FL vs FLH heads

[es225]

Can anybody tell the difference between panhead FL heads and FLH heads? Has it to do with porting and/or flowing? Both intake and exhaust? Was there a difference throughout the panhead production era (outside oilers!) or just in the first FLH years? Any pictures available? Can FL heads be converted to FLH heads?
Many question marks, many thanks for the answers...JW.

[Cotten]

To the best of my knowledge, only the spring pack spacing should be different for 61, F, and FL cams.

And I cannot find evidence that the Factory made even that distinction.

So just install your spring packs spaced appropriately for whatever cam you choose.

.....Cotten

[Ohio-Rider]

I believe the cam sets distinguished a FL from a FLH and the heads where the same. Right.....?? Not completely sure though.

[es225]

Part numbers of the bare heads differ, though: 16702-55 front FL, 16703-55 rear FL, 16708-55 front FLH, 16709-55 rear FLH. Prices differed also, and considerably: $62 FL, $102 FLH (49-56 spare parts book). So there must be something different between the FL and FLH heads indeed!
By the way, the Victory cam came in a year later, followed again one year later by the stiffer valve springs.

[Cotten]

I'm stumped.

...Cotten

[panz4ever]

Went loking through Palmers book, page 182..."starting in 55 there were two different sets of heads produced for each year OHV motor, a set for FL motors and a set for FLH motors. Other than the great price difference, the only real difference was the FLH head had a polished and flowed intake port for much better breathing..."

[fourthgear]

I didn't think that just the upgraded valve springs would make that much of a diff. in price so , there had to be some thing else done to the head assem. .

[Cotten]

The ports on my '65 FL appear identical to my '65FLH, for what that's worth.

....Cotten

[Panacea]

Cotten, do you think the FLH ports could have been polished originally? Forty years might hide that, Still hard to visualize HD doing any custom porting. Mike

[58flh]

All heads had to be cleaned-up of any casting boogers!--As far as polished ports ,the FLH seem to be a little more sand-mopped thats it!--The CCs are the same ,Flh heads had higher spring press. due to the V-or FLH cam. So basically all fl & flh heads are equal --the diff came in the 60s with the addition of outside oilers! Thats about it!-I believe there is an x-tra fin added in the 1960 for cooling -(I may be wrong on the year!) The fin really didnt do much anyway It was a good idea that didnt hurt anything or help eighter.--When I hold a gun to a extra finned head against a regular head = no diff. at operating temp. Test was done with st.60 in both bikes & Timing set equal (points!)---Comp. same both bikes stock running aq J cam!----RICHIE