel around a 100 shot ?

Edretti

No, the jets are similar in apperance but they are different. The fuel jet has an inverted cone shape tip and the nitrous jet is flat. So anytime you say 52/28 that means nitrous/fuel jet. And 52/28 is actually a 125hp jet. I was running 52/26(too lean)then jumped up to 54/30 which is great and zex estimated 150hp which is actually 117rwhp. I have yet been able to figure out their formula so I gave up a long time ago.

02trex

Here is the best I can help:

Nitrous---------------Fuel-----------------Actual WHP
52--------------------- 28 ---------------- 90, good a/f
54--------------------- 30 ---------------- 117, good a/f
73--------------------- 40 ---------------- 140, lean a/f
73--------------------- 43 ---------------- 150+ (tbd), good a/f

There is no exact science to this, and each manufacturer states different jetting recomendations, all of which indicate fuel jets that we have thus far found to be on the slightly lean to dangerously lean side.

Please note that spark plug heat range and gap, fuel pressure, and bottle temperature also play a role in determining jetting for proper a/f.

Edretti

I agree, I'm running one step plugs and 02trex is running 2 step. Our fuel jets will certainly be different although slightly. I certainly agree with the bottle pressure. Some guys on here aren't running a blanket. This will certainly change the a/f. Like I've always said, what is good for me may not be good for you. Not two engines are exactly the same. With any nitrous application a dyno should be run after jet changes. I almost learned the hard way.

Jspec350z

iTrader: (3)

I wonder if the fact you guys both have g35's matter. I will be running an injen intake and Crawford Plenum also. That should further lean things out. I am going to try 52/28 for this season. Maybe in the spring I will hop on a dyno. I would be happy with mid 12's hopefully next week.

cyberz350

iTrader: (3)

Hate to start a new thread, so, you guys are dynoing to find the wheel h.p. right. How does that actually work, what gear do you spray in, and do you spray all the way to redline? I want to make sure I'm not running lean. Whats the A/F ratio I should be aiming for.

12SecZ

**:105hp------52--------27**"

Hey Jason long time no see hope all is well with you. I used NX Jets. ZEX said 52/25 for me but I couldn't find a 25 so used a 26 for fuel, figured better fat than lean. Ran a 12.7.

Good Luck!

mjedens

iTrader: (3)

We dyno to find the RWHP but more important we are doing it to check the A/F ratio. I would love to be below 13.1 thru the whole rpm range. I would suggest using 3rd gear for the simple reason you won't have to spray as long!! (I usually tune on a Mustang Dyno- doesn't matter what gear you are in and my Mustang tech is sharper than the Dyno Jet guy. If you need numbers to compare to others on this board- use a Dyno Jet. I only use a Dyno Jet when doing "motor only" pulls. The numbers on a Mustang are typically 15% ""less"" than a Dyno Jet.) I spray between 3000 and 6950 , 7200 being redline. Be sure & not hit your rev limiter if at all possible when spraying!

cyberz350

iTrader: (3)

Thanks for that explanation mjedens, that clears up a lot. Couple questions though,

Will I get the same air/fuel ratio whether I pull in 3rd or in 6th?

Whats the range for A/F ratios, as in where is it rich and where is it lean? Is 13 just right?

And if I dyno, and realize I'm running a bit lean, do they let you switch out the jets and run again?

Thanks

webcarconnection

I susgest you spray in 4th or 5th if you want to see the real whp of your car... to clear you up about the A/F the perfect range is 12.0 to 12.9 (perfect meaning "safe") the A/F may not be the same on different gears but just a little bit! (if the # is higher more lean the car is... example, 14.0 for nitrios cars is to lean!)

And if I dyno, and realize I'm running a bit lean, do they let you switch out the jets and run again?

They sure do!

mjedens

iTrader: (3)

Webcarconnection is correct about having it in 5th when dynoing on a dynojet!! (that is the correct gear to get the most accurate #'s on a dynojet) I would also love to see 12 to 12.9's, I've just never been able to get my whole rpm range down there. Switching out jet sizes is what it's all about when trying to tune with N20.

cyberz350

iTrader: (3)

thanks guys, I just wanted to make sure I knew what I was doing when I go dyno my car, that way I don't waste money. How much are you guys paying to dyno tune your car?

12SecZ

$65.00 is 3 runs, you are better off paying a flat rate for one hour, it's not much if you get a square deal.

My A/F was under 13 with the 52/26 and gave me about 100 to the wheels in 4th. Lots of variables such as bottle temp/pressure etc.

webcarconnection

My A/F beging on 13.0 and end on 11.7, so the 12.0- 12.9 range is a little hard to get on the whole rpm range... but 12SecZ is correct lots of variables such as bottle temp/pressure etc.

MySunset350Z

iTrader: (23)

ill will be doing a dyno come march. i counting the days. a bunch of bolt-ons to be added too most arnt for the engine though, BUT a few are. mmmmmmmm, cant wait.

Jason, any new updates on your n2o situation?

i just found out today that my jets wont be coming in the mail ne time soon, soo ill just have to go to where i got my kit and get them there. this of course means imma have to wait til march to get them. bla