Atwood Performance VTF sponsor

[A Atwood]

Welcome all. Interested in a set of great flowing cylinder heads for a reasonable price. Check out my website and let me know if I can be of help. I will be offering custom cams that will be matched with my cylinder heads soon as well. ARN

[wkohn]

Originally Posted by A Atwood

Welcome all. Interested in a set of great flowing cylinder heads for a reasonable price. Check out my website and let me know if I can be of help. I will be offering custom cams that will be matched with my cylinder heads soon as well. ARN

The work on your porting looks great. Like the details you go into on your web site.

[Totenkopf]

ARN,
How did you become a Harley head porting specialist? What is your background?

[FXDRYDR]

Originally Posted by A Atwood

Welcome all. Interested in a set of great flowing cylinder heads for a reasonable price. Check out my website and let me know if I can be of help. I will be offering custom cams that will be matched with my cylinder heads soon as well. ARN

Welcome!!!

[A Atwood]

I became an instant performance enthusiast when my older brother bought a camaro when I was 15(1985), and began doing performance modifications to the 350 engine. I used to go to the track with him and ride in the car. What a thrill. My first performance car was an 83 Mustang gt. I read every article I could get my hands on and soon realized that cylinder heads were the key foundation to making power. Shortly after, I bought one of the first set of Dart heads offered for the small block Ford. I couldn't believe the difference it made at the track and the seat of the pants feel. I was grinding on heads when I was 20 and I have done it on and off since then, but always for myself and without a flowbench. I have always done all my wrenching myself and have put together many different performance engines. I am currently working on a 408" sbf that should put out near 600 hp and run on pump gas on the street. I am all about streetability.
I have always loved Harley Davidsons but never got one until a couple years ago. I would probably have had one years ago but a divorce in 97-98 set me back quite a bit. I'm sure a few of you can relate. Anyway, as soon as I got my bike, I was instantly looking into performance upgrades. So I began looking at cylinder head modifications to Harley heads. I have always been intrigued by cylinder heads, so I felt it was time to take this passion of working on cylinder heads to the next level. I began assembling tools and working on some heads off e-bay for some practice. I bought a superflow sf600 last year and began flow testing and experimenting. I made the call to Joe Mondello late last year and spoke to him on the phone and was impressed. Joe Mondello has ported more cylinder heads than any other man on earth. He told me he could teach me all the techniques that it has taken him 50 years to learn and bypass all the mistakes that self taught porters make. So off to Tennessee I went. That man was the pickiest person I have ever dealt with, but that is why his work is so perfect. He has ported everything from lawn mowers to top fuel dragsters. I have nothing but the highest level of respect for Joe Mondello. He teaches advanced Harley porting techniques, and Harley Davidson themselves have worked with him on heads. He taught me the proper way to port a Harley head and told me to keep practicing until I get it perfect. Joe worked with me the entire time I was down there. When he has students, he stays in the porting room and works with you one on one . My goal was to always become a VTF sponsor, but not until my techniques were perfected. I love experimenting, so going back and forth from the grinder to the flowbench is always interesting to me. I am an absolute formula and calculation junki. I have many different formulas that I use to help combine the proper combination of components. I am all about volumetric efficiency and high flowing cylinder heads. My stage I heads flow over 250 cfm on the intake and over 200 cfm on the exhaust. This at 399.00 is, in my opinion, an absolute performance bargain. When I move up to a 1.900" intake valve(which I always reccomend if the pistons have the clearence for it), my intake flow goes up to 265+ cfm and does it with the stock intake port opening. Now I know many of you guys talk a lot about velocity and for good reason. The formula for inertia is mass X velocity squared. When measured at the center of the port opening, my 1.900 intake flow over 30% higher velocity than the stock 99 casting and 25% higher than the 06 casting. This is because the cross section hasn't changed at the port opening, and there is a direct proportion of velocity with flow increase. I always remove the least amount of metal I can to get the results I want.
I began selling some heads on e-bay and was impressed with the response. I did many sets of heads from guys who read my auction advertisements and sent me theirs to be worked. Well I knew I would wait to become a VTF sponsor until I had it down to a science. I am now 100% fully confident in my products and I am sure their performance will speak for themselves over time. As Joe put it, "these heads are bitch'n!"
I do not plan to be a high volume cylinder head porter. I work one set at a time and spend a great deal of time with each pair. They do not leave my shop without meeting my exact standards. Joe taught me to be extremely picky and take great pride in my work, and I do. I am very excited and enthusiastic about all this and look forward to working with many of you. This is a great forum. In the future, I plan to take my business to an even greater level, but I don't think I should get into all that just yet. ARN

