Author Topic: Mapping cruise for best economy  (Read 24845 times)

Offline mattias

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Re: Mapping cruise for best economy
« Reply #15 on: October 28, 2010, 09:40:25 am »
The latter. When all tables are the same large size, that can feel good but when you're forced to use the same rows/columns you're screwed.

Offline AVP

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Re: Mapping cruise for best economy
« Reply #16 on: October 28, 2010, 05:14:33 pm »
i understand.

i made a lamda table that goes only up to 140kpa. its more workable. ill see how it is once the ecu arrives.

Offline AVP

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Re: Mapping cruise for best economy
« Reply #17 on: October 30, 2010, 06:18:13 pm »
ECU will be here on tuesday, only i wont, so i will have it next saturday.

I must say that the latest configuration regarding the cruise seems to be giving me the best results so far. So i have leaned out the 78kpa line from 1500-3500, and then gradually get the lamda back to 1.02-1.03 till 100-120kpa. That, so far has given me a decent little over 11l/100km in the city, which is ideal, since on the motorway it should be less. Also on 56kpa i take it to 1.05 and lower than that 1.07.

On the 1.1.81 firmware i will make sure the VE map is very accurate, so that the EGO works as minimally as possible, and i will make sure that the MAT vs TPS map compensates for heat soak and hotter inlet temps. That should also allow for less lost fuel during EGO adjustments.


Offline [email protected]

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Re: Mapping cruise for best economy
« Reply #18 on: October 30, 2010, 08:36:20 pm »
you should use the lambda table to set the target, then you can keep the EGO working normally throughout the entire table.
You'll find that the VE table will be fairly flat throughout.

Offline AVP

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Re: Mapping cruise for best economy
« Reply #19 on: October 30, 2010, 08:57:55 pm »
yes, the only  reason that i have on 1.1.27 the VE slightly on the rich side is to avoid having lean spots due to heat soak of the IAT sensor. Generally if my VE map is ideal and spot on, it works well until about 15-18C IAT and then EGO starts to add fuel instead of keeping zero or removing fuel. I found that on hot days, the car was struggling, because the EGO was not fast enough to add the necessary fuel, and therefore i was seeing quite lean spots until EGO kicked in. So after those few instances, i made the VE in a way that EGO always takes away fuel rather than add.

now with the MAT vs TPS table, i can keep VE ideal for the most occasions, and add more fuel on hot IATs etc.