PowerFC: Some DIY tuning comments please

[benl1981]

Changing the airflow tables - doesnt that affect the AFR or are they load points that are always in closed loop?

[justin911]

ben nah the airflow table lets you change the timing based on the airflow

[Dale FZ1]

Still unclear about the AFM correction. Won't this simultaneously affect the tables for fuel as well?

BTW there is possibly a slight driveability improvement with my adjustments listed from yesterday.

[paulr33]

as far as I know the airflow table affects ignition timing only. anyone clarify?

[justin911]

hmm so if you can change the ign using that method...

how would someone change the fuel levels quickly ???

I know theres the water correction.. but is that it ?

[bmxwrx]

You idiots!

Its called an airflow correction table because you are altering airflow values!

You are getting more knock by doing this because your car is running leaner and more prone to pinging.

If you wanna alter ignition, you have to alter the ignition table lol.

Edited October 19, 2005 by bmxwrx

[paulr33]

ok so the airflow correction table is airflow voltage vs inj amount then?

well im not seeing much more knock than i was last time, but what i am seeing is more timing thrown in, so how does that work?

[paulr33]

and wouldnt increasing the % values to higher mean more fuel, aka run richer not leaner?

[paulr33]

yeah he is right ive just realised its fuel correction table

oh well ill change mine back to what it was

so moving them up higher would have made it rich as all hell yeah ?

[justin911]

in the hacking a datalogit website though it talks about ign vs airflow,

ign vs battery power etc etc etc... ?

I dont think it talks anywhere about inj vs airflow..

also.. it would explain how sam "added some timing" to my pfc without having to change the ign maps.......

yeah he is right ive just realised its fuel correction table

oh well ill change mine back to what it was

so moving them up higher would have made it rich as all hell yeah ?

<{POST_SNAPBACK}>

[paulr33]

well looking at dataglogit (the app) it has a table for INJ airflow correction

but can't see any IGN airflow correction, so im not sure. The car felt better when i increased those values, and i saw more timiing on timing monitor so im kinda confused? but i guess it makes sense to be INJ correction instead.

can a powerfc guru confirm/deny ?

[Beer Baron]

airflow correction just bends the signal coming from the airflow meter to the ecu. so it affects both injectors and ign timing.

i don't want to be rude, but with the very thin grasp of tuning you have i wouldn't be touching your handcontroller.

[siksII]

i need a retune, and lately i have been driving around with ignition correction of 4-5degrees advance with next to nothing knock, including heavy load upto the redline. it seems like a lot and im not that game to keep advancing until i get it tuned.

Is there any risks other than knocking if i keep advancing it? And how much have you guys advanced the timing from a base map without knocking?

[paulr33]

nah thats fair enough ill just store my airflow correction values back to how they were and keep moving my ign tables up slowly. ive moved mine up a total of 10 deg with great results as far as driveability and response goes and also fuel economy has shifted to much more reasonable values, 400ks.

once i have datalogit (group buy) ill build a knock map and then tune the points that dont knock up

[paulr33]

by the way thats the point of this hole thread, to learn some self tuning that doesnt effect the cars reliability, sure if its dangerous / not safe then don't do it, im not say to do stuff thats not safe. to me it seems pointless to have complete engine management only to never manage it, to merely watch and assume its doing its best, soemtime the best tuning is done on the road in real time, you can't simulate everything, well at least in a practical environment anyway?

this thread is merely about learning and trying stuff, hence the DIY title

[benl1981]

The tuner where I'm getting my car done at on Saturday apparently mainly uses the airflow table to tune the car - he uses the FC datalogit. Apparently there are usually only a few ignition points he has to fix up but generally pretty good. He is the tuner that Sydney kid uses so I assume he is good

ill ask him if it would be ok to tune the light load areas (igntion) when driving and monitoring the knock

Edited October 20, 2005 by benl1981

[Robo's]

I think the only thing we cant tune is A/F ratios, it would be a nice to be able to rig up a system inside the cabin to have one eye on the A/F ratios and tune it on light , medium and full loads. As long as we have one eye on the "knock" and all ears on ping, a careful backyard tuner should be ok.

[bmxwrx]

Altering the afm values can put you in a different load site on the graph, thats the only way its going to affect timing. Best to set the afr to a nice value and adjust ignition from there.

[FLYGTR]

Paul , interesting thread and a good read but i have one question . I use a knock link on my track car and notice depending on what fuel i fill up with ( same brand BP ultimate) the knock link sometimes picks up a few knocks on different tanks . You might get "good" batches of fuel and "bad" batches and while adjusting your mixtures to suit every tank is fantastic you might be chasing your tail for most of the time.

adam

[Col-GTSX]

True... I have noticed difference inbetween tanks of fuel....