Holes in airbox lid

[Baldini]

Got a K&N filter to put in airbox & was going to drill/cut top. Any views on best way? Lot of little holes or a few big holes or does it really matter?

 

Thanks,

 

KB

[v50man]

Lots of little holes. Calm air = good air.

[BrianG]

I put 6x 1.5" diameter holes.................. 2 rows of 3

[Guest ratchethack]

Keith, looks like you're headed down much the same path as myself. So of course I salute you, Sir! I've got a similar setup to yours - FBF oval carbons with the Stucchi crossover - which I consider entirely acceptable with stock intake, sound-pressure wise. Well, truth be told, the sound is actually a whole lot nicer than "acceptable", but I'm sure that by now you understand exactly...

 

In my case, after finishing up creating much the same exhaust as you've just completed, I decided the way to go was lidless, so I made up a nifty little filter bracket to replace the airbox top.

 

Now, before you start hacking up your airbox, consider yourself forewarned: The open intake honk is FRICKIN' LOUD! Can you say, "tinnitis"? WHAT? WHAT? After a few dozen miles I coudn't take it without earplugs, not to mention the fact that it was running far too lean with the "generic" PC III map (Todd Eagan's #003) that most closely matches my exhaust config. with stock intake.

 

As a result, I went back to the stock airbox top and snorkels, thankful that I hadn't carved it up. As is, the exhaust note crosses the excruciatingly painful threshold only slightly now at WOT - for me, this is just about right. I tend to work the fabulous new & improved torque spread using only about 3/4 throttle anyway.

 

Be sure to advise on your entire experience!

 

Rgds.,

 

Ratchethack

[al_roethlisberger]

I've heard this mentioned many times that the "lidless" airbox modification is so loud

 

I find that interesting, as the pod solution isn't really loud at all... although there are some cool sound-effects

 

 

al

[Baldini]

Thanks for replies. I don't want loads of induction noise so maybe I'll leave airbox stock & just put in K&N. The one thing sticks in my mind is Amadeo @ Raceco once said "the intakes are so small I'm surprised it breathes at all". Does opening the airbox really help? I've used pods on the Tonti for years & like Al, don't find them that loud. Maybe it's the different airflow, perhaps airbox is noisy cos it's still pulling air thru an aperture, maybe speeds up flow? Trouble is I got a dyno appt Thursday so need to get something decided ....

 

Thanks again.

 

KB

[dlaing]

Completely lidless is LOUD.

I suspect that if the area of the holes is equal to or larger than the area of the Wide Open Throttle Bodies, you are gonna be doing better than the stock snorkles.

Throttle bodies are roughly (2) 4cm holes or if we use geometry Area = 3.14 X radius squared, so Area = 3.14 X 4 X 2 = 25.12 square cm or a little less than ten square inches...Not sure how to figure that into drill holes, but maybe about 60 or 70 half inch drill holes...It is late, my math is probably all bad...

Bigger Snorkles may be a better alternative.

[Guest Frankie100Chili]

i have a 2 inch free Snorkles and K & N filter in the original airbox.

 

drilling the lid can it improve the situation?

 

I have a Powercommander and i can adjust the carburation if this becomes too lean.

 

thanks and excuse me for my English.

[Guzzirider]

Keith I have gone the whole hog and have most of my lid cut away.

 

If you are running louder pipes like Mistrals I dont think this makes much of a noise difference in comparison, maybe slightly louder.

 

Have done the same on my Jackal and am pleased with the results on both bikes- if you are noot sure then I guess there is no harm in doing a little at a time- start with little holes then if you want more make 'em bigger!

 

Regards

 

Guy

[Mal]

Keith

 

I ended up cutting most of the lid away (copied a picture I saw on the Raceco website of their V11 airbox modification, figured if Amedeo did it it can't be bad) and as with Guy I did not notice much of a sound increase (I too have Mistrals), certainly not the levels other folk seem to be experiencing.

 

The only down side to cutting the best part of the airbox lid off is that you can't go back to standard whereas with holes you can cover them in strong tape but that doesn't bother me as I've no intention of doing that. One way around this would be to sourse another airbox lid or do as some folk have done and fabricate a frame to hold the filter in place.

 

I have also tried pods (always love to experiment), and I find they do make a lot more noise when you are going for it on large throttle openings, a fair bit more than my open airbox lid, don't know why.

 

Mal

[GuzziHutch]

Noise? What noise? The '03 Lemans has open air box, Power Commander, Stucchi X-over and Guzzi Ti pipes. I ride without earplugs. There is intake noise but overall the V11 Lemans is significantly more quiet than my Lemans III with Bub headers and Lafranconi Wizzer mufflers and also more quiet than the Ducati Supersport with D&D mufflers.

 

The '03 Lemans is also more quiet than the dearly departed Norton Commando and makes a lot of a lot less noise than your typical Harley. So noise? What noise? Make the beautiful music!

 

Joe

[Guest Frankie100Chili]

 

 

like this?

[Guest ratchethack]

Keith, it seems we all have different tolerances to sound pressure. You might try taping the filter in place and going for a spirited ride to get a sense of what an open box is like for you.

 

Ask an old Gunnery Sergeant about the long-term effects of sustained percussive sound pressure. Sure, when he was in his prime, barkin' at the lads, he always said it never bothered him. Now he just says, "WHAT?"

[Guest philbo]

Thanks for replies. I don't want loads of induction noise so maybe I'll leave airbox stock & just put in K&N. The one thing sticks in my mind is Amadeo @ Raceco once said "the intakes are so small I'm surprised it breathes at all". Does opening the airbox really help? I've used pods on the Tonti for years & like Al, don't find them that loud. Maybe it's the different airflow, perhaps airbox is noisy cos it's still pulling air thru an aperture, maybe speeds up flow? Trouble is I got a dyno appt Thursday so need to get something decided ....

 

Thanks again.

 

KB

52569[/snapback]

 

I've got the FBF setup and I'm very happy with it. If things get screwed up, I'll send you my stock lid and you can use that. It's only going to collect dust anyhow.

 

Thanks

 

Phil

[Mal]

like this?

52581[/snapback]

 

yep, thats the one

 

Mal