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Posted by: RonD Sep 17 2012, 11:35 PM

For me the induction noise of carbs is too loud. So I went looking for a solution and I thought I would share what I found and trying. 1985 Honda 1200 Goldwing air cleaners.

They seem to be working great. Nice deep sound and quieter. The air horns on top are about 1"x 1 1/2" each. Combined they are bigger then 1 throat of the carb. I don't feel any reduction in power and idle seems about the same. Engine is a basic rebuilt 1.7 to 2.0L specs with carb cam and hydralic lifters.

Cheap too. shipping cost more than the air boxes themselves. A little fabrication of a mounting plate, but pretty much bolt on. Linkage clears.


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Posted by: '73-914kid Sep 17 2012, 11:46 PM

Whats the height of the box from the base at the carb to the highest point?

Posted by: euro911 Sep 18 2012, 12:15 AM

They actually look like they belong in there.

How much quieter are they (if you can attach a percentage to them)?

Do they clear a stock rain tray OK?

How did you take out the gap with the different height elements?

Posted by: RonD Sep 18 2012, 06:57 AM

They are about 6 1/4" tall. I don't have a rain tray to check clearance but I would suspect they would touch.

The top of the Honda filter has a depression which makes it about the same height as the weber filter. So it just fits.

They are very quiet, better than 50%. Almost silent at low RPM. The sound is not thumpy at higher revs. More uniform, with a bass note.


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Posted by: euro911 Sep 18 2012, 11:11 AM

Nice mod, Ron. Thanks for posting

I don't want to lose my rain tray, so if they don't fit, I'll need to look for another solution

Posted by: Dave_Darling Sep 18 2012, 11:18 AM

Very cool! This looks like a really worthwhile addition for anyone who uses a carb'ed 914 on the street.


.... Or one with independent throttle bodies in any way...... Hmmmmm.....

--DD

Posted by: yeahmag Sep 18 2012, 11:32 AM

These would negate most of the reason for having a rain tray with carbs... Would they not?

-Aaron

Posted by: Vacca Rabite Sep 18 2012, 11:38 AM

Rain tray also protects the electrical wiring and keeps water out of the engine bay in general. If you run w/o a tray you need to be sure the battery is covered so you are not leaching watery battery acid back down into the hell hole.

Zach

Posted by: yeahmag Sep 18 2012, 11:43 AM

The battery is exposed regardless of having a rain tray or not.

Posted by: JmuRiz Sep 18 2012, 12:13 PM

Those air cleaners are really cool...they'd look good if you had some side-draft carbs (on other cars). I remember seeing a really cool Mercedes M110 with side-draft webers on it, for a daily driver those covers would be perfect.

Posted by: wobbletop Sep 18 2012, 12:15 PM

Anyone found anything for a -6?

Posted by: SirAndy Sep 18 2012, 12:24 PM

The rain tray does not really protect the battery much anyways ...

Posted by: SirAndy Sep 18 2012, 12:24 PM

Porsche. It's called a "911" ...

Posted by: euro911 Sep 18 2012, 12:25 PM

My battery has a plastic cover (came with the AA battery tray/mount kit), but I like the rain tray because it catches most of the rain water should I encounter an impromptu storm (like the evening we came home from the Rt-66)

I think with the GL housings by themselves, the carbs could still ingest a fair amount of water without a rain tray in place. I know a few folks who have the fiberglass 'hats' (and no tray) and have ingested water while parked.

Maybe a custom (shallower) tray is one solution


EDIT:
Old 911s don't have rain trays due to the lack of space from the stock air filter housing, but there is an optional tray for 912s.

Posted by: '73-914kid Sep 18 2012, 12:25 PM

Have you noticed any difference in the air/fuel ratio after installing them? I'm in desperate need of quieting my carbs down with my school commute every weekend... This is a great option, thanks for sharing!

Posted by: Vacca Rabite Sep 18 2012, 01:02 PM

Air cleaners off a 912 work, and can be adapted to fit IDFs.

Before I decided to go FI, this was the route I was going to take.

Zach

Posted by: euro911 Sep 18 2012, 03:24 PM

I have a few sets of those, but they're set up for Solex P40IIs. I'll check to see if they fit Weber IDFs

Posted by: gothspeed Sep 18 2012, 03:35 PM

Looks good

Posted by: RonD Sep 18 2012, 03:41 PM

I balanced and tuned carbs after I put them on and watched my idle very closely and really didn't see much of a differance between putting the tops on the filters and the air box top with the horns. Driveablilty wise there are no flat spots that I can tell. We have some pretty steep canyon roads here in Boulder and it pulled real strong from low RPMs.

I probably spent less then $75 on the project. The 356 or 912 air cleaners I saw for sale were $200 plus and needed adapter plates to work with Webers, and didn't seem to quite fit anyway.

