Have tried to seal lower intake 5 or 6 times in the last two months. Its always the same, engine running lean. So after replacing the gt-40 lower with another gt-40 am getting the same result. If I hook the lower intake gaskets into the tab on the head gasket there is only like 1/8 " (or less) of gasket material going above the top of the intake ports on the heads. If I adhere the gaskets higher without using the tabs on the head gaskets then there is not much gasket material below the bottom of the ports on the intake. I never had this issue with the dart heads but with these pro comp heads it is a problem. Im using the fel pro 1250s but I have used the stock gaskets for a gt-40 (explorer) with the same result. today my vac reading was 6 - 7" hg and the exhaust exiting the tailpipe was super hot and was getting lean codes.
Im starting to wonder if its the angle of the heads at the runners. I may try to loosen up the head studs and try to install the intake. I assume the headers would have to be unbolted and am wondering if (since the motor only ran for 20 minutes) after new head gaskets were installed, could I still use them after loosening and re torque. Also do they make a thicker lower intake gasket our motors ?
Im starting to wonder if its the angle of the heads at the runners. I may try to loosen up the head studs and try to install the intake. I assume the headers would have to be unbolted and am wondering if (since the motor only ran for 20 minutes) after new head gaskets were installed, could I still use them after loosening and re torque. Also do they make a thicker lower intake gasket our motors ?
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