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914World.com _ 914World Garage _ Quiet Down A Dual Carb Engine..It Works
Posted by: 7TPorsh Mar 16 2016, 11:13 AM
Finally fixed my exhaust leak so a little more quiet but my carbs scream!
I have seen the expensive airbox for sale around $900 but has anyone found any other solution?
I am thinking of using the Turbo Hats and running the input tube bellow the engine tin to a cone filter.
Or are there any type of plastic molded airboxes out there that I can graft the weber bottom plate to?
Running the open K&N filter housings.
Ideas?
Posted by: SirAndy Mar 16 2016, 11:33 AM
Switch to FI ...
Posted by: rgolia Mar 16 2016, 11:38 AM
Gary,
The CSP airbox I recently installed was $750 shipped. What a difference. I would think you could make something up similar for a lot less, but it will take some work. I do not know if you looked at my thread, but it really looks nice.
Posted by: 7TPorsh Mar 16 2016, 12:11 PM
Gary,
The CSP airbox I recently installed was $750 shipped. What a difference. I would think you could make something up similar for a lot less, but it will take some work. I do not know if you looked at my thread, but it really looks nice.
Yes it looks awesome but a little too much $$$. Hoping there are existing boxes out there that could be modified. Maybe the air filter housing off an injected car.
Posted by: r_towle Mar 16 2016, 12:17 PM
two CB Performance turbo hats for the carbs.
One mid 70's VW beetle air filter box.
Some 3 inch plastic tubing.
Similar to the CSP box, you can make one that does the same thing.
The turbo hats go on the carbs (duh)
The tubing needs to be drilled into the side of the beetle airbox, then clamped to the turbo hats.
What you gain is noise reduction, and if you look around, this has been done before.
I have no clue where the links are...but I did find it years ago when I had sticker shock regarding the CSP airbox solution.
rich
Posted by: wes Mar 16 2016, 12:23 PM
two CB Performance turbo hats for the carbs.
One mid 70's VW beetle air filter box.
Some 3 inch plastic tubing.
Similar to the CSP box, you can make one that does the same thing.
The turbo hats go on the carbs (duh)
The tubing needs to be drilled into the side of the beetle airbox, then clamped to the turbo hats.
What you gain is noise reduction, and if you look around, this has been done before.
I have no clue where the links are...but I did find it years ago when I had sticker shock regarding the CSP airbox solution.
rich
Would be cool if that link should show up!
Posted by: r_towle Mar 16 2016, 12:25 PM
feel free to use google for an hour and find it...
good things come to those who put in the effort.
Rich
Posted by: Mark Henry Mar 16 2016, 12:37 PM
Would be cool if that link should show up!
I often find doing a search through google works better than the search on this site.
Use the first term "914world" then your search words.
Posted by: Elliot Cannon Mar 16 2016, 12:55 PM
I love the way my carbs sound. But then again, I drive with these. 
Attached image(s)
Posted by: rgolia Mar 16 2016, 01:14 PM
How about these
http://www.914world.com/bbs2/index.php?showtopic=95755&st=0&p=1170158&#entry1170158
http://www.914world.com/bbs2/index.php?showtopic=110167
Posted by: JmuRiz Mar 16 2016, 05:44 PM
912 air boxes would be the easiest to find (I would think)
Those units from BAS and CSP are great looking!
Posted by: wndsrfr Mar 16 2016, 07:33 PM
Ideas?
Somewhere I saw someone using Honda Goldwing? (maybe) air filters to cut the induction noise....maybe 3 years ago or so......
Posted by: RickS Mar 16 2016, 11:00 PM
Put two layers of a light weight Dynamat like product behind the back pad to reduce noise but my carbs aren't screamers, it's just induction noise.
Posted by: 7TPorsh Mar 17 2016, 09:03 AM
Ideas?
Somewhere I saw someone using Honda Goldwing? (maybe) air filters to cut the induction noise....maybe 3 years ago or so......
Bingo! I had this in the back of my head too just couldn't recall through the fog.
I just purchased a pair off ebay for less than $30 shipped so this will be the project.
http://www.914world.com/bbs2/index.php?showtopic=194570
Posted by: 7TPorsh Mar 17 2016, 09:15 AM
As I have done some research overnight it seems that the breather boxes from the 1984-1987 Honda Goldwing 1200 are the ones.
My original thought was to have these type of boxes fed by a common cold air tube but I like how this setup is, nice and clean. I think these molded boxes will do more noise reduction than metal ones like the turbo hats.
Posted by: rhodyguy Mar 17 2016, 10:00 AM
can you provide a link to the picture of the gold wing parts?
Posted by: 7TPorsh Mar 17 2016, 02:43 PM
can you provide a link to the picture of the gold wing parts?
