Well, this forum seems to be a little slow lately, so let see if I can start a conversation.
Background: I have a 2014 GT500 with a stage 3 2.8L liquid-cooled KB kit. It has a catless H-pipe; exhaust is otherwise factory. I'm running 93 octane on a conservative 92 octane Lund tune. It's basically a garage queen street car; I don't put it on the strip. It has a factory crank pulley. The car runs great and is pretty fast; I think it would probably lay down a mid to high 10 with good driving.
My target boost pressure is 18 PSI. Based on all of the KB literature and forum posts I have researched, a 3.0" pulley on a setup like mine will get you there (or perhaps a pound or so higher). I originally had a 3.25" upper and the factory boost gauge would read a max of about 16 PSI...maybe an occasional 17 PSI on a cold night in optimal conditions. That was believable. I wanted to gain a consistent pound (or so) of boost, so I tried a 3.0" pulley. The factory gauge would read 20 PSI under full throttle. Ok, no big deal...naturally I didn't want to run that much boost on 93 octane, so I took the 3" off and moved to a 3.125" pulley. I didn't retune for the pulley swaps; KB techs said I shouldn't need to. The factory gauge still reads 20 PSI under full throttle. At this point, I don't believe it. It seemed accurate with the 3.25" pulley, but inaccurate with the 3.125" and/or 3.0" setup.
Reading through old posts here and on other forums, it is widely known that the factory gauge gives readings derived from the PCM and it isn't very accurate, especially after you start adding mods.
This isn't new information, but I'm just fishing for other people's experiences with the factory 13-14 boost gauge on modded applications...especially those with 2.8 KB kits or similar.
I'm planning to get a Roush vent pod with an Autometer mechanical boost gauge. I like the factory look. Thoughts on that setup?
Flaming welcomed; i'd like to spice the forum a little.
Background: I have a 2014 GT500 with a stage 3 2.8L liquid-cooled KB kit. It has a catless H-pipe; exhaust is otherwise factory. I'm running 93 octane on a conservative 92 octane Lund tune. It's basically a garage queen street car; I don't put it on the strip. It has a factory crank pulley. The car runs great and is pretty fast; I think it would probably lay down a mid to high 10 with good driving.
My target boost pressure is 18 PSI. Based on all of the KB literature and forum posts I have researched, a 3.0" pulley on a setup like mine will get you there (or perhaps a pound or so higher). I originally had a 3.25" upper and the factory boost gauge would read a max of about 16 PSI...maybe an occasional 17 PSI on a cold night in optimal conditions. That was believable. I wanted to gain a consistent pound (or so) of boost, so I tried a 3.0" pulley. The factory gauge would read 20 PSI under full throttle. Ok, no big deal...naturally I didn't want to run that much boost on 93 octane, so I took the 3" off and moved to a 3.125" pulley. I didn't retune for the pulley swaps; KB techs said I shouldn't need to. The factory gauge still reads 20 PSI under full throttle. At this point, I don't believe it. It seemed accurate with the 3.25" pulley, but inaccurate with the 3.125" and/or 3.0" setup.
Reading through old posts here and on other forums, it is widely known that the factory gauge gives readings derived from the PCM and it isn't very accurate, especially after you start adding mods.
This isn't new information, but I'm just fishing for other people's experiences with the factory 13-14 boost gauge on modded applications...especially those with 2.8 KB kits or similar.
I'm planning to get a Roush vent pod with an Autometer mechanical boost gauge. I like the factory look. Thoughts on that setup?
Flaming welcomed; i'd like to spice the forum a little.
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