Low fuel pressure....
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Joined: Dec 2025
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Low fuel pressure.... Hi guys,I am new to tuning(very mutch so) and wanted to ask,patg is tuning my car atm and he says I have low fuel pressure that's why I am seeing very lean afr at 5000plus rpm,this was strange to me because I have a kpm duel intake fuel pump rated for 1000hp(car maybe makes 650whp with pump gass and methanol injection) and I have whipple fuel rails,after some research I found this line of text in the kpm instructions which explains alot but also seems very dumb,it reads.THIS SYSTEM IS DESIGNED TO LOWER FUEL PRESSURE UNDER ENGINE LOAD TO INCREASE FUEL DEMAND. I was like whattttt.then u read something about why it does that and it has to be tuned with longer injector pulse width to make up for the lower fuel pressure and this result in more stable afr,is this something that works or just stupid?,I can almost not believe the fuel pump lowers pressure when engine load goes higher.
