Rotorhead87's Cosmo 13B-RE FC3S build-up

[sk8world]

If you are going for big numbers and want to flow air thru the plenum nicely you may want to have the RE upper mani cut open and grind out the plates that direct air off the TB. I will attach a pic for you.

[rotorhead87]

Originally Posted by sk8world

If you are going for big numbers and want to flow air thru the plenum nicely you may want to have the RE upper mani cut open and grind out the plates that direct air off the TB. I will attach a pic for you.

I didn't have the UIM cut directly like the picture you provided. I had section from each side and bottom of the UIM to allow access to the grinder to level out all the high spots inside of the manifold. The entire inside of the UIM and LIM manifold is smoothen for better air flow.