Quote:
Originally Posted by Nutbutt
Would love to know your theory on the rpm dip. Latest tune has been good with no stall but there is still a dip.
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I think it has to do with the PCV system. Last night I took the catch can line that went from the can to the intake tube pre-supercharger and branched it off with a 3/8th's line to the intake manifold. Since I didn't have a check valve I couldn't drive into boost range but when coming to a stop the RPM's didn't dip below 500 RPM's. I am ordering an E2 can with a single check valve to put on the dirty side while keeping the IPF can on the clean side for now to see if this works.
Right before the stall the IM pressure is -25 in/hg and the AFR goes to 10:1. On the OEM setup the IM vacuum would be pulling air from the air tube after the MAF, through the crankcase and into the intake manifold. The MAF would see this air travelling through the crankcase. With the IPF setup the IM vacuum is still there but it is not getting any air from that tube. The MAF is still seeing air moving though because of the supercharger spinning, so its trying to add fuel to burn off what it thinks is crankcase fumes but there is no air. When I branched the line last night it provided some air to help, but it is not the ideal setup since the IM vacuum was fighting the supercharger inlet vacuum and the air in the crankcase probably was not moving around much.
This is just a theory, I'll be testing it when I get the oil catch can. If it doesn't work at least I'll have a can that can capture all the oil that is by-passing the catch can now.
Quote:
Originally Posted by SIXJAK
Do you have the black ice insulator?
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Yes, I have the spacer installed but it stalls with or without the spacer.