NVetro

So I am back from the dyno and had a few problems...i'm happy but a bit confused.

The car makes 441.92 rwhp / 420.16 rwtq N/A

We threw her up on a 150 shot using C16 fuel in the fuel cell....we used the NX recommended jetting and made it about 2 jets richer for saftey. For some odd reason we got a crazy amount of power out of a 150 jetting. Granted i have a nitrous specific cam, but it seems like its a little much...we had to lift off at 5400/5500 rpms because we thought something was wrong.

Looks like if we did the full pull it would have made 660-675 rwhp / 666 rwtq. Any thoughts guys? Does this mean with a 250 shot which I plan to run I will see 350 rwhp from that? It's a bit unexpected. Here is a comparison between N/A and out 150 shot pull, notice the red (nitrous pull) we lifted off at 5400-5500.

One thing I may be thinking is we had a problem with our micro switch activating the spark retarder..so we were running full timing with a 150 shot it would appear. If we retarded it 6 deg, would I make less or more?

Forgot to add, this is through a Nitorus Express wet kit w/ the MAF kit as the nozzle. It has a dedicated fuel cell with C16 in it running @ 45psi, 93 octane in the regular tank...our jetting was the NX recommended for a 150 shot...it was somewhere around 62 nitorus and 38 fuel.

What do you all think?

slowride94z

wow just wow

NVetro

I really wonder what she will put down on a 250 shot

1996camaroSSclone

I think thats an understatment

Z-RATED94

I think you may be right and need to check to see if the timing retard is working or not. Why no A/F line on the graph? Why make a pull if you can't check for A/F during the pull?
One last question, would you mind sharing the specs of the cam?

NVetro

Sorry we didn't print out the graph with A/F....it was about 12.2 and then it got a little richer to about 11.8 toward the end of the pull...so Idealy I would like 11.0-11.5 to be safe (11.0 prob)...so I am running a little lean....we will richen her up with a bigger fuel jet.

As for the timing retard, we definitly need to get that sorted out...I am confident with the 150 jetting we will see 675 rwhp / 666 rwtq i think.

As for the specs of the cam, its a bret bauer custom nitrous cam.... *Specs removed as per request* I forget the exact lift numbers I have to get it, but I told him I was planning on running nitrous only at the track. I was impressed with the N/A numbers with this cam and stock ported lt1 heads/stock ported intake.

Z-RATED94

I think on the nitrous pull it was just about done gaining HP when you let off. On my graph with a Nitro Daves plate kit it spiked very quickly to 468rw and was a flat line until they let off. The pull was done in mph (I hate that). They brought it up to 75mph (300rwhp) hit the gas and it gained 168rwhp by 80mph and was a flat line to 120mph.
On anothet day at the dyno we leaned it out a hair, 11/1. I was told it would be a little leaner at the track under load. At the track I put a little timing back in, and believe between the two adjustments picked up another 20 rwhp.
I only mentioned the track load to dyno load thing as I believe it's something worth considering. Your gain of 200rwhp is pretty cool, and I can't wait to hear about your track results. Thanks for the cam specs too, looks like Bret has come up with a cam that fits your needs. Now all you need is a 2nd stage (direct port) with another 150-200rwhp.

NVetro

Once I handle the the single stange ill add the 2nd stage. the bottom end can def. handle the 2nd stage. I plan to do it :-D Progressive controllers rock...on my dyno graph the n2o kicks in at 3000 rpms but only 45% because of my progressive controller, at about 4600 rpms she is at 100%. Ill report back with the 250 jetting once we fix the purge noid, its sticking open when you hit purge for some reason.

rskrause

There is very little difference between nitrous systems and the amount of HP/lb of N2O. You gain a bit with the right cam, but again not a huge amount. Basically, the only reasonable conclusion is that you injecting more nitrous than you thought. IOW, it wasn't a "150hp shot" it was a 200hp shot. What jets were you using and what was your bottle pressure?

Rich

NVetro

it was about 950 psi w/ bottle heater and the jets were: 62 nitorus and 38 fuel which are the recomended for a 150 shot...i went a little bigger with fuel for saftey.

rskrause

Well, according to the spreadsheet I use, a 0.062" jet at 950psi should be good for 175hp. You proved that, I guess. The car ought to fly, anyway.

NVetro

hmm odd....I'm almost 100% sure this jetting is the same for NX and the nitrous outlet kits. I got the numbers from Dave @ nitrous outlet.

Regardless its clearly not making a 150 shot worth of power hehe.....Hope she flys!

Ray@NitroDaves

the NX jetting is whp...the other was crank HP...a .062 is our standard jet for 150 rwhp