AFR/Timing/Fueling question
 

Hey guys, I want to start focusing on fixing my fuel map (it's pretty ugly right now) and was hoping folks could look at my AFR target and Timing maps so I know they're right before I start adjusting fueling. From what I'm hearing on fueling it should be going up in a linear fashion, however I don't want to play with the fuel map until I'm sure everything else is OK. I attached my fuel map for kicks if anyone wants to advise me on this. I'd like to avoid going to a Dyno this time, I'm tired of paying for peak power and having shitty cruising fuel economy.

So, there's no VEA or VEAL for a Hydra? :giggle:

Your AFR table doesn't make sense to me. Some areas have sensible values like 12:1 and 14:1. Other areas have gibberish like 0.5:1 and 43:1. What's up with that?

Do a search for AFR tables. There are threads with good examples along with discussion of why you use certain AFR's in certain operating areas.

Oh shoot yeah the AFR table and Timing table CSVs are backwards (AFR table is the timing table, and vice versa). I tried using interpolation to clean up my fuel map, but it gutted some sections so deeply that they would likely have very lean cells.

Bump. Anyone?

I don't run that lean at idle, but run leaner in cruise(15.5-16), and I think you can run leaner in your under 8 psi boosted cells(~12.2-12.7). I didn't look at anything else yet because I'm driving.

I have trouble idling smoothly at 900rpm and anything more than ~14.7, but anything 1250+ and in a vacuum cell was adjusted leaner (target of 15.6, might bump it up even more), as was boost up to 6psi (target of 12.2:1, 7psi has 12:1 and 8 has 11.8:1).

Car runs surprisingly well in cruise for running so lean, just need to go through a tank without any ignition issues and I should have some improved economy. My last mostly freeway tank I got 22mpg, if I can get 24 I'll be happy. If I break 26 (doubtful) I'll be back to the worst mpg tank I had prior to converting to turbo.

Some of the economy might be from your timing too. Joe has a good thread where he adjusted his timing in the cruising cells for fuel efficiency. Basically, the closer you are to MBT the better economy you will get (which makes sense, a more complete burn, more torque).

IIRC he was datalogging pulsewidth to help him determine if a change resulted in better or worse economy.