You might also try running the NOS using the Engine Coolant Temperature tables for a quicker response. Also if pulling timing has little to no effect, it's possible something else may be causing knock. (Like too much fuel)
You might also try running the NOS using the Engine Coolant Temperature tables for a quicker response. Also if pulling timing has little to no effect, it's possible something else may be causing knock. (Like too much fuel)
Man I am feeling really stupid. I don't understand any of what you guys are saying. Except that I know the guy who tuned my car for NOS also told me he was getting a ton of KR on the NOS. So it sounds like something that is common with these engines.
Bringing this back....
Have yall come to a conclusion yet?
I'm tuning on a 2015 LFX for a customer and the KR is hard to get rid of on the N2O. I'm currently down to -2 in some spots of the WOT section just to get 0 KR. I'm still playing with the overall tune trying to combat it and still have decent power. It seems to really like it around 10.0-10.3 and seems to pull less timing at that AFR but off the bottle it's a turd, which was expected, but its not even a tad bit of fun to drive around like that.
1999 Camaro SS #1601
1998 Z28 M6 cam/heads/bolt ons/9"
You tested actual fuel rail pressure? Fuel pressure on the fuel rail is after the high pressure fuel pump, which will be from 500psi to 2,200psi. You need to make sure that you are tapped into the fuel system before the high pressure fuel pump. And at that point, there would be not need of changing the values in the PCM for desired fuel pressure as it should only be in one mode when you activate the NOS, which would be High Flow mode. And just tune your NOS jets by that pressure commanded your High Flow mode table. Stock should be about 72.5 for High Flow.Originally Posted by CRTD
As for the Driver Demand tables, you can simply raise the 86-100% rows of the tables to allow for the engine to actually produce the extra power that you will be giving it with the NOS. The table simply tells the PCM this is the power that I should be making at this specific throttle position. For example: if you were to be adding a 100 shot of nitrous to the car, simply raise the 100% row 100.
The IAT spark table is factory set to all zeros. If you would like to end up using the IAT Spark table, simply enter the positive or negative numbers that you would like for the PCM to add/remove from the engine based on IAT vs Airmass. Once you have the table filled out like you would like it to be, then you need to go over to the Mult tables under IAT Spark and make sure they are allowing for the IAT Spark table to be enabled. Easiest way of enabling the table, would to just set the entire Mult table to 1.00. Also confirm that the Mult2, Mult3 and Mult4 tables are also set to 1.00.
Make your fueling is dialed in properly. 10.0-10.3 is way way to rich for a direct injection engine. Start off there, and if still having the issue. Post a log and someone should be able to help out.
I ran nitrous on my 2012 for the last 3.5 years and I found the best option was to make a timing retard box which I tied into my IAT. Being that I never see 10 degrees temps here I florida I pulled what ever timing I needed from that temp. Basically, whenever I arm my nitrous system it tells my computer that the IAT temps are 10 degrees and it pulls my preset timing. When not armed it ran normal timing. The timing box is simply a relay and a resistor and wiring...There is a thread how to make it on the LS forum..If you google making a timing retard box it should be listed.
Thanks for the reply Mark. Fueling was already dialed in by me on a previous tune. I started out rich to be safe. Will lean it out more when I get a chance to work on the car again.
The knock I was seeing I'm pretty sure is false knock. It's in the same spot every time. Had him take it to the exhaust shop to have the exhaust checked out and it was hitting against the heat shields so I'm almost certain that's the cause. I also added 30% to the knocks while tuning which didn't help either. Will probably get back on it this weekend and see if the exhaust fix was the cause of the KR I was seeing.
1999 Camaro SS #1601
1998 Z28 M6 cam/heads/bolt ons/9"
Hello. Yes I tested actual fuel supply pressure. Not the rail pressure. Thanks for pointing that out.
From what I remember about this car there was a significant delay that caused a very lean rise in AFR when activating the spray. Maybe because of the throttle controller opening so quickly? After hours of trying different things the only way to correct it was to stabilize the fuel supply pressure in the calibration and it worked. This car has been gone for a while. Customer has been doing other things. In fact, I have a full bottle of his and some other parts in the shop waiting for him right now.
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