Just started running Nitrous and need to pull some timing out of my program. Haven't really messed with timing yet. So if I was to go to the extended spark timing tables (TunerCat) and go to say around 80 on my MAP values and wanted to pull 2 or 3 deg, would I subtract it out of that table or add it to the table? Reason I ask is because I was at the dyno and made a few runs on the NOS. I previously subtracted from the table before the runs. When I would look at my scan data, I noticed it was pulling timing in that area during the run (knock retard). Am I doing something wrong, or do I need to keep going more on the timing and pull more out. Any help would be appreciated. Thanks.

Ken R. 95Z

 

Yes, you want to subtract timing for "pulling". WOT area is 95/100 KPA, so that's where you want to change things mainly.

 

Madwolf, my WOT range was reading in the 80 to 90 kpa range and not above. I would guess because i'm up at 5200ft in altitude, or does that not matter. I would think it does. I got those numbers straight off my scans. Thats also the range where I was getting knock retard also. Don't really understand it though. I pulled 5 deg out in that area and when I nailed it on the dyno on the NOS, right when it hit the 80 kpa range, it read 7 to 9 deg of knock retard and then immediatly started coming down through out the run and ended up only retarding about a half of degree along the top end. Couldn't hear no pinging or knocking so I would imagine it was retarding timing enough, but do you have any take on this one? Wasn't A/F related cause I was running at about 12 to 13:1 and it did that weather I was on the bottle or not. It only started doing that after I pulled timing out of the table. Could I have done something wrong or not made other changes elsewhere that may need to be made when pulling timing? Thanks for the input.

Ken R. 95Z

 

You should use msd box, timing master or something else to pull it. Your not always sucking on that bottle..

imho.

 

Yeah, I know, but this is temporary until I get a new MSD.

 

What was the barometer (BAR)? What elevation are you at?

 

Inguneer,
I'm at 5200ft in Albuquerque. A nice power robbing altitude if I say so myself. If I remember right, I don't think I even run in the 90 to 100kpa range, so was wondering if I just need to make my changes in the range I run at. I'm assuming thats what I need to do. Going back to the dyno tomorrow and will play with it more then. Want to get my NA program maxed out and just pull enough timing out so it doesn't knock on the Nitrous. Runs good on the bottle, but on or off the bottle last time I was at the dyno and scanning my runs, I was getting 7 to 9deg of retard right when I nailed it at around 85kpa and after about 500 rpm, the retard started dropping like a rock down to 3 then 2 then 1 then below 1 by the time I hit the top end. Thats what i've been trying to figure out and what i'm also gonna try and get rid of at the dyno tomorrow. Have any suggestions I can try? Thanks for the interest. Its appreciated.

Ken R 95Z

 

By the way injuneer, the baro on the dyno was reading 24.91 and the temp in the shop was about 83.

Ken R.

 

Wow that not much pressure, I think the eye of a hurricane is around that. That could very well explain your 80-85 wot kpa. Just for comparison right now its 29.97 here in Big D. You could just replace your MAP sensor and check your throttle linkage but if thats what it reads I'd just increase my wot range to include 80-100 kpa.

 

Yeah quicksilver, it's low, but thats how it usually is. Altitude kills. I think I would probably gain 6 to 8 thents N/A and a bunch of HP just running it down there in Dallas. Are you talking checking my throttle to make sure it's opening 100%? I will, but i'm pretty sure it is. How about pulling the MAP and cleaning it out. Ever done that or hear of anyone doing that? I would imagine over time it could get dirty. Thanks...

Ken R 95Z