[Totenkopf]

Thanks! that is exactly what I was wondering about. Sounds like you had a great mentor. Some guys learn from years of experimenting, or looking at other heads, racing at the track and seeing what works and learning why. And then having the foresight to figure out how to back that into a street motor. Crunching numbers and matching key parameters is essential to getting a great working motor. The porter needs to know the cams available and what the builder is doing with the rest of the motor and what mission is meant for.

[swmnkdinthervr]

Originally Posted by Totenkopf

Thanks! that is exactly what I was wondering about. Sounds like you had a great mentor. Some guys learn from years of experimenting, or looking at other heads, racing at the track and seeing what works and learning why. And then having the foresight to figure out how to back that into a street motor. Crunching numbers and matching key parameters is essential to getting a great working motor. The porter needs to know the cams available and what the builder is doing with the rest of the motor and what mission is meant for.

Yeah...in lay terms...cool...

[wkohn]

I knew all that and that is why Arn is going to get my heads when I come up with the money.

[rodriguc]

Great website and bio...good luck on the VTF and thanks for being one of our sponsors.

[sledman]

When do you think you will have some dyno sheets/info on your website?

[A Atwood]

Can't say exactly when. I have made requests to each pair that I have done to send a copy of the dyno sheet to me. I hope to see some coming back soon. I am also going to do some dyno testing myself and will post as soon as I get them in. I know everyone on this forum, including myself, loves dyno results to compare combinations and components. ARN

[A Atwood]

There aren't many flow #'s on my website yet, so I thought some of you might like to see some. The two examples given are the most recent of each type that I did.
All tests were conducted the same way. Intake ports tested with 3/4" radius on inlet. Exhausts tested with 1 3/4" X 6" flow tube.
Tests are conducted @ 28" depression on SuperFlow SF600.

Test example #1 is a stage I port(new stock size valves)with 1.845" intake, 1.570" exhaust on a '99 casting.
---------Intake----------Exhaust
------stock---ported---stock---ported
.100---65------68-------46--------56
.200--125-----133------102------116
.300--173-----191------142------163
.400--190-----231------160------187
.500--193-----247------168------199
.600--193-----251------170------205


Test example #2 is a Road Warrior package 1.900" intake, 1.57" exhaust on an 06 casting.
--------Intake------------Exhaust
-------stock---ported---stock---ported
.100---62------69------53------56
.200--125-----137-----112-----124
.300--177-----196-----155-----170
.400--199-----240-----177-----197
.500--209-----256-----184-----210
.600--214-----265-----189-----215


ARN

[STB]

Arn,

Is your craft precise enough so that you can determine the CFM you need on an exhaust and intake port in relation to a particular cam? If so, could you share the major factors you plug into the mathematical formulas/computer programs? Or is it like handgrenades: close works?

Thanks.

Seabrook

[A Atwood]

Originally Posted by STB

Arn,

Is your craft precise enough so that you can determine the CFM you need on an exhaust and intake port in relation to a particular cam? If so, could you share the major factors you plug into the mathematical formulas/computer programs? Or is it like handgrenades: close works?

Thanks.

Seabrook

Seabrook, as I have stated before, I love formulas, calculations, and mathematical equations. When I purchased my flowbench(sf600), I got a manual with many formulas in it that apply to cfm, horsepower, and volumetric efficiency. There is no formula that applies to camshaft timing and flow numbers. The two do not apply together in any single equation. The cam timing is relavant only to displacement, rpm, and port cross section area. When you change the displacement, the cfm requirement at any given rpm changes.
Seabrook, there are, however, formulas as to how to figure out how much cfm is required to produce any given amount of horsepower. While cam timing has a very powerful influence on any engines power curve, the cam timing itself does not have certain levels of cfm requirements due in fact that it can be applied to any number of different engine sizes and port shapes and sizes.
ARN

[fxstc94]

do you port evo heads to