Velocity Stacks and new painted parts!

[Dr_Dosh]

I bought some Velocity Stacks about two weeks ago and will get them sometime next week. I was just wondering if any one has any tips to installing them due to the fact that I was told they don't come with any instructions. I looked it up on the all mighty YOUTUBE.com and could not find any instal vidz.

OH, I will post some new pics soon as well. I painted the hugger my two bros rear cap it gotta kinda beat up on a ride so I ended up re-doing it. I also did the little plates that lock under the seat.

[Chef]

1) Prop up tank w/ tank prop from the trunk/tail section ( that metal rod thats in their )

2) Undo all 4 clamps that hold the airbox onto the throttle bodies and dis-connect all hoes and sensors from the airbox and take it off the bike.

3) Un-screw all the screws that are on top of the airbox and their should be one in the center as well and take the lid off.

4) Take the rubber boots out of the airbox

5) Install new rubber boots and put the velocity stacks into the boots .


Which stacks did you get ? Yosh or Factory Pro ? Not sure if the yosh stacks have a specific placement for each stack. I know factory pro says you can install them either way i.e. 2 tall stacks on the inside and 2 small stacks on the inside . or 2 tall stacks on the inside and 2 small stacks on the outside.

Let us know if there is any HP gain, ive heard 5 or so, but they make your bike sound beastly!

[Dr_Dosh]

Thanks man, I got Factory Pro.

[Dr_Dosh]

.

[Dr_Dosh]

.

[yagenrok636]

No way its a 5hp gain. It will make it sound good for sure tho. Bike looks really good Dosh, PhD.

[Zach!]

Two shorts and two talls? On the Hondas the velocity stack mod replaces them with all shorts.

[yagenrok636]

Its interesting, different size (length and diameter) velocity stacks produce different results. Its not that just creates more air flow, because you the opposite - that it restricts additional mass. For ex. - extending your tailpipe another 6" doesn't ADD horsepower, so why would extending your intake be any different?
I've researched this off and on for a long time in an effort to build the most horsepower. I bought John Lingenfelter's "On Modifying Small-Block Chevy Engines" back in high school and he is revolutionary on the topic (in my opinion).

First, its important to understand several of his horsepower "Laws."
1. Always maximize power within the RPM band where the engine spends its most time.
2. Vehicle application is far more important than most enthusiasts would believe.
3. Bigger is rarely better. Relatively speaking, "small" intake ports, manifolds, and exhaust systems maximize torque which improves that wonderful "seat-of-the pants" feeling in street engines.
4. Port velocity will improve cylinder filling more efficiently, especially at and below peak torque, than big flow numbers generated by large, slow-moving ports. (Directly related to velocity stacks!!!!!!!!)
5. A strong cylinder head will always make more power even if poorly matched with the cam. A weak cylinder head matched with an optimized cam will never perform as well.
6. Transmission and rear-end gear (or sprockets) ratios have a significant impact on engine component decisions. A good example of this is camshaft selection charts that emphasize cruising rpm - basing, in part, a cam profile on gear ratios.

Blah, blah, blah, ANYWAY, Lingenfelter talks mainly about intake manifolds in size and length being the "organ pipe". Its a constant regardless of carb or fuel injection. Think of it as a trombone changing pitch with different positions. I think we can learn a little, regardless of V8 single cam application. Straight from the book, Intake Runners:

"Condensing this very complex subject down to its basic concepts, increasing [intake manifold] runner length tends to improve engine torque at the lower rpm levels while simultaneously lowering the peak torque RPM point. Since there are very few free lunches in this world, the downside to increasing low RPM torque is a subsequent loss of horsepower occurring usually at a lower peak RPM. At the other end of the spectrum, an extremely short runner intake offers improved power levels at higher RPM levels, sacrificing power usually below peak torque in favor of the higher RPM levels."

[yagenrok636]

Cross-Sectional Area:

The other half of the intake manifold design process, cross-sectional area of the port, also plays an important part. Generally, a smaller runner area increases intake charge velocity, speeding up the inlet charge, which improves cylinder filling (expressed as volumetric efficiency) at lower RPM levels. Conversely, huge intake manifold port runners contribute to slowing the intake gas speed at lower RPM levels, hurting power below peak torque while contributing to improved cylinder filling at RPM levels closer to peak horsepower.
Its important to remember that horsepower is merely a function of torque at a higher RPM where there is less time to fill the cylinder.
Obviously, the key is configuring the engine to flow vast amounts of air in a very short amount of time.

With this being said, I would suggest, for track applications, a short/wide velocity stack for HP at high RPMs. For street applications, more torque is necessary for a better rounded riding experience, so taller/narrow intakes can be used.

ALSO, the exact opposite can be said for exhaust manifolds!!!! (Headers, connect pipes, mufflers) I know a lot of you like to shorty your pipes! I know, I did it too! But Lingenfelter clearly states that the opposite is effective. Short pipes create lower RPM torque and hurt high RPM horsepower! Increasing pipe diameter however, helps build HP at high RPMs.

Long post! But I figured it was just a good FYI for anybody interested.

-Rob

[Zach!]

Thanks Rob, I remember my buddy Mike always had that book in high school, it was his bible haha. So Dr.'S stacks are a best-of-both-worlds application...getting those low RPM numbers beefed up, while helping out the high RPM horsepower numbers with the tall stacks.

[Chef]

No way its a 5hp gain.

Yeah i figured, i guess my friend had to justify to me why he put them on

[Dr_Dosh]

WOW, thanks alot

[Dr_Dosh]

factory pro put the 2007 on the EC997 (best dyno on the market) and pulled an extra 4.5 hp at ~15,000 rpm but the hp increase on the dyno starts at 12,000
you also have a gain between 8,000 and 10,000 of about 1 to 1.5 hp

Today they will be introduced to the bike they will spend the rest of there life with!

[yagenrok636]

i'd like to see all the other mods to that bike too. If you do nothing but K&N and velocity stacks, I'm sure you'll get 5hp. Just like if you did JUST a muffler. But if you do both, it doesnt mean you'll get 10hp. You still just get 5...

Stock equipment is restrictive. But you dont get 5hp for every mod you do. So if that was a totally stock bike with stacks and a filter, I can see 5hp easy...

[Dr_Dosh]

here are some pics of the install. Kinda was a pain in the ass