Well-Known Member
I came across a new hemco 66mm and was wondering if it was better than the KB or AF plenum.
The reason I ask is that after many searches I haven't come up with any meaningful comparisons between them.

Aside from swapping them and testing the differences myself I was wondering if anyone has already compared the two designs and noted the differences if any at 28 lbs. of boost and higher.

There are plenty of threads out there but they generally create more confusion than solid answers. I run a 70mm KB right now and it seems to distribute the air fairly well as the plugs are all close when I check them.

I would test myself but don't want to open up the hemco to 70mm just to test and see that it wasn't worth better distribution of air .
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Well-Known Member
Yes, see post #19 the third one tested... "similar to the accufab"

If I read that right, the hemco is a little better.

The only difference in my setup is I run a KB/1" spacer and it seems to work real well.

I wish they would go back and do these tests again with a spacer as it changes things a bit and I would like to see the results.