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Reply to "A(nother) Bridge Too Far"

Once the guides were gone and the valves were out of the way, I was powerless in the face of temptation and succumbed (again) to the "while we're in there" syndrome.

As such, I had Jason (VintageVolks) do a "fluff-n-buff" (insert sophomoric joke here, Jethro) port clean-up. Panchitos come with very well designed "as cast" ports-- they're meant to be ready to go without any porting. Indeed, there's almost no extra material in the casting to remove if a guy DID want to port them, and what makes them so magical is that they flow ridiculously well with a very small port. This is what the "as cast" ports look like:

Panchitos, Raw Ports

There's really nothing to be gained by messing with the ports, but the theme here is "why leave well enough alone?", so we (I) wanted to just remove the casting flash-- no reshaping or enlarging of the port walls, but just a clean and deburr.

Before anybody says anything-- yes, I know the intake needs some surface character to keep the mixture in suspension, but taking it to this level should have no negative ramification. I was going to have VintageVolks put a mirror finish on the chambers and exhaust ports (not for flow, but so that carbon doesn't stick as readily), but stopped the process before it got out of hand (see @Panhandle Bob-- I can stop any time I want to!).

This is what we've got with a bit of 80 and 120 grit and a die grinder:

Panchitos, 120 Grit

We're nowhere near done yet. The new guides will be installed (the heads heated and the guides chilled-- Jason shoots for a 400* temperature delta) and cut for the seals.The heads will be flycut to 56 cc chambers to get 9.9:1 CR with .040 copper head gaskets (assuming 0 deck). If this proves to be too much, I can get back to 9.4:1 by swapping the .040 gaskets with .060 gaskets.

Once the chambers CC correctly, Jason will do a nice 3-angle valve job, and we can turn our attention to the beehive set-up, and the Hoover modifications to the rocker arms.

Stay tuned for the next exciting episode...

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Images (2)
  • Panchitos, 120 Grit
  • Panchitos, Raw Ports
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