Port Divider


Well-known member
Supporter 2018
I purchased a Clifford Port divider a while back when I bought my carb adapt in case I pick up a used or Oz header set. Going to have to hold off on the headers for awhile.

Is it worth installing with my stock exh manifold???

How much improvement/performance gain vs the effort????

This topic has been discussed a bunch, so if yo search you will find some extensive threads on this one. I think the general opinion was that yes this done help a correct the exhaust flow even with the stock manifold, so go ahead and do it. Although you will need to take the head of to get it installed properly.

Howdy Williboy:

The time to install a port divider is when you are upgrading your head or doing a valve job. You will need to deal with milling to compensate for the difference in head gasket thicknesses anyway. Since it is best to tack weld and/or pin it into place, the head must be off.

The port divider, by itself, on a stock log head, probably isn't worth than a couple of HP. But with headers and other head work it's function, of splitting the siamized 3rd and 4th exhaust ports and evening flow, is likely more significant.

I had one in my modified D7 head, before headers, and felt it was very worthwhile.

Adios, David
Thanks for the replies and sorry for my delay.
I remembered this being discussed prior, especially before last years crash, I couldn't find or remember the info.
I already had the head rebuilt ( new valves, guides, springs, hardened seats etc..) My mech/mach shop is good but doesn't know all the tricks, so the head was milled flat and the block was decked too, just not to compensate for gasket thickness. So I would rather not pull it off just to install the port divider.

Can I still do installed and use Moroso A/B epoxy???

Has any tried to install it in the car???

Also, what size is my chamber?? It is a C9DZ early '70s head