mrr23

just completed a 9 nozzle shootout. tried out each one with the same .062/.033 jet. then changed only the fuel pill to try and match a/f ratios. 78 graphs are up. went 24 miles on the dyno, did 21 pulls, used 13 lbs of nitrous.

here's the results:http://www.centralfloridastreetcars....eshootout.html

TMoNeE98

Mods, sticky this... mrr23 is a great guy and did his homework. Excellent testing!!!!

mrr23

thanks for the kind words.

2000GTP

Very nice and thorough writeup.

mrr23

thanks

walt355

Good stuff, thanks for sharing

srsnow

Did you use the the manufactures jets with each nozzle? e.g. NOS jets with NOS nozzles, TNT's jets with TNT nozzles.

Injuneer

I'm still trying to interpret the data. There's a huge amount, and obviously a huge amount of time invested in the testing.

It would appear that the results are masked somewhat by the variables in A/F ratio. The best way to look at it seems to be by looking at the pulls that were close to 12.5:1.

At first glance, the NX SHO stands out because of the high HP rating, and relatively low nitrous consumption. But look at the NX Shark..... seemed real promising at 13.0:1 and was richened out by cutting the nitrous. End result was within 4.2HP of the NX SHO, but it only sprayed 7.75/8.75 (88%) of the nitrous. If the A/F ratio had been corrected by increasing the fuel jet size, the nitrous rate would not have dropped to 88% of the NX SHO flow, and it might have made more HP.

Seems like there are so many variables.... A/F ratio, nitrous consumption, etc that there needs to be a regression analysis to extract the affects of the A/F ratio variation. Then the nitrous flow needs to be equalized for a direct comparison, indicating how well the nozzle uses the nitrous that it is fed.

mrr23

used the same NX jets in each nozzle.

mrr23

the column of graphs on the left were results of just swapping out the nozzles regardless of a/f ratio. the column of graphs on the right were jetting the fuel side only to try and match the a/f ratios at 12:1. it looked closer on a 14" monitor without expanding the a/f graph. once i got home and started making graphs, i started to see how far off i was.

the a/f ratio was correct by increasing the fuel side only. the first pull was the baseline .062/.033 the a/f ratio matching was .062/.038. it's written on the graphs. all runs were on the same .062 n2o jet.

http://ls1tech.com/forums/showthread.php?t=487826 original thread that got it all started.

srsnow

If I rember right the NX jets use a fatter stem than most other companies. Unless you took the jet fittings out of the NX nozzle and swapped them around. Or did NX go to a normal style jet?

mrr23

both nos nozzles and the dynotune nozzle had to be drilled to fit the nx jets. all the others already accepted the nx jets. dynotune was the only one i modifed. the nos nozzles were modified by nos themselves and then sent to me. the only thing done was enlarge the stem area to fit the jets.

srsnow

Not suprrised the NOS B nozzle (the black one) preformed so bad, it never did flow well past a .040 jet in any sort of real world application. on paper it has almost the same flow as a soft plume (the silver one) .315 Lb/sec with a .060 jet vs. .320 lb/sec. It would be intresting to see what an A nozzle flows in this type of a test. The A nozzle is the largest internaly of all the NOS nozzles. Did you purge the system before each pull because that would effect the amount of nitrous used per run.

mrr23

purge was done before bottle was weighed to eliminate that factor.