Author Topic: New cold air intake design  (Read 8579 times)

September 01, 2010, 12:15:49 pm

overdrivegear

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New cold air intake design
« on: September 01, 2010, 12:15:49 pm »






New cold air intake for my cabriolet diesel.  Made with a special rubber flex hose with smooth inner and vacuum attachment at the bottom.  Makes the car run very smoothly at 60 mph with much less emission when I hit the throttle.  Definitely delivers a cold air charge and perhaps helps out a bit with volumetric efficiency, fresh air scavenging, etc.  Obviously there really isn't any serious performance gain, but it seems to run cleaner this way. 

Clearly if I drive through a pond of water 18" deep, I'm screwed but then again, I don't plan on doing any jungle cruising.  The attachment brackets are medium gauge sheet metal so if I forget it's there and pull up too close to a parking barrier, it will simply flex the brackets back and not bend my valance.   


1985 Westy Golf 1.6 NA
1987 Cabriolet (soon to be 1.6 NA)

Reply #1September 01, 2010, 12:23:43 pm

GEE-BEE

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Re: New cold air intake design
« Reply #1 on: September 01, 2010, 12:23:43 pm »
I wondered what happened to my vacuum nozzle ?

here are some other idea's

aircraftspruce.com

cat duct 2' :05-29808
flange 2'     10350-8
other sizes available

Drill a hole, pop rivet the flange, connect to intake inlet
You can also add another flange and connect to a hole in a airbox assy
This is what Iam installing, this would be a std type of install on aircraft
Gee-Bee
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Reply #2September 01, 2010, 12:43:19 pm

Vincent Waldon

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Re: New cold air intake design
« Reply #2 on: September 01, 2010, 12:43:19 pm »
Very clean install!!!  My 81 caddy always felt a bit quicker on the highway with my shop-vac intake... nowhere near as well done as yours tho.

Since this is the internet... someone's gotta state the obvious caution: at 23:1 compression the combustion chamber volume of a 1.6l diesel is 16.7cc or a little over 1.2 tablespoons.  Deep puddles aside, any more rain or splashing than that in a single gulp and a rod is going to get bent.  Obviously it's gotta get past the air filter etc and be ingested all in one swallow... but 1.2 tablespoons is not a lot of water, either.

1.2 tablespoons... just something to be aware of on cloudy days!
« Last Edit: September 01, 2010, 12:45:01 pm by Vincent Waldon »
Vince

Edmonton, Alberta, Canada
2001 silver TDI Jetta Malone Stage 1.5 , 2001 blue TDI Jetta SBIII 216s Malone Stage 3, 1970 Bay Window bus

Gone but not forgotten: 1969/1971 Beetles, 1969/1974 Westies, 1979 Rabbit, 1986 TD Jetta, 1992 gas Jetta, 1994 TD Jetta

Reply #3September 01, 2010, 12:57:48 pm

GEE-BEE

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Re: New cold air intake design
« Reply #3 on: September 01, 2010, 12:57:48 pm »
I think a 2' hole and flange next to the headlight would be cleaner and safer, air would be a direct shot also
cat tubing  can be purchased in any size along with the flanges.

GB
1.9 AAZ, CHD 5spd with Peloquin
KO4/KO3 Hybrid turbo
Giles Pump OHC
Complete Techtonics 2'5 S/S DP and Exhaust
Coilovers, MKII Pedal Swap,G60 BRAKES
MK1 JETTA DASH
675MM 16V radiator (MKII) PASSAT DUAL FAN
42K original miles , South African Front End
15x6 Le Casletts 195-45-15

Reply #4September 01, 2010, 02:31:27 pm

Vangruver

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Re: New cold air intake design
« Reply #4 on: September 01, 2010, 02:31:27 pm »


i like that idea! but might I suggest that you install a bypass valve such as the one shown above?

while the CAI is a great upgrade for almost every car, it still has a potential to take in moisture whilst driving. The bypass valve will trap all moisture into the lower portion letting it drain prior to the air going into the intake.

Reply #5September 01, 2010, 03:19:48 pm

madmedix

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Re: New cold air intake design
« Reply #5 on: September 01, 2010, 03:19:48 pm »
After looking at the bypass valve on their website: it occured to me that maybe using a section of rubber intake, cut in half, then a section of open-cell foam rubber-cemented to it would work well (the kind of foam sheet that electronics is packed in)...or...how about using some wrapped around the intake at a bend at the lowest point and secured with dryer clamps on both ends..there would be some air loss but water sucked in that scoop would blow out the foam curve instead of climbing up the intake?

'90 TD Jetta

Reply #6September 01, 2010, 08:20:45 pm

vanbcguy

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Re: New cold air intake design
« Reply #6 on: September 01, 2010, 08:20:45 pm »
Very clean install!!!  My 81 caddy always felt a bit quicker on the highway with my shop-vac intake... nowhere near as well done as yours tho.

Since this is the internet... someone's gotta state the obvious caution: at 23:1 compression the combustion chamber volume of a 1.6l diesel is 16.7cc or a little over 1.2 tablespoons.  Deep puddles aside, any more rain or splashing than that in a single gulp and a rod is going to get bent.  Obviously it's gotta get past the air filter etc and be ingested all in one swallow... but 1.2 tablespoons is not a lot of water, either.

