Wolfgang (Mutant Motors by Wolf) is the one building the pipe. He calculates where they need to be based off of the exhaust gas velocity, gas temperature, and exhaust valve events. I think its a computer program, however he does change his step lengths around a little to suit the application. In my case, being a geared dyna, the pipe should favor the 3500+ rpm range.

 

Be interesting to see how well it does.

 

intake flow is very low,on our regular 124 street builds we`re seeing at least 325 out of our 2.100/110 heads (330+ on street/strip motors) also build many 2-1 burns collector pipes over the years.how are you measuring for equil length? we would fill the pipe with water & make sure they both hold the same amount,simpyt measuring them with string or a tape measure dosnt work

 

Steps were done by volume with water. the headers are not equal length, but tuned considering pressure losses through the bends on the rear head pipe. I do agree with the lowish flow rate on the intake, the flow was slightly compromised from the valves being sunk in the heads to accommodate the potential .276/.220 TDC lifts (might run a 1.725 on the intake).

 

Shouldn't hold back the big end at all! lol

 

No, it shouldn't and that's the important end. Especially in a race build anyway. HP wins races. Low end torque is for touring bikes to get their 900lb. bikes and 650lbs. of rider/passenger weight off the line. lol
Oops, did I say that out loud? ;p

Here's a 124" in a '93 XL. From the XL forums...
Here's the entire thread spanning 7 years.

 

I wouldn’t sweat the flow numbers. Wolfgang knows how to make power, set up proper pipe length steps based on motor needs, and I’m sure he also knows, flow numbers are just a tool to evaluate the heads, with VELOCITY being number uno. My street heads flow a bit north of 400 on the intake, but remember.....we are using street bikes on the -street-where a big, sewer pipe hogged out intake hole that flows huge numbers will be a dog driving around town at street compression, moderate, street friendly lift, and pump gas. Gotta have Big Time port speed. V Twins are basically a Pushrod V 8 sliced off, and for heads to Really make big time power, they have to match the motor, valve train, compression, fuel availability, cam profile, type and size of induction system, Exhaust, and how the motor will be used, combined with the honest goals of the owner/rider.......
Anything, anything, off even a little bit in the recipe, Equals less than optimum results. See it all the time, and the end result is a pissed off or disillusioned owner, who was guaranteed “big numbers”, and got far less at the end of the day than they were promised.
No free lunch.

A couple car quotes on making V 8 power......

https://rehermorrison.com/tech-talk-...nch-fallacies/

And,
Here is what Darin Morgan aka, HP king says...

”Cylinder head specialist Darin Morgan says that with all the aftermarket heads available choosing a cylinder head today is a difficult task. Unfortunately, a bad choice can cost thousands of dollars in wasted time, says Morgan, and a bad head choice may go unnoticed without ever lshowcasing how good your engine could have been.So with all the heads on the market, how do you make the right choice? Morgan says it’s a complex issue with no simple answer.

"I wish I could lay out some quick and easy mathematical equations or some simple guidelines to help, but there simply aren’t any," says Morgan. "It’s a complex issue, which is why so many people have trouble. The best way to grasp what’s most important is to use what I consider the five most important variables used to tune the induction system.

1. Average velocity;
2. Individual instantaneous velocities;
3. Shape/design (maximize a homogeneous velocity profile over the entire port and at the same time promote efficient flow);
4. Rate of velocity change; and
5. Airflow.

Morgan says that if you follow his five variables you’ll soon find the most important rules of designing an induction system are: Velocity, Velocity, Shape, Velocity and, finally, Airflow.”

 

I agree 100%. Far too often emphasis is put on flow and velocity takes a backseat when it should be the other way around.

 

Thanks for sharing that article, that was a good read. When I spoke to Wolf about the heads he told me just about the same exact thing as you. Most of his time was spent dialing in the port shape with the velocity probe, making sure the port had no dead spots. The heads were dialed in for what I wanted with longevity being considered as well.

I trust his recipe, as this same setup with his 110 heads, same cam, pipe, and compression made 163hp on his dyno (on 93 pump gas), and put his 700lb Road King in the deep 10s.

 

Anytime...👍👍
Ive only had Baisley and SA Racing touch my heads, but Wolfgang knows his stuff, for sure. You and Wolf have to be on the same page as to goals (Ex:longevity), to have a successful build at the end of the day. Remember, your numbers (whatever they end up being), with be compromised by those “street” goals, and a full drag strip 124” numbers will be different than yours. Just the way it is....At the end of the day, it’s why it’s so hard for example, for my Crap Cali pump gas 126” street bike to run high nines N/A-you have to thread a very fine line between street and strip. Take some away on lift, flow, velocity, intake size, compression etc.... go slower and watch the “big” numbers drop. Add comp, lift, fuel octane, etc...it sucks as a daily driver-but you’ll be a hero with your buddies- I’ve been at both sides of the coin and almost Ruined a very fast street bike cause I wanted “ more, more, more...”
So, pick your poison, and even if you do, you Still might not get what you want...but you might get what you need.