I went dragracing yesterday and experienced some problems, this was the first time I was going to run 150 shot nitrous with my Nitrous Express wet system. I have been running a 100 shot all summer and it has been working fine.

I satged in and went for it off the line and the car hooked fine and I started spraying at 3000 rpm in first gear and the car went away really great UNTIL I reached 75 mph then it just died and started "bluddering" and all power disappeared and the car started "notching" as when you run out of fuel...

I thought I for sure had blown the engine but when driving back it seemed OK again and after a short examination I decided to put back the 100 shot nozzles that have been working great all summer and give it another go.

So the next run I go off the line with 2,060 60feet time and sprays at 3000 rpm as usual and the car runs as great as ever and I do 12,341 and everything is back to normal again and the car went great all the way back home. I used common road tires (Yokohama AVS Sport), that is why I only managed 12,341 with a 100 shot. (had to explain...)

Why is the car not running good with 150 shot in higher speeds, it seems OK up to 70 - 75 MPH?

The engine is completely stock except for a Donaldson Blackwing filter and a Supersprint exhaust. I have NOT retarded the timing at all but the car was not pinging. I run common 98 octane fuel with NOS black octane booster.

Which nozzles do you guys use when spraying 150 shot, my dealer told me to use 41 for the fuel and 62 for gas, do you guys use the same nozzles. I have seen another list that says 38 for fuel when spraying 150 shot ????

One theory has been that the car got to much fuel but I don't think so since the car goes great up to 70 MPH...

Have any of you had similar problems or do you have any ideas of why the car is behaving like it is? I would be very greatful for help and please write which nozzles you guys use when spraying 150 shot.

Thanx in advance

Tommy

 

Well if you like my opinion..........I wouldn't run 150 on a stock motor. Thats just me, other people might tell you is ok. If I was you I call NX on Monday and ask them the correct jets sizes for the 150 shot. If your motor is stock, I would ask them for a 125 Jet size and try them, I believe thae 125 might work better.
Also, I would change the window pill to 3200 instead of 3000. Once again thats just me............ok :thumbs:

 

NX JET CHART FOR LS1 & LS6 -------100 HP 52 NITROUS / 31 FUEL-----------150 HP 62 NITROUS / 33 FUEL . :seeya

 

JOHNNY P

Yes, I know perfectly well what the sheets say, the problem is I have seen 3 different sheets so which one is correct?

Which nozzles are you using? Do you have personal experience from your figures and how are they working in that case? Please inform me I am very curious.

Regards

Tommy

 

150 shot is no problem on a stock motor,also, 3000 is perfect on your window switch, you can even go 2800.Did you try the 150 jets again after you made a good pass with the 100 jets? Sounds like you may have had the nitrous solenoid not come on, it mat have had something in it, if the fuel solenoid worked, you were just dumping fuel into the motor, and that would cause it to fall on its face.Make sure you have the right jets and try it again. When I was stock I used to run 150 shot, with the window switch set at 2800-5800, and never had a problem, probably used 100 bottles through it. :cheers:

 

kwik8racr

Thanx for the info. I am sure that both solenoids opened since they are both connected to the same fuse and it was OK. I did not make another pass after the successful run with the 100 shot since the dragstrip closed for the day...

I think I had a too big jet on the fuel, I havé sent an inquiry to Nitrous Express to get back to me if my datasheet is wrong... I suspect so...

Thanx

Tommy

 

You problem is fuel related. LS1/6 intakes were never designed to flow fuel. I would check your fuel jet. Before you run the 150 again, I would put in on a dyno and check your air fuel. The Nx jetting is pretty conservative, so we dont pop our motors.