265 Hemi to efi

[heff0018]

The xdf file is ose$12P v112 1,2 and 3 bar.xdf and the adx file is ose $12Pv112 1 bar - delco$12p 2 bar petrol v1. hopefully this is correct, cheers

[heff0018]

I have copied across the VE and idle spark table from the straight 6 v111 tune and its made an improvement. Its not blowing any black smoke now, but still the o2 volts at idle are still around 850. I dropped the kinjflow value down but this didn't appear to change the 02 values significantly. What I did notice is how it affects the injector duty cycle value. What injector duty cycle value are we aiming for? cheers

[antus]

Duty cycle is a measure of how long your injectors are open for which depends on how much fuel your engine needs, how big your injectors are, and your fuel rail pressure. You generally dont want to go above 80% duty cycle at WOT, but other than that you dont tune by duty cycle.

Assuming you have a wideband connected and set up tune by watching the monitors and overlay Target AFR and Wideband AFR. Adjust your VE table to get Wideband AFR close to Target AFR. You may need to do a couple of cells at once, and then smooth the edges later.

You can also playback the logs and watch the history table "Calc VE table" in running average mode. Dont use this data directly as quick rpm/load changes, accel enrichment and decel enleanment all affect the numbers and if there are no enough samples in a cell its likely to be out. But if you drive smoothly and hold various load points for a while so you can collect more samples in that cell you can get an idea what range bits of your VE table need to be in. From there craft the VE table by hand and re-test. If the data comes out too all over the place dont trust it and dont use it as you wont make things better. You need to have confidence in your data.

[heff0018]

Thanks for the detailed reply. I am waiting on my replacement wideband contoller which should turn up next week so just trying to feel my way around tuner pro at the moment. I just wondered if monitoring different duty cycle values at idle could give an insight to the idle richness and plug fouling. I did give it a bit of a rev with the v111 VE and spark tables and it backfired, so it doesn't rev as nicely as the other tune. Is backfiring a result of too much timing advance or retardment, or can it be both? Cheers

[Dylan]

I tune by the monitor windows. I replied to a thread a whie go from wadond with some screen shots.
Everyone has there own methods. What the narrow band reading at idle?

[Jayme]

generally backfiring is from being lean more than timing. unless your timing is very extremely wrong. if its backfiring upon throttle stab, it could be lack of AE. you may need more AE with a custom manifold. generally the further injectors are from your valve, the more AE you need, as AE is to combat the fuel condensing into dropets on the walls upon sudden increase in manifold pressure. the more walls between the fuel and the cylinder, the more AE you need.

[heff0018]

I tune by the monitor windows. I replied to a thread a whie go from wadond with some screen shots.
Everyone has there own methods. What the narrow band reading at idle?

Thanks, around 850mv and it is not fouling plugs at idle with this tune. In fact after about 30 minutes idling the plug colour was just about perfect so I assume it's not leaning out either. I just need the wideband to arrive.

[heff0018]

generally backfiring is from being lean more than timing. unless your timing is very extremely wrong. if its backfiring upon throttle stab, it could be lack of AE. you may need more AE with a custom manifold. generally the further injectors are from your valve, the more AE you need, as AE is to combat the fuel condensing into dropets on the walls upon sudden increase in manifold pressure. the more walls between the fuel and the cylinder, the more AE you need.

Thanks, that's good to know.

[delcowizzid]

backfire out throttle too lean backfire out exhaust too rich.850mv idle is finegood starting point.

[heff0018]

Thanks, it backfired out of the throttle body. Just as an excercise I made up a new VE table that was an average of the V111 table and my original table that was running rich but had smoother acceleration. It ran pretty well but still had a flat spot about 1200 rpm and 30 kpa I used the cell tracing and changed the VE numbers to iron out the flat spot. I'm starting to get my head around tuner pro now.