Here is the ebay search page...you just need 1984-1987 Honda Goldwing 1200 air breather box....probably available outside ebay and at the picker part.
http://www.ebay.com/sch/i.html?_odkw=goldwing+air+1200&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xgoldwing+air+1200+box.TRS0&_nkw=goldwing+air+1200+box&_sacat=0
Posted by: aircooledtechguy Mar 17 2016, 03:32 PM
thedubshop.net made this recently and it really quiets it down.
Posted by: veltror Mar 18 2016, 01:22 PM
http://www.gwd-weiser.de/?page_id=343
Posted by: moorepower Mar 18 2016, 02:58 PM
thedubshop.net made this recently and it really quiets it down.
The std calculation is for every 10 degrees F you loose 1% H.P. They look nice, but...
Posted by: nathansnathan Mar 18 2016, 03:10 PM
I finished putting mine together - i got the parts at Pacific customs;it was expensive. I don't know how well it all works as I need to figure out some linkage to run it. .. made it for my bus. 
Posted by: rhodyguy Mar 18 2016, 03:25 PM
WOW! BIG! A CFR cable setup or center pull might be the way to go.
Posted by: 7TPorsh Mar 28 2016, 10:59 AM
One arrived in the mail....bigger than I pictured. Hoping to get the other tomorrow.
I looks like I will need to fashion a baseplate to attach the new housing to the carb. The old KN plates are too small to cover the opening.
Posted by: 7TPorsh Mar 28 2016, 11:01 AM
Also ordered Honda air filters
Posted by: 7TPorsh Mar 28 2016, 05:35 PM
As I stare at this I am seeing another possible modification for Phase 2 after I get the stock boxes installed....and i want to put my rain tray on at some point.
The stock Honda boxes with tops won't clear the rain tray....but the bottom housings with a custom flat top WILL allow a rain tray. My thought is make a top out of flat Lexan that holds down with a wing nut and seals the air filter...top of the KN Porsche filter lines up perfect and the velocity stacks clear.
Cut a 3.5" hole in the side of the housing base on the outside. Plumb a 3.5" "cold air" pipe down through the existing heater tube holes in the tin. If you have heat maybe to rear wheel well?
These modified housing would use air filters so there isn't a need to have a cone filter in the setup...just a place to pull in air.
Posted by: 914forme Mar 28 2016, 05:53 PM
Your plan means you will be drawing hot engine air into your carb. See how it does with out a warm air system.
Posted by: JimN73 Mar 28 2016, 06:05 PM
As I stare at this I am seeing another possible modification for Phase 2 after I get the stock boxes installed....and i want to put my rain tray on at some point.
The stock Honda boxes with tops won't clear the rain tray....but the bottom housings with a custom flat top WILL allow a rain tray. My thought is make a top out of flat Lexan that holds down with a wing nut and seals the air filter...top of the KN Porsche filter lines up perfect and the velocity stacks clear.
Cut a 3.5" hole in the side of the housing base on the outside. Plumb a 3.5" "cold air" pipe down through the existing heater tube holes in the tin. If you have heat maybe to rear wheel well?
These modified housing would use air filters so there isn't a need to have a cone filter in the setup...just a place to pull in air.
You can download a decibel app to your favorite electronic device and quantify the difference between the existing and new systems. Might be good info.
Posted by: 7TPorsh Apr 4 2016, 10:51 AM
Well they are on the car and I can't be happier. I made a pair of base plates and fabricated a hold down using some plate steel and a carriage bolt and voila!.
Posted by: 7TPorsh Apr 4 2016, 10:58 AM
But here's the kicker. I started the car and went for a drive and it sounds awesome. I would say a 70% noise reduction from the intakes; I can hear the header now.
Here's the comparison....same street....pardon the shift clunks....trying to hold the phone, steer, shift, gas......
BEFORE:
https://www.youtube.com/watch?v=zH2VVcBJlzI
AFTER:
https://www.youtube.com/watch?v=wEEkFp5U6Tw
AFTER ON ANGELES CREST
https://www.youtube.com/watch?v=iuXd1U63at4
Posted by: rhodyguy Apr 4 2016, 11:59 AM
Very quiet now. VERY nice for a full day behind the wheel. The 2 horned ends on the top are for induction yes? How much were the GW filters?
Posted by: 7TPorsh Apr 4 2016, 12:27 PM
Very quiet now. VERY nice for a full day behind the wheel. The 2 horned ends on the top are for induction yes? How much were the GW filters?
Horns on top are the intakes. I used the K&Ns I had since the Honda paper filters I bought were a little too small and didn't clear the velocity stacks. The K&N seal down tight.
The pair of boxes were around $35 delivered....if you don't use velocity stacks the Honda paper filters will work....filters are about $10 each.
