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[panhead1]

Are 103+(17072-03B) heads any better than the regular 103 cvo heads?  found a cheap set and thought about switching them out.

[Unbalanced]

There is more a porter can do with the 103+ heads.   If you found them cheap I would jump on them.

[Doc 1]

Are 103+(17072-03B) heads any better than the regular 103 cvo heads?  found a cheap set and thought about switching them out.

The 103+ heads have a 30 degree squish which means you have to have the pistons to match the heads. Without the pistons the heads are worthless. I will say in my opinion the 103+ head and piston set was the BEST combo Harley ever had for making power....but....they quit making both the head and piston.
I have had the regular bath tub heads cut with a 20 degree combustion chamber and matching 20 degree pistons made from Axtell with VERY good results.
Doc

[panhead1]

Thanks guys. Wasn't sure on the squish. I knew the htcc ones needed to be matched didn't know these ones did also.  Guess I should maybe not get them if your not able to get pistons to work with them anymore. 

[Ironhorse]

So, if I understand correctly, the CVO 103 engine made up to 2007 is a totally different animal than the current crop of 103s found in the dressers and Ultra Limiteds of today.

[Fired00d]

So, if I understand correctly, the CVO 103 engine made up to 2007 is a totally different animal than the current crop of 103s found in the dressers and Ultra Limiteds of today.

That's the way I understand it (but I've been wrong/confused before ).

 
Ride Safe,
Fired00d
 

[Unbalanced]

Ironshorse that is correct.   They are nothing like the CVO motors so to speak as far as heads, cams, or throttlebodies that came on them.   Also as I understand it the cases are no longer cut the same way either.

I was told the cases used to be cut both sides at the same time giving the same bore, now I am told they cut each side independently.  

CVO 103 with Hemi Heads 1.900 / 1.625 valves   94/95 cc chambers
43mm throttlebodies with either 25 degree or 8 degree injectors dependent on year most were changed to 25 degree if they were 8 degree
cams were 253

Some things that are also notable are that they paired the older engines up with 5 speeds and different gearing compared to the new ones.    Many have concluded that the new motors / gearing have a much higher parasitic drag component to them. 

[Ironhorse]

Thanks Unbalanced. Another reason to keep my 06 CVO Ultra. I knew the new 103 didn't have the SE heads, but I  didn't know about the throttle body, injector angle, cams and engine case bore method. interesting info about the tranny as I have mine up at HD Dudes shop for a Baker 6 speed among other things.

Mark

[HD Street Performance]

I like them a lot when modified. They carry a 2.08 intake and 1.623 exhaust valve and will readily accept larger as long as V TO V is dealt with. I would have used them if I had a set when I built my 117. Instead I used the CVO 110 head a definite contender. The 30 squish band as cast becomes 20 easily and there are pistons available, plus when the bore gets bigger it becomes easier yet to get everything to work right. Similar to what we used to do with the HTCC CNC heads which were not too shabby either but once again had issues that needed to be dealt with.
All that said there's nothing wrong with the CVO 103 heads once again when modified. I recently did a set a guy put on a 120r that made 129/149 and hit 125 torque at 2100 carried that at 5k and was still pulling at redline, Tman 590 10.6:1.
A cam change would have culled the peak torque a little but the curve would still be flat and then I would expect another 10hp.

So I like them all I guess but they all take different treatment and valves to make them work to their potential. Some have inherent problems but none that are too hard to deal with.

[panhead1]

I have some wiesco 10.5-1 pistons in mine right now.  Not sure what heads i would want to be using.  If its better to work over my 103 heads or get the 103+ ones and make them work. Don't want to get crazy compression going since i ride the bike all the time.  I have woods tw5-6 cams in mine also. 

[Unbalanced]

I would give a call to one of the porters and ask their opinion of what they feel they could deliver from either and go from there.   In the end that is who is going to make this combination work.