I thought of motorcycles because I have a BMW R90/6 which is essentially half type 4 engine and its super quiet. BMW boxes need more fabrication to fit, so just kept looking and found these. The earlier Goldwing boxes are not as tall and might work also


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Posted by: ldsgeek Sep 18 2012, 04:20 PM

The GL1000 (shown by RonD), GL1100 and GL1200 should all have something similar. this is a great idea. For those who don't know the setup, this bolts to the top of the air plenum that connects the 4 carbs on these bikes. Any cycle salvage place (Coopers is in Franklin, NH near me) should have these available.

Posted by: KaptKaos Sep 18 2012, 04:43 PM

Nominate for classic thread status. This is a common issue, with a very innovative solution.

Nice job!

Posted by: Gint Sep 18 2012, 05:39 PM

Interesting. Hmmm....

Seems like you could fab up a couple of air boxes out of sheet aluminum or galvanized steel without too much trouble also.

Posted by: ClayPerrine Sep 18 2012, 05:45 PM

I took the stock air cleaner off my six and put on K&N watershield air cleaners because I like the sound of the six stacks at full song.


Just got to listen to it too. My car is back up and running.

Posted by: 02loftsmoor Dec 27 2012, 01:28 PM

nice out of the box thinking! a clean look

Posted by: Cap'n Krusty Dec 27 2012, 01:38 PM

Well, there's the one designed and installed by Porsche ..................

The Cap'n

Posted by: wobbletop Dec 29 2012, 07:41 PM

I'm new to this stuff. I guess you're referring to the Zenith covers? Would a particular model fit a 3.0 with webers?

Posted by: Dave_Darling Dec 30 2012, 02:14 AM

The triple Webers in the 914-6 used a single combined air cleaner. Almost the same as the one from the 1969 911T, which makes sense because the Six motor is almost identical to the 69 T motor.

I'm pretty sure that's what the Cap'n was referring to.

--DD

Posted by: Mark Henry Dec 30 2012, 07:42 AM

I'm to believe any /6 carb airfilter assy. will fit but you might have to cut off the snorkel.
Is this correct?

Is the bolt pattern the same on both the zenith and weber carb tops?

Posted by: JamesM Dec 30 2012, 08:26 AM

CB performance sells covers for use when turbocharging, why not just run them without the turbo? They have a bunch of different models including a low profile one for 356s that might fit under a rain tray. Looks like it would be easy to pipe the inlets whereever you want.


http://www.cbperformance.com/ProductDetails.asp?ProductCode=7313T

Posted by: euro911 Dec 30 2012, 11:45 AM

Interesting


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Posted by: kgruen2 May 1 2017, 12:59 AM

I know this is a very old thread, but...........In the case of the Honda Goldwing air boxes, does it matter which way the air intake horns are pointed, towards the front or the rear?

Posted by: porschetub May 1 2017, 02:23 AM

No makes no difference,I like this idea for a 4 just makes sense,the sound is fun for a while....
I feel lucky to have a six with stock air cleaner ,hate to have to buy one they are getting a bit crazy pricewise.
Always like the Alfa setup for Dellorto's and Webers on the early carb cars no reason it won't work on a T4 without simple mods.

Posted by: michael7810 May 18 2017, 03:07 PM

I just finished with the same mod and couldn't be happier. Cost of the filter boxes off eBay was $24 each including shipping and I used 85 Gold Wing Aspencade 1200cc boxes. I've driven about 10 miles and did not notice any changes in A/F, idle speed or power. I did notice a HUGE reduction of intake noise and now I can hear the exhaust. The ultimate test is driving up an incline on the highway with the windows up which I will attempt sometime before WCR. Below are a few pictures of how it goes together...basically as RonD describes. And thanks to Keith914 who gave me his lessons learned.

Mounting plate made from 1/8" aluminum:



Before installing the old K&N-type filter. You can't see it here but I had to grind off the ends of the chrome bottom plate to fit the GW air box opening.



With filter cover installed...I had to weld in a longer 1/4-20 bolt for the wing nut and dimple the top of the chrome top to make it all fit properly:

Posted by: 7TPorsh May 18 2017, 04:37 PM

Congrats! I did this mod too and I met a fellow from Laguna Beach at the G&R Swap that had it as well.

This is an easy 80% reduction of intake noise and I highly recommend this mod to everyone.

Posted by: Elliot Cannon May 18 2017, 07:47 PM

I like the noise my carbs make. Especially when I'm wearing these.


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Posted by: Beach914 May 18 2017, 08:07 PM

That was probably Keith914. He made the same set up for his t4. But now he's doing his six project.

Posted by: lonewolfe May 18 2017, 08:26 PM

Those CB Covers are made to go with an air box. Those covers have no filters inside. I've been thinking about gabbing an air box attached to the covers with silicon hoses.

There's a company in Germany with a similar setup as I've been working on. They are call CSP Performance. Their airbox kits start at 799.00 Euro's if I'm not mistaken but items a chunk of change for a plastic airbox, carb covers, silicon hoses and hardware.

Posted by: euro911 May 29 2017, 12:17 AM

Yeah, I looked into those CB covers way back when, and still might go that route if I keep the 'BB' after finishing up the '71 (which has F.I.)

It'll be project# 1,785