Posted by: 7TPorsh Apr 4 2016, 12:30 PM
It's so much quieter I have to watch the tach so i don't over rev. The difference is like going from someone yelling in your ear to someone yelling 20 ft from you with their hands over their mouth...
Posted by: rhodyguy Apr 4 2016, 12:34 PM
Are those the 2 1/2"ish VC stacks? For a long day in the drivers seat I resort to foam ear plugs.
Posted by: SA-914 Apr 4 2016, 12:40 PM
What size KN filters did you end up with?
Posted by: rhodyguy Apr 4 2016, 12:47 PM
Rain tray interference...are you using CB tall intakes or short ones?
Posted by: 7TPorsh Apr 4 2016, 12:59 PM
Yes there will be interference with the stock rain tray. I think I have the tall intakes. I eventually will probably make up some sort of shallower tray but for now the car isn't driven in the rain so not an issue.
The K&N filers are the ones I had with the chrome weber housings. Shown in the picture above.
Posted by: 7TPorsh Apr 4 2016, 01:01 PM
The Honda filters are not quite as long.
Posted by: 7TPorsh Apr 4 2016, 01:02 PM
Are those the 2 1/2"ish VC stacks? For a long day in the drivers seat I resort to foam ear plugs.
Yep. 2.25" stackers
Posted by: Bossman Apr 4 2016, 08:19 PM
This looks great. I just ordered a set off EBay.
Posted by: Bossman Apr 4 2016, 08:24 PM
As I stare at this I am seeing another possible modification for Phase 2 after I get the stock boxes installed....and i want to put my rain tray on at some point.
The stock Honda boxes with tops won't clear the rain tray....but the bottom housings with a custom flat top WILL allow a rain tray. My thought is make a top out of flat Lexan that holds down with a wing nut and seals the air filter...top of the KN Porsche filter lines up perfect and the velocity stacks clear.
Cut a 3.5" hole in the side of the housing base on the outside. Plumb a 3.5" "cold air" pipe down through the existing heater tube holes in the tin. If you have heat maybe to rear wheel well?
These modified housing would use air filters so there isn't a need to have a cone filter in the setup...just a place to pull in air.
If you're not running heat how about usin the existing heater tube holes to run the "cold air" intake pipe out in front of the engine, under the car (next to the air deflectors?) for a cold air/ram air type set up
Posted by: 7TPorsh Apr 4 2016, 08:51 PM
As I stare at this I am seeing another possible modification for Phase 2 after I get the stock boxes installed....and i want to put my rain tray on at some point.
The stock Honda boxes with tops won't clear the rain tray....but the bottom housings with a custom flat top WILL allow a rain tray. My thought is make a top out of flat Lexan that holds down with a wing nut and seals the air filter...top of the KN Porsche filter lines up perfect and the velocity stacks clear.
Cut a 3.5" hole in the side of the housing base on the outside. Plumb a 3.5" "cold air" pipe down through the existing heater tube holes in the tin. If you have heat maybe to rear wheel well?
These modified housing would use air filters so there isn't a need to have a cone filter in the setup...just a place to pull in air.
If you're not running heat how about usin the existing heater tube holes to run the "cold air" intake pipe out in front of the engine, under the car (next to the air deflectors?) for a cold air/ram air type set up
Now that they are in. i see after an hour long drive the engine compartment is really not that hot. the boxes and the baseplates i made do not retain any heat whatsoever. i think the intake air is as cool as it can probably get without re-plumbing the car. for an LS1 yes but this engine not worth it.
this is by far the best mod i have done on the car; better than the bump steer kit!
Posted by: simonjb Aug 30 2022, 07:46 AM
I have been looking at options for this as well.....
1) I thought the CSP set up was perfect (not cheap). They have two on their site - one for a type 4 Beatle and one for a type 4 Bus. I contacted them and they said neither works for a 914
2) I like the Honda set up also - and much cheaper - but I can't seem to find what else I need to make them work - aka - the attachment plates?
Anyone else looked at this recently?
Thanks !
Posted by: Root_Werks Aug 30 2022, 09:47 AM
I used a set of 912 aircleaner housings on a carb'd 914-4 once. Worked nice, couldn't use the rain tray if I remember correctly.
Posted by: rgolia Aug 30 2022, 10:01 AM
The one for the bus fits perfect with the rain tray in place.
Posted by: 914werke Aug 30 2022, 10:19 AM
I have been looking at options for this as well..... 1) I thought the CSP set up was perfect (not cheap). They have two on their site - one for a type 4 Beatle and one for a type 4 Bus. I contacted them and they said neither works for a 914
Ya nope. Ive installed the vers for the T4 on several cars & sold a dozen more.
They are my go to ... for carbs
Posted by: simonjb Aug 30 2022, 11:20 AM
Thanks very much..
Do you know which one you get? Some folks have said won't work because of the carb offset?
On any case, If you have done it I am sure it will work!
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