Different AFRs at the same load point and RPM

Tuning The Delco In Realtime
Posts: 3075
Joined: Mon Aug 02, 2010 6:35 pm

Re: Different AFRs at the same load point and RPM

Postby Dylan » Mon Sep 10, 2018 9:43 am

9c1vs wrote:
Dylan wrote:Hi mate, only from viewing the screen shot.
The first red circle is under acceleration and AE will be in effect.
The second one is more steady state. They would also be in different MAP readings which play's a huge part in VE.

Given the different intake the manifold fuel part of the acceleration enrichment calculation would need altering.
That can help with the delay with AE taking effect.

Also with the different intake the coolant contribution table will need some work along with the charge temp table to help stabilise the actual AFR.

I'll have a run of the log tomorrow night.

Hi Dylan, they both run through the 90kpa area i have highlighted by the red square, it will show up on the log. You gave me a hand with this tune a couple of years ago which i really appreciate. I got it to a point where it drives pretty well and lost time and interest to keep working on the tune. But I am motivated to have a play around with it again and do some work at tidying things up again now!

When I view the log it will tell more, but in that screen shot your have hi lighted the 90kpa but the bubble trace isn't in those cells on the VE table

Posts: 79
Joined: Sun Sep 29, 2013 10:33 pm

Re: Different AFRs at the same load point and RPM

Postby 9c1vs » Mon Sep 10, 2018 10:02 pm

I had a look at the coolant contribution and inverse air temp tables. I have fiddled around with them a lot when i was experimenting on this tune a couple of years back but i lost interest at the time.

If it is the air temp offsets that are causing the variation, which condition is more likely to be correct? The readings when the trace transits across cells or when the trace holds steady?

From what i can gather, the offsets are usually used to correct conditions when te actual air temp is lower than the MAT reading due to heat soak? However, does the opposite ever happen? Ie: the MAT sensor reading is lower than the actual air temp?


Return to Realtime Delco Tuning

Who is online

Users browsing this forum: No registered users and 2 guests