starting from scratch boosted 383

[V8hilux]

I wouldnt wait for cranking flooding before changing the cranking pulsewidths. If your injectors flow 4x what the stock items do multiply those those tables by 0.25.

yup, done that too.... didn't want to start hot till I 1/4rd em.

I'll swap the single fire thing too. good idea.

[V8hilux]

Is this right?

[antus]

Looks good

[V8hilux]

when do you blokes start with the voltage compensation and the injector pulse voltage maps?
what's the procedure to get it right with different injectors?

injector bias vs battery voltage
injector bias addon vs injector pulse width

would these ones have anything to do with things getting lean as the engine heatsoakes?

[antus]

Not likely to affect lean with heat soak. Add the data if you can find it for your injectors. Its not the kind of table that you can generate through logging, you need a proper lab style test bench. Defaults are useable, manufacturer specs are better.

[Holden202T]

this is what I use for deka 80's

injbias - deka 80.jpg

[VL400]

when do you blokes start with the voltage compensation and the injector pulse voltage maps?

This should be done as one of the very first things. If you get it wrong to start with it will just cause issues down the track.

It may also partly explain the lean idle if the table holden202t posted is wrong. This is the opening time (how long the injector takes to open before fuel is injected) and gets added to every inj event, so if you need 2ms of actual fuel and battery volts is say 12.8V the delivered PW will 0.93ms greater each time the injectors are opened. So, double fire gives two inj events per engine cycle and would be 2ms / 2 for delivered fuel plus opening for each, so 1.93ms and 1.93ms per engine cycle (total of 3.86ms per cycle). When switching to single fire mode it would be 2.93ms per cycle, 2ms plus opening time of 0.93ms.

As you can see if the opening time is wrong it will change how much actual fuel is injected, two openings of 1.93ms should be the same fuel delivered as a single 2.93ms if the opening time is setup correctly as per the injector specs - which can be hard to find!

[V8hilux]

AHHHHHHHHHH WIN !!!

I have just solved the 2 year long battle with LEAN HOT RESTART..... I was just doing a log to post up here to show you lot the lean hot start issue and I found the problem.

It would be 18+ afr on hot restart after a period of 10 minutes heat soaking with engine off. it would remain lean at idle UNTIL i put my foot on the accelarator just enough to get out of closed throttle idle mode which is approx 1000rpm, where the afr's would go back to normal.

take foot off throttle and it would go lean again....this would continue untill I got out on the highway and cruised at a hundred for a while.

It appears the voltage was dropping somehow after a heatsoak to the 11.8 range and I tweeked the "injector bias vs battery voltage" in the 11.2 -12.8 volt range and it went straight back to normal afr's.

Could this be the problem all along? maybe the alternator doesnt work real good at idle when it is heatsoaked?

I suppose I will find out if it is pig rich on a cold start. hmm. I'll cross my fingers.

It's all up and running Just need to do more work on the ve's. Waiting for the missus to get back from town wiith a couple more jerry cans of fuel....

Not sure on the spark maps? this gt42 gets 2bar boost at around 4,000 rpm and it's at 16 degrees in that column?

383needsvework.bin

[Holden202T]

you will have no end of issues with AFR's if the tables aren't right and you have charge issues. and yes charge issues after heat soak is all too common!

[antus]

Well there you go. I was thinking after I posted yesterday that the only way for heat soak to play a part there was if there were voltage issues caused by the heat and then you would see voltage drop in the logs. Good to hear the result!