Dan_Austin
Member
It might not be related to the head swap, as almost everything under the hood has been replaced, but I wanted to see if I screwed up and am on the right track.
During assembly my builder saw me modifying the Vortec plastic gaskets and asked why. I told him I thought the paper gaskets did not match the ports well and had an issue sealing. He suggested we test fit them, and they did appear to have good coverage and enough surface for a good seal.
Well, this morning I picked up the last we items needed before first start. The engine fired right up, but was pig rich. I had installed a set of 75lb injectors and had updated the tune to use them, but missed a step, and was using 3X more fuel than called for. Once I fixed that, it fired right up, but is 'idling' at 3500+. I pulled the intercooler and confirmed the throttle was closed. I then pulled the TB and checked the IAC, and it was fully closed in the key on/fully warmed up state. My last test was to tape a heavy peice of plastic over the TB, and it still is pulling enough air to idle at 3500.
So unless there is vacuum port I am over-looking, I am thinking I need to pull the top end and install the Vortec gaskets. Any thoughts?
Update-
I forgot to mention that the gaskets I did use were the Felpro 1203, without a smear of RTV. I also did install the SportsMachine vacuum like replacement kit with EGR delete. I confirmed all lines are connected and tight. I bought the manifold from a member here already modified and to my eye it was well done. I hope to be able to setup a manifold pressure/smoke test rig tomorrow...
During assembly my builder saw me modifying the Vortec plastic gaskets and asked why. I told him I thought the paper gaskets did not match the ports well and had an issue sealing. He suggested we test fit them, and they did appear to have good coverage and enough surface for a good seal.
Well, this morning I picked up the last we items needed before first start. The engine fired right up, but was pig rich. I had installed a set of 75lb injectors and had updated the tune to use them, but missed a step, and was using 3X more fuel than called for. Once I fixed that, it fired right up, but is 'idling' at 3500+. I pulled the intercooler and confirmed the throttle was closed. I then pulled the TB and checked the IAC, and it was fully closed in the key on/fully warmed up state. My last test was to tape a heavy peice of plastic over the TB, and it still is pulling enough air to idle at 3500.
So unless there is vacuum port I am over-looking, I am thinking I need to pull the top end and install the Vortec gaskets. Any thoughts?
Update-
I forgot to mention that the gaskets I did use were the Felpro 1203, without a smear of RTV. I also did install the SportsMachine vacuum like replacement kit with EGR delete. I confirmed all lines are connected and tight. I bought the manifold from a member here already modified and to my eye it was well done. I hope to be able to setup a manifold pressure/smoke test rig tomorrow...
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