well, I just cant resist the temptation of gutting my bike,,,

I'm starting with a stage 1 96 A in a 2008 FXDF Fat Bob.

I picked up a new 110 kit for $599 27501-09, now i know its for the 09 touring bikes, I was planning on using the 110 heads and sending my 96 jugs in for boring,,, to 103 + o/s.010 and 11.1:1 SE pistons 21916-08A,,, with SE-257 Cams,,, Adjustable push rods,,, SE- super tuner.

here's what the big boz calc show for this build with dif head gaskets.

Head Gasket Thickness 0.030
Static Compression 11.53:1
Corrected Compression 10.21:1
201.4@ 2400 Feet Above Sea Level

OR

Head Gasket Thickness 0.045
Static Compression 11.1:1
Corrected Compression 9.83:1
193.1 @ 2400 Feet Above Sea Level

• SE 110 Heads 95cc
• SE 103 cyl o/s .10
• SE 21916-08 11.1 to 1 Compression pistons for 110 heads +20.3cc
  
• SE-257 cams corrected Compression 9.83:1 w/.045 <> 10.16:1 w/.030 head gasket.
• SE Perfect Fit OR adjustable Pushrods
• SE Super tuner

So here's were I could use input,, is 10.16:1 to much corrected compression, and if so should i go with a 0.040 or a 0.045?? I don't mind down shifting to pass, but I want to make sure the SE-257 has all it needs to maximize it.

 

We sign off at 9.6, 9.7 corrected here, and have for years.
I'll make mention, that is a WHOLE lotta' head, for that 103", and combined with that 257(that historically is VERY late power) you may not like the low-mid range delivery whatsoever.
Scott

 

yep, as Scott said the combo may be not optimized with that potpourri of parts.

I would stick with the OE heads and have them ported and use the proper sized parts.

I wouldnt run over 200 CCP on a bike that u want to ride alot. unless you lived in Denver or very high elevation.

 

Listen to Scott and mentor70; they are trying to keep you from making the classic mistake of putting together a set of components that will not produce the results you want.

I would even back off the 9.6 a bit and shoot for 9.3 corrected and between 180psi-190psi cranking compression. If it were my bike, I would have the stock heads ported and compression setup for the selected cam (after market not the SE257), bore for cast SE flat top pistons, TTS Mastertune and a suitable 2:1 exhaust. But, it's not my bike, so........................................

 

That's about the most miss matched setup I've seen on here. I would go stock heads ported, flat tops and something like a Wood TW 5-6 or TW7. A 30T pulley will also keep you from downshifting so much.

 

Cool,, so as far as compression goes, is 9.7 the limit to where starting problems start or just low RPM drive-ability?? As for the 110 heads on a 103, that's the stage IV kit configuration in the SE cat, except the Stage IV race kit uses the SE-10.5:1 pistons with a SE-260 giving a corrected compression of about 8.93:1 instead of the SE-11.1:1 piston / SE-257 combo with 9.83:1 w/.045 <> 10.16:1 w/.030 . Now I've heard Harley has a OEM 65 to 80 exhaust to intake ratio for EPA crap and that it should be more like 80 - 90 so I was thinking of a port and polish on the exhaust ports only sense the intakes are already vary large. ??????



Side note,, I drive at a elevated RPM already, generally 2 gear @ 25mph through our don't brink twice or you'll miss it town. And MOST of my driving is done on the hwy over 60mph being I live in the back woods of north east Washington with a 17 hwy mile drive to the nearest town from my house.. I'm in no way looking for Bubba's 2000-rpm torquer, I'd much rather have a 2500 cruiser and a 5000 rpm HOLY CRAP passing screamer.



SCREAMIN EAGLE® PRO STAGE I V KIT – 103 CUBIC INCH
Kit includes our high performance / high-flow Screamin’ Eagle®
Performance 110+ Heads which include large intake valves at 2.120" diameter
(our biggest ever), high-compression forged aluminum
10.5:1 pistons matched to the 110+ heads, an SE260 cam to
open the valves appropriately, allowing the right balance of
air and fuel to enter, Perfect-Fit Pushrods to accommodate
the higher cam lift, a 58mm E FI throttle body to get that air
flow to the heads, big 3-7/8" diameter highlighted cylinders,
then topping off this kit off with a “must have” Super T uner
to provide the right tuning capabilities. Kit includes gaskets.
For race application only.
27516-08B Black. $2,399.95

 

You have created a bit of a mess for yourself by buying parts before you planned the build. First, the parts you have don't play well together.

I would put the SE110 package on Ebay and start over. Bore your OEM cylinders to fit SE cast flat top pistons; send your stock heads out for porting and decking for compression to fit a particular cam. I happen to like the Andrews 48 and 54 cams or the TMan 525/555. Many here like the HQ or Woods cams but since my experience is limited to Andrews and TMan, that's the route I would take. Put her back together with a .030" Cometic head gasket, tune with TTS Mastertune if your tuner is familiar with that system; if not, tune with whatever your tuner likes to work with. V&H ProPipe, Thunderheader, Python 3 or D&D Fatcat are all good 2:1 exhaust systems; hard to beat the ProPipe for cost, performance and sound.

 

Not at all,, the parts were NEW dealer sell off's at under half MSRP.

110 kit $599 MSRP $1647
SE-257 $100 MSRP $299
SE-21916-08A $180 MSRP $319 .10 over 103 pistons designed specially for 110 heads.......
----------------------
cost: $879 MSRP $2265


I've always been the odd guy on the block,, so I'm trying to stay away from the cookie cutter flat top torquer setup "everyone else" has... I appreciate your input, after all i did asked for it,,,

The wright brothers would have never made it off the ground had they just listened to the common knowledge of thier day,,, better to try and fail, then to just step into a long line of 103 torquer's. Besides I'm doing all the work myself in my own shop,, so it's not like I'm stuck with it if I fail at making it a higher revving HP kick in the pants..



So,, what is the practical corrected compression range and why?
And what is the optimum Static compression for the SE-257?
And how large are the valves on a typical OEM ported head?
and if it's 2" why is that better then a factory 2.010" 110 head?
what is the typical CFM difference between a 110 head and a ported OEM head??

I've heard a lot of TALK,, but I have yet to hear any real answers i.e. #'s as to WHY a ported OEM head is better then a worked over factory big bore head.... which leads me to suspect some people of being mere sounding boards without any real knowledge as to why. As it is said talk is cheap,, so unless you KNOW WHY i.e. #'s please keep it to yourself,, not trying to be an a&% just trying to keep this tread from being high-jacked by those who only THINK what their told.

I truly love REAL advice from those who KNOW by experiences.

My dad always said,, "Next time don't think" i.e. KNOW!

 

http://www.harley-riders-guide.com/h...dson-cams.html Something worth reading. A 1.90 is the common intake valve for a street port, I left mine stock for now. I'm not going bigger until my crank is welded and balanced for the new pistons.

 

Those heads make great mid to upper rpm power , however with those cams you are pushing the emphasis even more to the upper rpm's but in a Fatbob and with 110" it will be less of an issue than in a tourer and 103". Did you cc those pistons to get those #'s? I'm also betting the pistons will be down in the hole, not at zero deck. I say put it together using what you have. I would keep it above 190 and below 200 and don't assume anything when you do the assembly, when assembling, measure deck height, measure squish, cc everything before hand, then make your adjustments to get the numbers you like and if it doesn't run the way you want you will have the info the make the correct changes rather than throw parts at it.