Experts please: IFR and inHG Explained?
10-23-2005, 08:53 PM
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Experts please: IFR and inHG Explained? I'm tuning my newly boosted car (turbo). If I want to change the IFR under boost, which means 0 vacuum in the manifold (my stock MAP sensor is in place so it can't read about 0 vacuum), then what value on my IFR tablt do I modify: 0 inHG or 23.6 inHG?
I thought it was 0 inHG since this seemed like zero vacuum, but when I watch my EFI logs, the MAP sensor shows about 30inHG during boost. So the MAP sensore values represent the vacuum in reverse?
Thanks!
Tommy
I thought it was 0 inHG since this seemed like zero vacuum, but when I watch my EFI logs, the MAP sensor shows about 30inHG during boost. So the MAP sensore values represent the vacuum in reverse?
Thanks!
Tommy
10-23-2005, 10:55 PM
#2
you want to use 0 vacuum, MAP (manifold ABSOLUTE pressue) will read absolute pressue meaning wot=100 kpa which equals atm pressue. the vacuum table for IFR goes by manifold vacuum, once you are wot or under boost you see 0 vacuum. hope that clears it up for you and didnt confuse you more haha
