Here is my run with 850psi bottle pressure and 62/24 jets. Window switch at 4000. I didn't have enough time to fine tune it but once I lean it out a little past 5k rpm it will pick up some power.
Nice numbers! Is it on a 125 shot? Why did you pick 4000rpm? Sorry for the questions, I'm new to nitrous.
I had 3 runs and was experimenting with the setup. I actually didnt realize I had it set that high. I have it at 3000 now but didnt get a run of that.
Nice numbers Chris, How do your a/f ratios look on dyno vs at the track ? A Dynojet only puts about a 3000# load your truck weighs about 5000#, you will prolly run leaner on the street or at the track. Also is 850psi what you run at ? With a higher bottle pressure you will again run leaner. Damn Dave has your tune fat, a 24 is a freaking small fuel jet for that shot. You have my dynos, how do we compare ? Definatley have the power for a 11 :dance4:
Strong power. A/F ratio is pretty good for 850psi. Were you able to log knock retard? I'm curious as to what kind of timing your engine would allow.
Let me try to answer all these questions. John, my AF is slightly leaner on the street. If you take a look at the in-car video I posted you can watch the AF at all rpms. I try to keep the bottle pressure high as possible 900+ but I had filled it just prior to dynoing and it was taking a while to heat up. Whats interesting is that Dave has my tune dialed in for low 12s off the juice and its right on at about 12.1-12.2. As soon as I juiced it the AF went way fat. Might be a difference in jetting between your Nitrous Outlet plate and my nozzle. Patrick, my KR is showing zero and sometimes it goes negative (for example -2.5) so I know I can throw some timing back at it once I have time to really get it fine tuned. If I remember correctly I was seeing about 18 degrees max timing.
I haven't talked to Dave about the timing. Honestly, I'm not sure the correct way to go about that? Would I just add a degree at a time until I start seeing some KR?
Yes, you want to add as much timing as you can without getting knock retard. I was just curious to know why you have a - value, your the only guy Ive ever read about with this problem. When you show - KR, is your spark on cylinder 1 higher than the base spark ? Example my truck runs 23-24 degrees Base and if I have 1-2KR, my cylinder #1 timing is 21/22-22-24.
You can see here the KR dips down to negative numbers then steps back up to zero. The cylinder 1 timing is between 16-18 with base spark around 16 all the way across.
Chris, sorry bro but that graph is hard for me to read and I use the actual gauges when I datalog not graphs. Can you answer this, when KR goes -X does your number 1 cylinder timing go up X or remain the same as base timing ? Example- On my vehicle if I have 23 degrees Base and 0 KR my #1 Cyl timing is 23, if I have 23 base and 1 degree KR my #1 Cyl timing is 22. How is your negative KR affecting your #1 Cyl timing vs Base ? Thanks.
Yeah I watch the gauges as well. The graph is the only way to show the whole run though. You can see when the KR is at -2.5 the base spark is ~16 and the actual is ~16.5. Once the KR starts going back up to zero the base and actual spark rise proportionately then when it shifts into third gear, the KR drops off a cliff to about -3.5 and base and actual spark fall as well. All three go up and down with each other. I dont understand it?
Check this out. This makes more sense. When the KR goes negative it means the base spark is higher than the actual spark.
