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Down and dirty on it, Stock bottom end C5Z. Car is on E85 with a 100 shot wet.
Car has an outlet 102 plate on it, with NX 15300L Nitrous and 15200L Fuel solenoids. Outlet hard line kit, tweaked a bit to fit. Fuel line is still about a 1/3 less of the length of the Nitrous line from the solenoid to plate. Standard 3/16 lines,
Now, on motor the car runs the AFR (gas scale, stoich is still 14.68) at 12.5 across the board on the dyno, street the AEM sees 12.5-13.0 throughout the pull.
To combat the lean spike at the hit, I threw more fuel jet at it and I will have to double check what exact jet I put in, but I believe it is a 44F. Outlets charts calls for a 25F on a 100 shot with E85 and 55psi.... NX calls for a 35F on a 100 shot with E85.
I have a 6AN feed line to the solenoid. Nitrous pull, AFR starts at 12.7ish and dips down to around 11.2 at the top of each gear on the street.
Car runs great, I have 2 degrees pulled and plug shows its still pretty safe.
My first question is, which jet chart should I base my changes off of? And secondly, is this too much of an AFR dip. Obviously the jet charts are just a starting point and there will be fine tuning off that. I think I was too uptight about the lean spike and got too happy with the fuel jet. Figuring the Fuel jet is about 10 thou larger than NX suggests. What is everyone on E85 and nitrous looking at for a safe (SBE) WOT AFR?
My curiousity is why it isn't going that rich until later in the pull compared to just going rich right away. I do not feel there is any nitrous delivery issues, especially being on just a 100 pill.
A friend of mine just went through the same issue on a F body. He didn't have enough fuel supply to feed the injector rail and nitrous solenoid on the hit. It would go lean on the hit then richen up a full point. Some have used controllers to delay the Nitrous solenoid so the fuel sprays first. Some say screw it and use a dedicated fuel system up front in the engine bay.
Well, I know the lean spike is always a factor on fuel rail supply cars, nature of the beast really with that setup. I plan on changing the controller out this winter to a leash controller and commanding the fuel to hit just a hair sooner. I could do that now with the NOS mini that is in the car, but I don't feel like running more wiring for it at this time.
I guess since it has such as large fuel pill in it, is why I am seeing such a drastic fuel swing. I expect it to slightly richen up. I think I really just need to dial the fuel pill back and get it leaned back out.
I have a 150 tune wrote up for it, I may just put the 150 pill in and see where it is at from there, which I am betting it is going to be damn close on fuel at that point.
I wouldn't worry too much about what the jet chart says. It's just a starting point. Just follow your wideband and MPH and tune it from there. Also, you can shorten that lean spike further if you just wire channel 2 to your fuel solenoid. Go into the settings and make stage 2 match on everything. Only thing you will want to change is the activation RPM. You can give the fuel solenoid some lead time on the nitrous solenoid opening.
I wouldn't worry too much about what the jet chart says. It's just a starting point. Just follow your wideband and MPH and tune it from there. Also, you can shorten that lean spike further if you just wire channel 2 to your fuel solenoid. Go into the settings and make stage 2 match on everything. Only thing you will want to change is the activation RPM. You can give the fuel solenoid some lead time on the nitrous solenoid opening.
I wouldn't worry too much about what the jet chart says. It's just a starting point. Just follow your wideband and MPH and tune it from there. Also, you can shorten that lean spike further if you just wire channel 2 to your fuel solenoid. Go into the settings and make stage 2 match on everything. Only thing you will want to change is the activation RPM. You can give the fuel solenoid some lead time on the nitrous solenoid opening.
Brandon, do you have any idea why the car just progressively gets richer throughout the entire pull instead of it spiking and then being as rich as the fuel jet allows right away? Here is the dyno sheet with afr.. Red is on motor (afr is constant through the entire pull)..
So I chased a fuel issue that honestly wasn't there. Come to find that my wideband O2 once again is just junk. All things mechanical remained the same, slight fuel pressure drop, but not as much as the dyno showed. Car was reading a lot leaner than it was when on the dyno, and when the sensor was new in the exhaust. Sensor slowly read leaner and leaner over a weeks time. Went from reading high 12s to 13 flat at wide open, to low 13s, mid 13s, high 13s, 14.0, and then low 14s.
I was driving myself crazy trying to figure this out. I ended up replumbing my fuel lines up front to put the FPR after the fuel rail so the rail had a more constant supply.
Anyways.. I did a pull the other night, going over the setup again, 52N, 41F, E85 with 2° taken out from 28 total. This was the plug after a 3rd-4th pull, shutting the car off at 140 and coasting to a stop...
You can see where the cadmium was burnt off around the top ring, but the whole plug is too dark and wayyyy to rich.
Moving on to last night, replaced the 41F with a 35F and this was the result... Yielded rich still, but a better base to read the top ring. So I will be filling the bottles back up and pulling more fuel pill out of it. I feel that a low 30s fuel pill will get it to the 3/4 burnt ring. Plug temp looks good, timing strap is safe still it seems.
Yeah, you're right. It's still rich, but headed in the right direction. When you can pull the plug and it look that new, you aren't putting much heat in it. I'd shoot for a 50% turn of color and then you can lean it out further from there if the car likes it.
Yeah, you're right. It's still rich, but headed in the right direction. When you can pull the plug and it look that new, you aren't putting much heat in it. I'd shoot for a 50% turn of color and then you can lean it out further from there if the car likes it.
I planned on a 1/2 - 3/4 burn and leaving it there. Plug temp seems to be just fine as it is now. I won't change it out to a BR7EF until I put the 150 in it.
@brandon@nitrousoutlet i had the car back on the dyno this past weekend, a different dyno but did a baseline to make sure the car still picked up what it needed to. I've made a good bit of changes since this, but the basics are it's still an outlet 102 plate, nx 15200l and 15300l solenoids. 3/16 hardlines, 6an supply, outlet standalone with a brand new pump... Car still goes rich up top and I just can't get this figured out, I felt that maybe this was an electrical issue and possibly the nitrous solenoid wasn't able to stay open during the entire pull. I used output 2 on my N20 leash (changed controllers as well), grounded the solenoids with their own ground leads to the frame in the engine bay, made a hit but the car didn't feel like it sprayed (I feel the fact that I could only get the bottle to around 890 or so before opening it and it only had around 4 lbs left in it (10 lb bottle))..
So my thought was with just a single output lead powering the solenoids (previous nos mini setup was the same way), maybe that's too much for one 10g wire (even though at that length, a 10awg should be able to carry 30amps) with both solenoids. I'm just really questioning myself now.
There's got to be some reason why this thing wants to richen up like it does. It's not noticeable in first, second, or third since the pulls in each of those go so quick, but 4th is the long one, so around that 5300 range is where it starts to tank.
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E85 and Nitrous AFR 
