Remind me again why you didn't want phenolic spacers at least in addition? Aluminum is an incredibly good heat conductor. So right now it'll help carry block heat into the IM, which undoes some good work from the IC. If you add even a thin phenolic spacer it should interrupt some of that heat xfer, right?
The main reason I'm not using phenolic spacers is due to the fact that they raise the fuel injector further away from the intake port of the head in Subarus. The main reason I switched plans from the long runner na intake to the short na runner intake was due to that fact. I'd at least 13-19 mm phenolic spacers on na intake to clear the avcs on the heads.

I do have some 3mm ones but most likely won't be using them since that's bumping up the intake manifold even further reducing hood clearance.

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I just put a preorder in for this pulley and will be our having the dampr attachment when Dom gets it manufactured. I guess I like to support the small business especially since my short block was one of the last ones he built and I pre-ordered his cylinder 4 coolant mod when it first came out.

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The KSTech aluminum spacers came in today. Good news is the Killer B turbo inlet now fits under the intake manifold and now I have to balls up and slot the intakes bolt holes so the manifold will line up to the spacers and tgv housings.

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Their port matched to the TGV housings and not the intake manifold. That's just how much meat Subaru leaves on the intake manifold and why companies like grimspeed use to port match intake manifolds to the TGV housings. I'm sure port matching the intake manifold is minimal gains but I'll be doing it since I have the tools and abilities to do so. The sti intake manifold has about the same lip as well.

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