Timing does not directly alter AFR in and of itself. However, by lengthening the burn time with added timing, you will lean out the fuel mixture. You will want to check the fueling after adjusting timing. You may not be in ideal timing now and there will be variables that you will want to verify with solid numbers. It will also depend on your octane and IATs how much timing you can safely add.
Thanks, I didnt know that it would be an easy answer for a guy who tunes cars. Well not really, I did. I just didnt want to bother him to do an adjustment, if it involved more than bumping up the timing. Thats why I wanted an answer first. He is 2,500 hundred miles away.
If he could have just revised my current tune file with 1 degree timing adj, well thats different vs needling actual drive data info to make other adjustments to go along with it.
Well, I guess the same thing that anybody is trying to accomplish when they up their timing. I can tell you that I'm not looking for worst performance. I'm also not looking to increase my knock or pinging. I had a local tuner back it off because when he was tuning it, he heard pinging. Come to find out when he was test driving it, I had a wire that was broke off from the map sensor. The broken wire was not apparent because it was right where it goes into the unit. So after I found this out , I repaired the map sensor wiring. Now it feels like the car needs to be advanced to where Pat g had it. It just feels a step behind when you accelerate. Flat, as if it's a little bit too retarded. The local tuner told me that he backed off the timing one to two degrees from where Pat g had it. I'm thinking I had the pinging because of the wire issue and that's why he backed it off. it's something I would prefer Pat g to do if it was just an adjustment of timing, versus taking it to the local guy.
Jova - Ha, Thanks, All has been good as far as car goes. I have had some problems solved by the board. Most of it was advise that was used to eliminate an issue vs solve an issue. Although the best help I ever got was from GOFEHRIT . You lent some good stuff as well.
So I will ask you . One degree bump need any other accompanying adjustments ? Or no big deal ?
All depends on how close your current calibration is from Knock. IMO, the ROI is not there. Without a log file, you have no idea how close you are. Could be way safe, or 1 degree from a cracked piston land.
I doubt any respectable calibrator would adjust without a log file. But, hey it's your call.
^^^^^ If any of the above post is referring to me, I'm afraid I'm no help at all. Heck! I'm not even allowed to change the mufflers on the aft end (let alone add some HP). You'll have to hopefully get the answers your looking for, from those in the know or make some small adjustments on your own. Then carefully analyze an verify if any worthwhile results happened. Sorry
-You asked if, when increasing timing, you need to adjust fuel or spark. "Timing" is the timing of the spark relative to the piston at a top dead center position, and one or two degrees of timing will not have any noticeable impact on your AFR.
-If you lost your MAP sensor from a broken wire and you're running combination SD/MAF fueling, it should fall back to MAF only and trigger a DTC. This shouldn't have caused pinging unless your MAF table is way, way off and you're running open loop, which could let you run extremely lean. For a daily driver, I would typically suggest running closed loop (I do it even with my mods).
-Backing timing off one or two degrees from a point where it's audible means you're still on borrowed time and likely have a ton of knock that you're just not hearing. 16 degrees of KR may not be audible, but will kill a ton of power. It may have already largely learned toward to the low octane table due to the knock levels, which could explain the flat feeling.
It sounds to me like it needs a proper retune. Good luck.
Thanks, that was a lot of helpful info. When I say I had a broken wire to the map sensor, I mean that was hanging on by a couple of threads and making contact and in the same 1 minute not making contact. The guy was doing the tune while this was occurring, unbeknownst to him or I. this is why I suspect that he retarded the timing compared to his last tune he did a couple of years back. I'm under the impression that since I am it about 4,300 feet above sea level, that it might be okay to up it up a couple of degrees. But I'm just going to leave it as is. Something weird happened, it might be something or might not be something. Car has been running pretty consistent lately. I had rotated the MAF so that the internal IAT sensor is moved further away from the coolant hose. Seems to be actually running good and consistent since then. Maybe I am helping the heat soak be alleviated by rotating it away from the hose. I don't think it matters if the actual filament is catching/measuring air volume by being in a vertical position or horizontal position. But who in the heck knows ! I sure don't.
One thing to note - the timing tables use a grid of RPM and cylinder airmass for mapping the base timing values. At a higher elevation, you just wouldn't end up hitting as high of a cylinder airmass, which is directly calculated from MAF and RPM at a given time, so it wouldn't end up calling the respective timing values. As such, the timing table wouldn't need to be adjusted to account for elevation specifically since the tables already inherently account for this by basing timing partly on mass airflow, which varies by elevation. Hopefully that makes sense.