Factory Pro velocity stacks ?

[NinjaNick]

Oh to live in a world of accuracy.

[schmuckingham]

So maybe this is why my bike kills it on the strait?

The stacks are used to scavenge air, in a small box like in a motorcycle there are two long ones and two shorts ones. The short ones go to the outside of the box were there is less room to suck in air were as the center two have plenty of room. This design is intended to provide even airflow for each cylinder and help a lean or rich condition in the outer two and middle two cylinders.

I woudl say throw a set of stacks on the outside two and see how she runs.....

[RSVDon]

The stacks are used to scavenge air, in a small box like in a motorcycle there are two long ones and two shorts ones. The short ones go to the outside of the box were there is less room to suck in air were as the center two have plenty of room. This design is intended to provide even airflow for each cylinder and help a lean or rich condition in the outer two and middle two cylinders.

I woudl say throw a set of stacks on the outside two and see how she runs.....

Um what? I've never seen a bike with differing size stacks from the inside to the outside. As far as I know velocity stacks have to do with smoothing incoming air, accelerating incoming air slightly, and there's some other things involving pressure waves that I still don't understand yet.

I've never heard of anyone using stacks to account for a lean/rich condition.

[schmuckingham]

Um what? I've never seen a bike with differing size stacks from the inside to the outside. As far as I know velocity stacks have to do with smoothing incoming air, accelerating incoming air slightly, and there's some other things involving pressure waves that I still don't understand yet.

I've never heard of anyone using stacks to account for a lean/rich condition.

they dont account for it, it helps distribute air evenly were the outside cylinders dont have priority flow over the two inside ones. Reomove the stacks all together and you have two cylinders getting air more than the other two.

If the stacks were in open air then all cylinders would have the same length stacks, but some bikes have a un-even air box

[Moto-Brian]

Um what? I've never seen a bike with differing size stacks from the inside to the outside. As far as I know velocity stacks have to do with smoothing incoming air, accelerating incoming air slightly, and there's some other things involving pressure waves that I still don't understand yet.

I've never heard of anyone using stacks to account for a lean/rich condition.

Stock on at least the GSXRs and most the other modern bikes I have seen have different height stacks. Usually taller in the middle...

I have to agree it is due to the fact that the outside edges are closer to the top or lid of the airbox and are shorter to compensate.

Guys "tune" with different heights, but again, it is minimal and usually a wasted expense unless you are a full blown race motor and fighting for the top rung on the ladder in a National setting. Everyone else? Run 'em stock.

[shittygsxr]

Factory Pro velocity stacks worth the $225.00

specs so far on bike would be full Ti-force Bmc filter and power commander.

I did the cam swap on my 750 which includes an gsxr 1000 intake cam on the intake side of your head and the 750 intake cam moved to the exhaust side. the whole conversion should cost about $250 and a lot of patience.

if you want good power contact "tim radley" on the gixxer.com board. He does some awesome projects. He even made a big bang 750 for a magazine. He does a lot of head work including epoxy where they basically shrink and reshape the intake and exhaust tracks on the cylinder head.