05 and 06 heads why ones better than the other

[hardyheadscom]

So why is the 06 and later  heads sooooooooo! much better than the 05 and earlier.
What`s your take on these heads...........then I`ll give ya mine.

[Jeffd]

In 100% stock form the 06 have bigger exhaust port and the floor is raised on the intake.  After they have been worked probably the same or close to it.

[mayor]

So why is the 06 and later heads sooooooooo! much better than the 05 and earlier.

I think that "soooo! much better" only applies to "as stock".  Meaning if no additional work is being done, then the -06 castings are better.  The stock -06 heads intake flow about 22cfm @28" more at .500" than the -99 castings, plus they include lighter valves and slightly better springs that can handle more lift. The exhaust flow more as well, but some might suggest too well.  Once a pro like your self gets a hold of either, then all bets are off.   

[hardyheadscom]

In 100% stock form the 06 have bigger exhaust port and the floor is raised on the intake.  After they have been worked probably the same or close to it.

\what does the raised floor do?/

[Jeffd]

well I am only guessing but I am guessing it helps with keeping the gas/air going in instead of getting pushed back out (reversion) increasing VE a bit by making an easier path into the combustion chamber.  just a WAG on my part tho.

[mayor]

if I mind correctly, most porters would prefer that the floor was not raised. 

here's some data on "as stock" TC head comparison:

truthfully, I don't think this particular author has a clue.   



edited to add new information from the -99 casting and -06 casting heads tested on the same bench.

[nc-renegade]

In 100% stock form the 06 have bigger exhaust port..... After they have been worked probably the same or close to it.

I think you hit this right on the head!  The exhaust on the 99-05 needs work to bring it to the same level of performance as the stock 06 and up.  Both are the same once you go to a stage 2 or up.  Not sure about the raised intake floor?

[fxstdavew]

Cause everyone on HTT says so

[Don D]

Hardy
What is your take? What is your opinion?

[harleytoprock]

My guess is that the raised intake floor improves the angle in which the gas enters the cylinder.  The direction does change from horizontal  to verticle. Maybe it also allows the gases not to favor just one side of the valve opening.

[harleywood]

Ummm, the raised floor increases port velocity and the larger exhaust lets it get out....How am I doing? 

[Jeffd]

if I mind correctly, most porters would prefer that the floor was not raised. 

here's some data on "as stock" TC head comparison:


truthfully, I don't think this particular author has a clue.   

Mayor, where did you find this?  I would like to read the rest of it.  thanks jeff

[maineultraclassic]

Check this comparison out -

http://bbhp.bigboyzheadporting.com/showthread.php?t=91

Steve

[hardyheadscom]

Check this comparison out -

http://bbhp.bigboyzheadporting.com/showthread.php?t=91

Steve

Yeh.............. big boys said it pretty good.

[mayor]

Mayor, where did you find this?  I would like to read the rest of it.  thanks jeff

I can check with the author, but I don't think it's ready for prime time yet.   

[Michrider]

Reading that link, doesn't make the 05's sound so bad?

If you were to work over some 05's should they converted to the larger valve stem?  Sounds like what they did to the valves and guides were to pick up a little flow and reduce weight.  Is this not a good thing?

[Jeffd]

So why is the 06 and later  heads sooooooooo! much better than the 05 and earlier.
What`s your take on these heads...........then I`ll give ya mine.

we are waiting LOL.  give us your take.

[hardyheadscom]

well I am only guessing but I am guessing it helps with keeping the gas/air going in instead of getting pushed back out (reversion) increasing VE a bit by making an easier path into the combustion chamber.  just a WAG on my part tho.

Very good.....the higher and rounder the floor as far a s HD heads go it picks up the air speed creating velocity thus VE. Velocity can be your enemy too. Air doesn`t like corners .Air can only hug a corner so long. then add fuel to the mix.Two things you can do.Radios the corner larger and angel back  or split the port  "wedge".  CFM will continue in the higher valve lift but will suffer in the low lift flows which can be ok depending how much flow you have at low lift flow .There is  a give and take with these 05 or 06 harley heads  . The 06 `s raised port isn`t a bad thing. it`s easier to take away than add in this case.The 06 head `s floor causes allot of velocity . With what most of us call stg 1 this works pretty well. To about .450 lift with what I do .Then the crooked  floor and lopsided port......... then add core shift "in  most of the heads " gives me fits with the stock valve seat. The 05 port is smaller and more consistant in the shape........still add in core shift.

The 05 ex port requires  a fare amount of time to prepare over the 06 but out come is the same.
If I had a choice I would want to start out with an 06....... less work on the exhaust. Intake seems to be the same time wise, outcome`s the same

[wfolarry]

Picks up the air speed where?

[POORBOY]

OK hardy your playing games again

[GoFast.....]

This is how much I thought of my 07 heads. I sold them on ebay to all the people who think their so great and bought me a 03 set for half the price to have them ported. The exhaust ports start out to big for shaping them sometimes as you would like.

[hardyheadscom]

OK hardy your playing games again

sorry had somebody come in to the shop.

[Admiral Akbar]

OK hardy your playing games again

sorry had somebody come in to the shop.

Max

[hardyheadscom]

Picks up the air speed where?

The air pics up speed over the hump of the floor ....Like an airplane wing......... the faster the air flows over the top "hump" of the wing it causes lift.
I get a great deal of  air movement by opening the mouth of the valve seat making the short side of the port steeper picking up air speed .


It`s time to go home I can`t remember if I Tboed OC Choppers or OC Housewifes tonight

[wfolarry]

"the faster the air flows over the top "hump" of the wing it causes lift."

And separation. The speed on the floor is already too fast. I don't try to make it faster. As a matter of fact after I re-shape the floor the speed on the roof increases. I must be doing something wrong. I even stay with the little stock valves in a lot of applications. 100/100 no problem.

And for all those guys that think the new heads are WAY better than the old ones I hate to be a heartbreaker but ask me who set a new world's record last year with those lousy '03 heads & that little stock throttle body on a little 95" bagger.
Bigger ain't always better.