Velocity stacks- Yes or no?

[Guest ckamin]

I am contemplating some velocity stacks over doing an air box conversion- any thought? While this will help breathing on the intake side, its more for cosmetic than squeezing every possible pony from the engine. Any pros/cons for the velocity stacks?

 

Also, are there any smooth one out there? The only ones I have found so far have some ball-milled indents around the circumference. And do I need the stacks, or could I just attach the K&N type filter to the throttle body? I don't care much for the look of the foam (Uni?) filter.

 

Thanks!

-Carl

[Guest ratchethack]

I'm assuming you're asking about open stacks, since with filters, intake runners are generally referred to as - well, intake runners or air horns? And intake runners with filters on 'em that are generally referred to as "pods" are not velocity stacks. If so, RE: open velocity stacks:

 

Pro - As a cosmetic consideration only, it looks "racy". Offers a few more hp than filtered air, measurable only at WOT. The hot setup for the Mulsanne Straight or drag strip, where engines are run wide open for sustained periods, and there is no concern about engine wear because engines are built to be rebuilt or thrown away after a few races. For a non-racing Guzzi, it begs the practical consideration, "How much engine operating time is to be spent at sustained WOT?"

 

Con - For road use, it couldn't be more unwise IMHO. Greatly increased engine wear due to ingested airborne abrasives and contaminants. Shortens the life of a road-going Guzzi engine more effectively than running without an oil filter.

 

Just my

[RacerX]

This rumor just won't die... I have substantiated proof that pod filters offer NO benefit over an open-lid airbox (2 or 4 valve motors), and in fact show significant power loss of say 4~5 hp (compared to the open airbox) in the mid-range part of the powerband.

 

However, if you're doing it purely for cosmetic reasons... go forth.

 

End of story.

 

$.02 Todd

[richard100t]

I have pod filters for purely cosmetic reasons & I think they look great. I could care less about the insignificant gain or loss of power either way. I also took the side covers off to show off th WP shock with the k&n pods. That airbox imo is too large & covers up the underside of the tank/top of the engine. Btw I got a set of NGK racing plug wires & think they look pretty cool on the bike also. Seat of the pants riding the bike seems to run smoother but that could be my imagination. Spending $40 on 2 plug wires will make you Want to think theyre better in some way lmao

[Guest ckamin]

No, I wouldn't run anyhting on the street (or track, for that matter) without a filter. I was just contemplating it as I could remove the side panels and get that "in your face" air filter look, but I might just go with a midified airbox afterall. Who knows?

 

-Carl

[Guest ratchethack]

Carl, sorry, you threw me off with "velocity stacks". FYI - though others seem to like 'em, some, including me, have not been happy going to an open top airbox. In my case, the intake roar was excruciating (no other word for it), and I run FBF oval carbons cans that don't bother me from a sound-pressure consideration. I couldn't ride with an open top airbox without earplugs, and that ain't happenin'.

[Guest drknow]

This rumor just won't die... I have substantiated proof that pod filters offer NO benefit over an open-lid airbox (2 or 4 valve motors), and in fact show significant power loss of say 4~5 hp (compared to the open airbox) in the mid-range part of the powerband.

 

However, if you're doing it purely for cosmetic reasons... go forth.

 

End of story.

 

$.02 Todd

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Todd, I thought there was info out there to that effect. Do you have dyno sheets comparing pods to open lid airbox? There was a recent thread on the Centauro Owners forum and everyone there swears by the pods OVER the airbox. I'm confused again...

 

dk

[Alex-Corsa]

Carl, sorry, you threw me off with "velocity stacks".  FYI - though others seem to like 'em, some, including me, have not been happy going to an open top airbox.  In my case, the intake roar was excruciating (no other word for it), and I run FBF oval carbons cans that don't bother me from a sound-pressure consideration.  I couldn't ride with an open top airbox without earplugs, and that ain't happenin'.

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Are these FBF cans "open" or normal, what is the configuration of the exaust including the crossover.

 

I am running in a "open" crossover and "normal" factory Lanfranconis.

Yet I would like to change to some Mistral oval or round carbon cans mostlly for the sound and weight difference. I don't want to put some open cans, is this configuration open crossover-normal cans right or should the whole thing has to be open? I have heared different opinions (yet this configuration on my bike now is tunned from Dynotec and I would't concider that they're wrong in what they did, but I don't know exactlly the benefits of such a configuration.)

I do have a K&N filter on the airbox.

[Guest ratchethack]

Alex, if I understand your interest correctly, the FBF oval carbons are "open" in that they have an unobstructed, straight passage the width of the inlet pipe from inlet to exhaust, with the usual perforated sheet metal separation from the surrounding packing. Both FBF cans together weigh less than one stock LaFranconi. I also run a Stucchi crossover, which is also "open". This configuration puts the flow bottleneck squarely on the airbox, which is without question now the limiting factor to flow at WOT in my config. I have no doubt that I'd gain fairly significant hp and torque with an open top airbox, but per above, the intake honk's just too gruesome , and I'm neither racing nor running around at WOT (ever) so I figure I'm not missing much. I didn't buy a Guzzi to chase after big power to compete with the latest krotch rockets anyway. (Let's face it - for the most part this is just an exercise in futility ). A re-map of the PC III would also be required for me to go to an open-top airbox.

 

Like you, I had previously run the Stucchi crossover with the stock LaFranc's for a year or so. As you know, the stock LaFranc's are not an "open" design. The Stucchi added a nice little boost to torque in the midrange at 4-5K RPM and increased sound levels slightly by adding a deeper tone that was noticeable through the stock LaFranc's.

 

IMHO, on a well-tuned Guzzi, the FBF oval carbons and Stucchi x-over together make the best exhaust notes in all of motorcycling , but that's just me, and as always, YMMV.

[felix42o]

IMHO, on a well-tuned Guzzi, the FBF oval carbons and Stucchi x-over together make the best exhaust notes in all of motorcycling , but that's just me, and as always, YMMV.

 

I have to agree- just bought my first Guzzi, an 02' Tenni, with the same exact package and, after two Ducatis and a lot of Hondas and such, I'm beside myself. The bike's awesome.

Brian

[al_roethlisberger]

One clarification.... keep in mind that there is something of a hybrid solution if you like.

 

You can put the pod filters over the stock intake-runners/stacks that protrude into the OEM airbox. It takes some work to stretch them over the bell end of the runners, but this may(or may not) be of some benefit over just putting the pods directly on the throttle body ends, even with the K&Ns like mine that have something of a "runner" or "throat" built-in

 

 

But this is just speculation on my part.

 

al

[Alex-Corsa]

Like you, I had previously run the Stucchi crossover with the stock LaFranc's for a year or so.  As you know, the stock LaFranc's are not an "open" design.  The Stucchi added a nice little boost to torque in the midrange at 4-5K RPM and increased sound levels slightly by adding a deeper tone that was noticeable through the stock LaFranc's.

 

IMHO, on a well-tuned Guzzi, the FBF oval carbons and Stucchi x-over together make the best exhaust notes in all of motorcycling , but that's just me, and as always, YMMV.

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Thanks for your answer. Gives me the prespective of somehing else.

Though as it seems to me perhaps I'll keep it that way as it is now.(for the moment)