1.2 tablespoons... just something to be aware of on cloudy days!

At 2400 RPM though that's 24 tablespoons per second... Immerse that sucker and yeah, you have problems but in reality it'd take quite a bit of water to actually get that much flowing all the way up the intake.  DEFINITELY not something for a car driving on gravel roads with lots of deep puddles though!
Bryn

1994 Jetta - AHU M-TDI - Jezebel Jetta
2004 Jetta Wagon - 1.8T - Blitzen

Reply #7September 02, 2010, 09:04:53 am

gldgti

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Re: New cold air intake design
« Reply #7 on: September 02, 2010, 09:04:53 am »
air filter makes a good misting device.

I have had a 3.5" PVC intake on my n/a diesels for a long time. I did once plumb it down to the area shown by the OP but found on hot australian summer days it did more harm than good, with superheated air from the road coming in.

i have found the best compromise to be just behind the grill next to the radiator, and as an added bonus it makes it fun when changing the air filter to count the insects :-)
'77 Golf LS 4 door twincharger project
'91 Golf Cabrio 1.9TD
'94 Golf TD - AAZ, 2.5" Mandrel DP and exhaust, Merc T3 1.6TD boost pin, FMIC, Koni suspension, VR6 Brakes, VR6 Seats, VR6 sway-bars - sadly missed
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Reply #8September 03, 2010, 07:30:41 pm

Dirtrag2

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Re: New cold air intake design
« Reply #8 on: September 03, 2010, 07:30:41 pm »

At 2400 RPM though that's 24 tablespoons per second... Immerse that sucker and yeah, you have problems but in reality it'd take quite a bit of water to actually get that much flowing all the way up the intake.  DEFINITELY not something for a car driving on gravel roads with lots of deep puddles though!

can't be much worse than running water/meth injection... hmmm I wonder... anyone ever figure out a safe water injection flow rate on idi's  ???
...Darcy
'97 Jetta 1.9TD ( dirtrag2 )
'88 Fox Wagon ( projekt Dirtrag 3 )

Reply #9September 05, 2010, 10:21:43 am

UAofE

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Re: New cold air intake design
« Reply #9 on: September 05, 2010, 10:21:43 am »
Thats a very nice water scoop.

Reply #10September 05, 2010, 11:38:41 am

theman53

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Re: New cold air intake design
« Reply #10 on: September 05, 2010, 11:38:41 am »
I had mine on the passenger side. I think yours will be fine as it seems where I am from most of the big holes are on the passenger side. Plus you have to over come gravity to get it all the way up there and water is a lot heavier than air. Unless it is a fine mist of water and then it shouldn't hurt you :D

Reply #11September 05, 2010, 11:45:16 am

R.O.R-2.0

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Re: New cold air intake design
« Reply #11 on: September 05, 2010, 11:45:16 am »
i would have gone with ALOT BIGGER tubing from the front to the air box. think of how bad the stock snorkel flows? well now take and make it 4 times as long.. yea... its gonna really have sub-standard flow. is the gain from the cool air enough to counter-act the tiny intake tubing? and ive also heard it causes excess turbulence using that hose with a spring in the core.. kinda like using dryer hose for an intake.

and you could have taken and mounted your vacuum cleaner behind one of the little mini-grilles under the bumper.. then it would have been totally hidden  ;)
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #12September 05, 2010, 06:02:12 pm

GEE-BEE

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Re: New cold air intake design
« Reply #12 on: September 05, 2010, 06:02:12 pm »
On that note : I would use a 1Y intake and go from there

GB
1.9 AAZ, CHD 5spd with Peloquin
KO4/KO3 Hybrid turbo
Giles Pump OHC
Complete Techtonics 2'5 S/S DP and Exhaust
Coilovers, MKII Pedal Swap,G60 BRAKES
MK1 JETTA DASH
675MM 16V radiator (MKII) PASSAT DUAL FAN
42K original miles , South African Front End
15x6 Le Casletts 195-45-15

Reply #13September 06, 2010, 12:48:31 pm

R.O.R-2.0

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Re: New cold air intake design
« Reply #13 on: September 06, 2010, 12:48:31 pm »
not everyone can afford expensive intake manifolds.
and on a 1.6, a gasser intake would be better, because it actually has the right intake ports. and gasser manifolds are WAY cheaper, and work just as good.
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #14September 06, 2010, 02:52:58 pm

GEE-BEE

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Re: New cold air intake design
« Reply #14 on: September 06, 2010, 02:52:58 pm »
I have a 1Y sitting and the stock snorkel tube in a box for 150.00

I did have it professionally cleaned

I havent seen a 1Y filter assy thou..

GB
1.9 AAZ, CHD 5spd with Peloquin
KO4/KO3 Hybrid turbo
Giles Pump OHC
Complete Techtonics 2'5 S/S DP and Exhaust
Coilovers, MKII Pedal Swap,G60 BRAKES
MK1 JETTA DASH
675MM 16V radiator (MKII) PASSAT DUAL FAN
42K original miles , South African Front End
15x6 Le Casletts 195-45-15