M8 CNC Ported Heads question
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Intermediate
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M8 CNC Ported Heads question
How does the CNC Ported heads compare to stock heads that may be ported later?
What I am wondering is, that if you were to do a Stage IV now, could those CNC Ported heads be used to good advantage later on a 124 or 128 build? Or would you want to work up your stock heads? I would be interested in a High TQ centric motor, mostly in by 5500rpm.
What I am wondering is, that if you were to do a Stage IV now, could those CNC Ported heads be used to good advantage later on a 124 or 128 build? Or would you want to work up your stock heads? I would be interested in a High TQ centric motor, mostly in by 5500rpm.
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How does the CNC Ported heads compare to stock heads that may be ported later?
What I am wondering is, that if you were to do a Stage IV now, could those CNC Ported heads be used to good advantage later on a 124 or 128 build? Or would you want to work up your stock heads? I would be interested in a High TQ centric motor, mostly in by 5500rpm.
What I am wondering is, that if you were to do a Stage IV now, could those CNC Ported heads be used to good advantage later on a 124 or 128 build? Or would you want to work up your stock heads? I would be interested in a High TQ centric motor, mostly in by 5500rpm.
The people I have worked with prefer the HD CNC heads to port from. They are a different casting and have smaller ports so they have more area to work with, at least that is what they say. The down side is they cost about $1200 to start with then off to the porter, so it's not cheap. The stock head works well as is and some of the builds using the stock head are within about 5% of the ported heads so you really need to ask yourself is it worth it for you?
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The people I have worked with prefer the HD CNC heads to port from. They are a different casting and have smaller ports so they have more area to work with, at least that is what they say. The down side is they cost about $1200 to start with then off to the porter, so it's not cheap. The stock head works well as is and some of the builds using the stock head are within about 5% of the ported heads so you really need to ask yourself is it worth it for you?
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Was hoping you might answer this, thanx! From reading a lot of threads that's what I had gathered. I had read that some porters weld up the stock heads so they can rework them smaller for velocity. Are the valves the same size? Sounds like CNC ported or stock would need "some" work.
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People can get confused on the M8 heads as some believe SE heads and CVO heads are the same thing. For the M8's only, All the OEM heads (2017 - 2019) are the same other than the CVO's gets a different paint color. The SE CNC's are offered in both colors and use the same valve sizes as the OEM heads but the castings are different. There are aftermarket valves of various sizes and lengths offered that fit all the heads.
So my reel question was if you had the CNC ported heads, would they suffice on a 128" Hi Dollar build. And it sound like they would need to be worked just like the stock heads.
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https://redirect.viglink.com/?format...a6af163c5.jpeg
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Road Master
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From: UK
There is a dyno chart in the M8 dyno section (Vision's bike I believe) which was a hi dollar 124 build that only made 125hp -- the concensus was that the SE heads held it back.
https://redirect.viglink.com/?format...a6af163c5.jpeg
https://redirect.viglink.com/?format...a6af163c5.jpeg
also SE valve springs have been breaking down the line, as fitted to HD CNC SE heads
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https://www.hdforums.com/forum/milwa...l#post18379251
As you can see the results are by no means bad at all, when you compare to the high dollar one's out there, here are the parts used in that build and as anyone can see there is nothing High Dollar about it, down to the stock CVO Air Cleaner!
Parts List
4.250" cylinders and 11:1 pistons
SE 64mm ThrottleBody
SE 5.5 Injectors
TTS Valve Springs
TTS 200 Camshaft
Fullsac MX pipe
Fullsac 2" muffler cores in CVO Mufflers