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Kpa range for VE maps?


cygnusx1

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I am building up some maps for my new MS-II. I plan on running 15-20psi boost. When I generate my tables, I can use the auto generate tool in Megatune.

 

I have dyno data for my motor at 15psi at the wheels. Should I enter that data for HP/TQ plus about 12% to get flywheel numbers? Or should I just guesstimate HP/TQ at 20psi so my table ends up with a 20psi range instead of just a 15psi range?

 

A bit confusing but if you've used the VE table generator in Megatune, this should make sense.

 

-Dave

 

PS I know the VE Table auto generator is just a rough baseline.

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I don't know if it has been upgraded, but it used to be that use of the table generator was strongly discouraged with boosted applications.

 

What I would do is put in one of the maps here (Moby's and others that have been posted), extrapolate the data to your desired kPa (usually boost level plus atmospheric and a buffer in kPa), then tune it with a wideband.

 

Mario

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OK so I will build tables that range from vacuum, 20kPa to boost 250kPa even though I will only use up to about 18psig.

 

250kPa = about 36psia (21.3psig)on the boost gauge

 

I guess I can borrow Big Phil's tables then.

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Dave,

 

250kPa = 36.26 psi, so if you are shooting for 18psi, I would set the upper most load band to be approximately 20psi to give you a little headroom. So adding 140kPa to 100kPa (atmosphereic pressure), will give you 240kPa.

 

Then I would start by making the lowest load band to be your idle pressure. My L28 turbo idles around 20in-hg which is around 67kPa. So set your lower load band to 60kPa or so.

 

Atmosphereic pressure is 100kPa, so make that somewhere in the midle of the load range. Then I would evenly space the load bands from 100 to 240, and then from 60 to 100. I put the load band up at 100kPa, and then went up and down from there.

 

When you get it started, and idling, set the lowest load band to match your idle pressure. Also, make the lowest RPM band your idle rpm. Then you can dial in a nice smooth idle.

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Well, I just spent a couple of hours making pretty maps. I am going to post a new thread showing my THEORETICAL maps. I dont have anything installed in the car yet. I am just practicing and building maps from looking at other maps and my intuition.

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