i was wondering for a log manifold if it would hurt to have the same sizing id piping as the ports on the head flange or if i should go bigger

i thought if i had the same size throughout the manifold and then had my exhaust dp bigger that it would in turn help me to spool maybe a bit faster as its going from a high pressure area to one with little to no resistance

volumetric efficiency and such is something that im not too keen on so thats why im looking for outside opinions

thanks

1.5" sch10 or sch40 pipe is the norm for log manis. Thats about 1.6" I.D. and much larger than your ports. I weld the pipe in the center of the port and dremel the flange for as smooth as a transition as possible. Thats what most fabricators do. When it comes down to it a log manifold is a log manifold the design doesn't change much from application to application. There cheap reliable and easy so not much engineering goes into them. You want a better designed piece you need to step up to a header style manifold.



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yeah, for the time being im going to run the log style but i will be going to a header style after i get other things sorted out