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Before Dyno

Posted: Fri Dec 22, 2017 6:15 am
by Cpur
Hi Guys,
Moving around in dtaswin, one finds quite alot of tables that alter the amount of fuel and timing.

I just wanted to know if there is a list of compensations that i must turn off before dyno mapping, obviously after running the engine to operating temperature.

Thanks and regards
And Happy Christmas and New Year to everyone.
Cpur

Re: Before Dyno

Posted: Fri Dec 22, 2017 6:23 am
by Alex DTA
The compensations must be on for mapping. They must also all be filled in correctly.
The ECU will calculate the compensation, and fill in the correct base value in the map.

Re: Before Dyno

Posted: Fri Dec 22, 2017 11:57 am
by Cpur
Hi Alex,
Thanks for the reply,

Example if the engine is at 80deg on the dyno. Should the 80deg be a 0 compensation on the coolant temp compensation. Then the cooler the water the more compensation? do you have an example table?

Thanks
Cpur

Re: Before Dyno

Posted: Fri Dec 22, 2017 12:51 pm
by Alex DTA
No. Fill in all the compensations correctly now.
Coolant is a bad example, as there's not really any reason to add compensations for coolant temperature.

For example, select the correct MAP sensor scaling in the scaling screen.
Go to MAP compensations (don't use the 20x14 compensations), and click the set to standard button for fuel compensations.
If you want to add some ignition compensations for high boost, do that now.

Repeat for any other sensors you want to compensate for.

Then map the car.

Re: Before Dyno

Posted: Thu Dec 28, 2017 1:42 pm
by Cpur
Hi Alex,

I cannot understand, sensor scaling is already done. Sensor Scaling is something totally different from Compensation? am i right?

Why is there not really any reason to add compensations for coolant temperature.

When the engine is at 40deg, it has to run on the main VE and compensate for the temp using the coolant temp compensation. Is this how it works, or i totally got it wrong?


Regards

Re: Before Dyno

Posted: Thu Dec 28, 2017 2:51 pm
by stevieturbo
All compensations need to be correct for each and every individual application...and that is entirely down to your tuner to decide what your engine needs, for your application.

Nobody else can tell you what you need for those.

Re: Before Dyno

Posted: Thu Dec 28, 2017 7:37 pm
by katana
stevieturbo wrote:All compensations need to be correct for each and every individual application...and that is entirely down to your tuner to decide what your engine needs, for your application.
Nobody else can tell you what you need for those.
Agreed but you need some baseline compensations to get the engine running without having to madly flounder around with the main map during warm up? IMO the actual compensation numbers should be varied only after the main maps are close to correct when up to working temps (when compensations should be minimal). It will take a few attempts from cold to dial them in - data logging in these situations is a great assistance. I'd guess some generic numbers from a similar style / size of engine would work (if sensors / resistances are similar) for baseline?

Re: Before Dyno

Posted: Fri Dec 29, 2017 12:15 am
by Cpur
Thanks. This was of great help. I found a map from extreme engines tuners. And compensations go to zero at 80deg coolant, and 20deg air. That should be the working range of the engine, mapped there, and then as Katana said enriched gradually depending on how cold the coolant is . Air goes leaner the hotter it gets .

Thanks guys. Regards
Cpur

Re: Before Dyno

Posted: Fri Dec 29, 2017 4:58 am
by Rob Stevens
If you read the manual it recommends using the 'start fueling map' page 31 and not the 'water temperature correction' page 18

For the 'air temperature correction' just press the 'set fuel compensation to standard' button. However on a NA engine this has caused me issues when the sensor is mounted in the air box due to heat soak.

Re: Before Dyno

Posted: Fri Dec 29, 2017 5:08 am
by Cpur
Hi Rob , yes it can be used for that the starting table. But what if the engine is run to heat up and then left idle and it cools down to say 50 deg, the starting map will not be used until another startup.
Thanks for your help.
Regarding the air temp comp, i used the default one , will see how it goes as mine is a turbo engine , never checked how hot the intake is but i think in summer with an ambient temp of 40deg i am pretty sure it will runn around 60.

Regards.
Cpur