New Harley Motor
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
4-valve heads have been used in autos for many years and almost without exception to provide wide torque curves, from low rpm. It will be interesting to see dyno cuves from bone stock TC and M-8, to compare the two. I predict that once Scott and his team get their teeth into them the M-8s will soon outstrip TCs in all departments! 
HDF Community Team
Joined: Jun 2006
Posts: 12,776
Likes: 2,607
From: san antonio
Not what I am talking about; any HD cam will be an EPA cam. I am referring to a non-EPA cam.
HDF Community Team
Joined: Jun 2006
Posts: 12,776
Likes: 2,607
From: san antonio
4-valve heads have been used in autos for many years and almost without exception to provide wide torque curves, from low rpm. It will be interesting to see dyno cuves from bone stock TC and M-8, to compare the two. I predict that once Scott and his team get their teeth into them the M-8s will soon outstrip TCs in all departments!
Ultimate HDF Member
Joined: Jun 2009
Posts: 6,899
Likes: 3,412
From: OH
This is kinda what I was looking for in the thread that I started. I am interested to see what can be done with the new motor based on the changes. I am also curious about the tuner issues on the new models. Fuel moto says that they can get in with the PV but I have not heard if they have access to the AFR's if they can. That is the big thing that the updated harley tuners cannot change.
Road Warrior
Joined: Mar 2013
Posts: 1,923
Likes: 587
From: Alorton, Illinois
This is kinda what I was looking for in the thread that I started. I am interested to see what can be done with the new motor based on the changes. I am also curious about the tuner issues on the new models. Fuel moto says that they can get in with the PV but I have not heard if they have access to the AFR's if they can. That is the big thing that the updated harley tuners cannot change.
TTS already has a 17 and working on the calibrations. Won't be long. HD has already released the cals. This takes writing in the code to do, and only the tuning manufactures do this. They don't rely on third party to do this for them.
Stellar HDF Member
Joined: Nov 2012
Posts: 2,620
Likes: 1,091
From: Eastern IA
Hopefully when V&H , Fuel Moto and anyone else releases a new head pipe the output end size will fit most mufflers , as is nothing currently other than HD will fit it. Maybe even some adapters for the stock head pipe.
I'm sure the aftermarket is busy working on stuff for the new motor.
I'm sure the aftermarket is busy working on stuff for the new motor.
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Seasoned HDF Member
Joined: Dec 2005
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From: poway
Also the valve arrangement lends itself to better scavenging..