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Discussion Starter · #1 ·
air filter adapter

Has anyone tested/flowed the TWM remote air filter adapter for our downdraft carbs?

-Travis
 

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I've got a deal for you. You buy it, I'll test it AND flow it.:D :D

Bob
 

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Discussion Starter · #3 ·
Is your flow bench set up? If you're serious I'll get it on order tomorrow...

-Travis
 

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I have a 32/36 adapter to round air filter

made by K&N


and Marty bought the round snorkel made buy K&N to go on top of his DGAS

it looks a lot like the stock snorkel thing

Davegt74
 

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Travis said:
Is your flow bench set up? If you're serious I'll get it on order tomorrow...

-Travis
No, my flow bench is still in storage in my barn, haven't used it in almost 3 years. I was merely being a wise-ass (again).

Bob
 

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Discussion Starter · #6 ·
Dave

I don't find the snorkel on their web site. Do you have a part number or know what they call it?

-Travis
 

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It's possible they don't even make it anymore. I told Marty about it MANY years ago and he bought a setup, I remember in two year's time after that the price nearly tripled, I think maybe they were trying to get rid of old stock?

Anyway, there was a carb base adapter which bolts to the Weber and has a 'tower' above the carb to accept a screw, then the cast aluminum carb 'hood' which screws onto the adapter, then the option of attaching a cone style filter directly to the hood or making a remote air pickup with some air duct hose (better option IMO).

BTW, the K & N carb hood very closely emulates the stock GT carburetor hood, except it's cast aluminum with fins on top (simulates valve cover nicely), and the plenum area is much larger and therefore less restrictive. The base of the carb adapter has the typical round Holley dimensions, so a round Holley air filter could be used instead of the carb hood.

Bob
 

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i was up on TWM's web site and that's the same stuff K&N use to sell

so either TWM used to make it for K&N or TWM bought the molds

I bought my adapter from Supeshops

a few small problems where
1) you could not use a base for the air cleaner
that would lift the air cleaner up to high

2) there was a little interference with the passenger side hood latch


also Bob hit the nail on the head, you could use the finned snorkel with the stock air cleaner set up

And put a K&N in the stock canister.

the cost was around $95 back in the day

one small problem with snorkel

it is shorter then the stock snorkel so it might not flow that well
i always wondered about that

i will try to take a PIC of the round adapter

Davegt74
 

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Something I've always wanted to make but never had time to try was an integral airhorn/carb adapter setup for a Weber carb. One of the Formula Ford race engine builders has an airhorn setup that gains 2-3 hp from a 2000 cc FF with 32/36 Weber. But it's $280 for the airhorn!!

I thought about making a composite airhorn that also has the hood similar to a stock GT's, so you could run a remote filter with a piece of flexible duct, and gain the benefits of cooler air and the better air entry radius from the airhorn. On the Webers I've ported/flowed, the airhorn mods I've done have always added a noticeable amount of airflow. Making the molds would be a bit of work however, which is why I never went any further than brainstorming.

Bob
 

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Discussion Starter · #10 ·
TWM makes one which is 2" tall. I suspect it's the one Pegasus is selling for $246. There is a note that there is no provision for a choke assembly. Maybe it has to be cut off?

Something to this affect has been on my FUTURE todo list for a while. I had considered a radiused plate which sits on the top of the choke tower. I had also considered copying the TWM part by siameseing two standard air horns...this could also be the basis for a mold.

So Bob, you must have known that one of us would ask about your airhorn mods. Care to elaborate? pics?

BTW, Jam engineering is getting $62 for the snorkel.

-Travis
 

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Travis said:
So Bob, you must have known that one of us would ask about your airhorn mods. Care to elaborate? pics?

-Travis
I have no pics of the mods currently. I *do* have one modified DGAS carburetor in pieces, it has the venturis bored out to 30.1 mm (from 27mm stock), the auxiliary venturis streamlined and thinned out, the throttle plate screws and throttle shaft trimmed down, the choke tower radiused and polished, etc. I have another one I did on a friend's car with 2.0 block/1.5 head, and in fact that engine will be coming out soon to be replaced with a 2.2 litre, so that carb may be available for inspection soon. I had another one of these modded 38 DGAS's on my old Ascona, it really ran well. Needs higher compression to use it on the street, the larger venturis would hurt vacuum too much on a low compression street engine....mine had 11.02:1 compression...it pulled nicely from 2500-7000 rpms. I forget the actual flow numbers, but I seem to recall all the mods improving flow by *about* 60 cfm over the DGAS's stock 330 cfm.

If you see me again this year Travis, remind me and I'll bring the carburetor body along to show the changes I made. I think I had to drill the pump squirters out a few thou too, to around .026". And that engine had enough cam, so that I needed to drill the throttle plates to bypass enough air so I could close the throttle plates and it would allow it to still run in the idle circuit (per your experience Travis).

Bob
 

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Discussion Starter · #12 ·
I'll likely see you on Sunday. Is there a web site with times and directions?

-Travis
 

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I think this link will tell you what you need to know.
http://www.rallyracingnews.com/scca/pr4-NERRallyXSeries02.html
I'm leaving for Vermont Thursday night, then Friday I have to thrash a bit and install the 4.67 rear axle, and the twin master cylinder pedal box, plus some new brake lines. Still need to break in the rear axle, and figure the brake bias before the rallycross on Sunday.

I'll try to remember to bring the carburetor. Definitely bringing the camera to get some pics. Tom Drake lives nearby, so he said he *may* show up to spectate, or perhaps even run my friend's Ascona in the rallycross, we're allowed up to 3 drivers per car.

Bob
 

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Are the adapters you are talking about the same as the ones that Jam Engineering has? They show both single and double snorkel models for $52. http://www.jameng.com/products/index.phtml?section=6. Does anyone know if they will fit under the GT hood? If so, I think it's time for me to build a cold air intake the easy way!
James
 

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Discussion Starter · #16 ·
N61WP said:
Are the adapters you are talking about the same as the ones that Jam Engineering has? They show both single and double snorkel models for $52. [/B][/QUOTE] $62. Yes, this is the one -Travis
 

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Discussion Starter · #17 ·
TGSI Racing said:
Travis,

I'll duplicate Bob's offer. If you buy it, I'll flow it... and my flow bench is set up.

Bob... the other Bob
That would be great. I'll let you know when it comes in

-Travis
 

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Okay, I've finally finished it. I bought the Jam engineering adapter. As someone said, it's fined aluminum, matches the valve cover and looks great. I got the one with the single oval intake, 2-1/2"x2". I don't know how to calculate flow area for an oval, but I'm speculating that it will flow enough for a 4 banger. I then found a 2" rubber plumbing coupler from Home Depot that fit the oval good with a clamp. I bought 3" air intake flex hose, a 3"OD x 5" piece of exhaust pipe that fits through the factory hole. I bought a K & N type cone filter that fits in front, and it wedged in so well that I didn't even need to build a bracket to support it. I had planned to order a K & N universal filter, but found this one at Auto-Zone and didn't want to wait. I guess it is for the Rice Boys, but it's way large so even if it doesn't flow as well as the K & N, it's still over kill. The front of it is also a concave air inlet. It has a 3" opening so it fits on the exhaust pipe nipple perfectly. I'm gonna try to attach a pic....sorry 3 tries..I'm out
James.
 
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