Head porting and Flow numbers ?????

[Don D]

All this microscopic examination is not needed.  A good porter knows what to do to get the result the customer wants. This is why I defer to R&R ET AL, they ported the heads from the original poster and know what to do to get the most out of them.

As for Gofast all he needs to do is send the heads and a check and they will be done right. No intervention needed, just supply the vitals and let the doctor do his work.

Hardest part is getting people to get real with what they want in the flurry of talk of big valves and ports, big cams, high compression, big throttle bodies etc. A non-tech can get confused fast. I know I talk to them all the time and most of them just want a big fat torque curve. The dyno numbers are an internet phenom / creation and when truth is brought out most just want a torquey fun reliable ride.

Many confuse torque with power and some very powerful bikes may even seem down on power to them by the criteria they judge by (roll-ons).

[Shadowdog]

All this microscopic examination is not needed.  A good porter knows what to do to get the result the customer wants. This is why I defer to R&R ET AL, they ported the heads from the original poster and know what to do to get the most out of them.

As for Gofast all he needs to do is send the heads and a check and they will be done right. No intervention needed, just supply the vitals and let the doctor do his work.

Hardest part is getting people to get real with what they want in the flurry of talk of big valves and ports, big cams, high compression, big throttle bodies etc. A non-tech can get confused fast. I know I talk to them all the time and most of them just want a big fat torque curve. The dyno numbers are an internet phenom / creation and when truth is brought out most just want a torquey fun reliable ride.

Many confuse torque with power and some very powerful bikes may even seem down on power to them by the criteria they judge by (roll-ons).

Hi Don,

Can you edit this and put it in bold face and larget type, LOL, maybe even red type.

Best to all,

Shadowdog.

[Sonny S.]

Don,

I'm getting the impression you are doing GoFast's heads.
My intention wasn't to put the person doing the heads on the spot.
I just wanted GoFast to give us the flow #'s he looks for when doing a specific build. you know, once the motor size, and cams are determined

[ejk_dyna]

<<Hardest part is getting people to get real with what they want in the flurry of talk of big valves and ports, big cams, high compression ...>>

...hey that's me...thats exactly what I want!!   

<<I know I talk to them all the time and most of them just want a big fat torque curve.>>

...and i want that too!!   

you can get it all but it is trickier and it is a lot more $$$

[Hillside Motorcycle]

 

[se]

if those R&R heads and i am not sayin they are not.. call them they will be able to tell you from the serial # on the head as to  what the cc are. 

[roadglide65]

RG65, I will give you an answer, but remember I do not speak for ALL CNC heads.

As a general rule:

Do they give flow numbers with the heads that they port??

The heads typically do not come with individual flow sheets for each and every head, but the nominal flow numbers are usually available, most times posted on a website or other printed advertising media.




are they cut from a model that was hand cut from the start?

AFAIK - unless they were knocked off from an existing set, the short answer is yes.

The CNC programs are written from a process called digitizing, this is a "point cloud" created from data points taken at certain specific precision measured intervals (typically .05" or less) from the original hand ported cylinder heads. Some of the basic geometric shapes do not require the digitizing, but due to the complexity of the port geometry it is required for the port surfaces..

That's the basics, I hope it is helpful.

PanHeadRed

Thank's for the reply.........  That's what I thought...........   

In the future Ill be careful how to word thing's not to  or cause any 

Again thank's

[GoFast.....]

I am reluctant to say a whole lot about what I am doing with the 107 until I get futher down the road with the project. Sometime this High performace thing can be quite humbling when Things do not turn out.

People are so diffrent. A lot of people are just I want low end Tq. I come from a long history of Harley riding and I am a part of a large family with a lot of Harley. Probably about 15 bikes. Two 110, one cov Vrod and one is my brother who raced in the 60s and 70s with his 95 with the bottle. We all ride together at Sturgis. For me its not about the dyno sheet. When I sold my 114 bad boy last year I thought I could ride a stock bike. Well it lasted until Sturgis and I did not like driving a stock bike when everyone gets on it and you feel like you are trying to keep up. Maybe this plays more into what people want then we think. Maybe no one just wants to talk about it. 

Don,
When I talked to you last year about the 98 build I was doing. I said I wanted a 98 That would hit 120. Everything you told me I needed to do was spot on. I went a diffrent direction because I wanted to try the WT26 but if I would have went with everything you told me to do it would have hit that mark easy. So guys want to get involved in the facts and others are like this is what I want help me and then there are guys that want to do it their way and to me its all good. The head porter is just trying to get people where they are going and it can get really interesting.

[torque4me]

this is way too deep for me... I had my heads flowed before build and compared to Branch "touring heads"...lol...at the top the branch out flowed my heads but all the way up and all the way down my heads out flowed the branch heads. Was told by builder my heads were...eh, ok? Numbers wont be great!

Hmmm bike rides really good, not hot, pulls hard everywhere... did great dyno numbers...beats up the guys I ride with...

the guy who ported the heads explained that you hit .100 lift on way up and way down, same with .200, .300 .400 but only hit .500 once so...max flow #'s in most street bikes mean nothing, its about velocity through the smallest hole....and when in the saddle i'd have to agree with him.

But...what does he know? He doesnt even port heads anymore...too busy being a daddy and chasing his wife around!


Merry Christmas everyone and Happy New Year!

[GoFast.....]

its about velocity through the smallest hole

That hole gets bigger the more cubic inches you add to it

[Hillside Motorcycle]

He's over on the CVO message board now.

[GoFast.....]

He's over on the CVO message board now.

hillside What is the biggest intake valve that you can run effectively in a stock head

[Hillside Motorcycle]

1.900" on the later stuff, but the seats used to be a little bigger.
In those cases, you could turn down a 1.940", to 1.915".
We pull the seats on our Stage III and up heads, and install seats that will accept up to a tick over a 2".

[ICANTD55]

I have a set of R&R stage 4 heads that I bought used and did not ask the guy if they supplied any flow sheets, Also e mailed R&R and have not heard back from them. 

I would call R&R again. If there used heads, then you may want to freshen them up before the install. R&R is very reasonable when the freshen up there own heads. At that time they should be able to acomadate all your questions. They may have been set up a certain way for a particular build. Talk to Art or Reggie Jr. JMHO