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'06 and later cylinder heads


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Looking for knowledeable opinions on cylinder head improvements in '06 and later TC heads. From what I understand, stock heads in '06 have improved ports or flow in addition to the new style barrel valve spring. Anyone have any experience or good info??
the later heads are much better than the earlier ones but there's still room for improvement with a quality port job. Flow is everything but you need other upgrades to get the most out if it.
The '06 Dyna head has a different exhaust port.In '07 the entire Big Twin line has that head.The intake needs a little work in the valve bowl around the guide boss and some on the short side.The exhaust needs a good bit of work but it is very easy to go too big and lose flow at lower lift.Biggest problem with the exhaust is the bulge from the head bolt passage that occludes the pushrod side of the port.
The beehive valve spring is nice but if you go to a higher lift cam you'll need springs to accommodate the lift.How much cam and compression are you looking at?Honestly you should start with a cam and design to that.There's a nice cam or two that take advantage of the stock stuff.