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Ported Rb26 Head Required

tacker

By tacker,
in Engines & Forced Induction

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tacker Mentor

tacker

Posted
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Posted

well i can tell you just a clean out has to improve flow over the rough arsed factory job

Second attempt was done today 16 straight hours worth muttering dont f#$@ this one up, so off to have new valve guides inserted tomorrow.

Richieb Collaborator

Richieb

Posted
Posted

""""""love that cutaway pic.

there was some interesting info in last issue of race magazine about taking an internal cast of the port to see how smooth the shape is""""""

Exactly..!!, thats the way to get identical-ish ports.

Aaaaanyway Tacker, ya had the nuts to have a go, sometimes it goes wrong, but good one mate all the same, I been there too.

Cool idea the cut-away, nice one.

Lithium Grand Master

Lithium

Posted
Posted

Very nice pics, and bummer to see it went wrong first time - gotta gut you.

I was sure I've heard that unless you're going mental with it, theres no point doing any more than maybe a basic tidy up of the ports - no reprofiling or anything as they're so good stock. I know not everything you hear is true, but sure that I've heard that its not uncommon for RH9 cars to not have had any work done to the ports on the cars - just big cams and whatever is needed to fit them and actuate the valves correctly.

tacker Mentor

tacker

Posted
  • Author
Posted

not quite true there is a lot to do just to clean up the rough factory job, i found steps in the intake port just under the valve seat of over 1mm in depth.

Then it goes into inner radius for the intake and outer radius for the exhaust etc. There is quite a bit you can do on the intake to reprofile and enlarge the exhaust ports.

but if what has been done this time gives me a10 to 15% increase in flow i will be well chuffed.

pics tonight of finished head

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