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Weber snorkel kit

17653 Views 78 Replies 24 Participants Last post by  opelenvy
air filter adapter

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

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ben said:
what did it cost too build and can make one for me
with steel
I have finished mine with the same Weber adapter and the same filter. But I used steel 2.5" mandrel bent pipe painted with high heat paint. (polished aluminum color for the rice boys)
Used 2.5" rubber boots made for 2" ID PVC, so they measure 2.5".
Might I ad that the rubber boot going through the radiator wall is nice and snug. No rubbing, rattling, or supports needed.
I had to put a one of the boots on the end because the filter has a 3" ID hole. I will order a K&N that fits on the 2.5" pipe and then I can take that off. Though I may leave it on as a support since it fit's so well.


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Look in my photo's, it was a prebent "J" pipe, 180 degree bend. I got it locally, but JCW does sell them. I didn't take any measurements before I put it together, and I REALLY don't want to take it back apart.:eek:
from the pictures you can get a really good idea. I only used two pieces


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kwilford said:
I wondered if the throat would fit the stock air cleaner bellows. Did you happen to try that before you fabricated the pipe?
Yes, I did try it out, the stock bellow is quite a bit bigger, maybe 3.5" or more.

And I have no way of verifying how well it breaths aside from running it.
Can anyone tell me if this is messed up logic. I have a 2" exhaust pipe going out the back, so the 2"x2.5" oval on the adapter is still larger than the exhaust. I know there are other factors, but I figured it can only take in as much air as it can put out at the same time. So the 2x2.5" oval being the most restrictive part of the intake will be no problem.
The walls of the opening are pretty thick as well and I plan on using my handy dandy die grinder and opening it up as much as I safely can. Every little big will help. (I don't know what you are talking about. Is that a Freudian slip?):D
Bad news on the cold air intake.

Well the good news is I figured out what was causing the stumble when I kicked in the secondary, the bad news is it is my cold air intake setup. :mad:
I had tuned my carb. and had it running good with nothing on it. When I put on the intake assembally, I got the stumble with the secondary. So I removed the jam adapter, the stumble is gone. I put only the Jam adapter on without the pipe and filter and I still get the stumble. It does fine on the primary, but with the extra gas of the secondary it seems it's not getting enough air. Another guy had made a riser to make the adapter level with the top of the carb. and that might fix the problem. Or the problem may be the opening of the snorkel. I will do some testing and try to find out. I don't get a lot of time to work on my car right now, so it will take a while. The other snorkel kit listed in this thread may be a better candidate. I think it comes from Weber or JTOutfitters.com or something. I know a couple guys have used it. Oh well....back to the drawing boards. I'll post my results, though it will be a while. So don't go using my design just yet. :( I am going to try and contact Jam Engineering and see what they say. Stay 'tuned'....
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Yea, it was a real bummer after it looked so pretty. :D
I came up with a way that accomplishes the same as Chuck's, but, sorry Chuck, it was a lot easier. I went to a well drilling place and he found me a piece of PVC tha is the same diameter as the Jam housing (almost). I cut off a slice that is 3/4" thick and dremeled it a bit to fit. I got two longer bolts to raise up the bracket on the inside that the top screws to. The screws and nuts were $1.15, and the PVC was free. :D
I haven't had a chance to test it yet but the trip to North Texas tomorrow will be the test. If it fixes the problem I would like to replace the PVC with an aluminum spacer. Should be pretty cheap as it is just a 5 1/2" ID pipe. The results looking through the intake hole look just like Chucks, straight shot to the throat. Here is one picture I snapped real quick of the completed project. If it works tomorrow like I hope then I will show more details. I don't want to brag too much if it doesn't work. :eek:
The next thing I want to do to it is with a die grinder open up the intake of the Jam snorkel some. The material is very thick and can safely be opened up some.
Oh, and thanks for the offer, Chuck.
Oh, and yes, the hood closes. The close part is the back of the Jam adapter close to the fire wall. The sheet metal behind the hump in the hood is close. But it clears fine.


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Scott McDonald said:
Hey Opelenvy-

Did I see your yellow GT cruising down to Galveston a few weeks ago? I noticed there was a nice one going that way a few weekends back.
Nope, not me.
Ya, I've seen that in the pictures. That is not the place to worry about clearance, really, it is in the back of the adapter where it will hit first. My stud is adjustable and I can lower it flush with the nylon lock nut. But the flush look IS much prettier.
And the meet is Saturday, not tomorrow. I thought tomorrow was Saturday all day. :rolleyes:
So I have an extra day! I may get to test it before I leave.
Jam's input on it.

I contacted Jim at Jam Engineering. I explained the problem to him and the fix I had come up with and he said he could make a spacer out of aluminum. I tried to get this as a complimentary fix since the kit does cost $60, but no go. He is makeing me one for $25, which isn't bad. I told him after I got it and tried it out that I would let you all know how I liked it and he might get some more orders for it. I should be getting it in a few days and not sure when I can test it out.
Stay "tuned".....
It is made out of aluminum like the top and bottom. They are cast and this is going to be a piece of tube machined to fit so it will look smoother. I'll post some picitures of it when I get it.
I asked the guy at Jam Engineering if he would do it cheaper if I drummed up some more sales. I told him that I could probably come up with at least half a dozen other buyers. He said that he is doing it by hand one at a time so it wouldn't matter. He said that he should have in done in a couple days, so hopefully mine is already done. Once I get it and approve of the job THEN I will post how to contact him. I don't want to put the wagon before the cart if this thing ends up not fitting or something. I don't see any reason why it wouldn't work, he has the Weber adapter right there to fit it to. I really should have it this week and i will post when I do.
I got it.

Got the spacer today. He had to machine a lip to fit the edge snug. This caused interference with the two front allen bolts since the holes are so close to the edge. I used the supplied bolts that came with the kit from Jam. They came with two different sets of bolts because the manual choke carb uses 4mm and the others use 5mm I think. Anyway I belive I am using the ones with the bigger heads, so the smaller head might not even cause this interference. I called John at Jam and he said he would look into this issue with the next ones he makes. The fix would be to use smaller headed allen bolts, or file/grind out a small groove in the spacer. But this is only my problem as John will address this for future orders. The quality of the work is very good and I think a good fix for the problem. I will still need to grind off a small area on the hood to clear where the top of the adapter is rubbing. (shown in an earlier post.) I got mine a couple bucks cheaper since I am the Guinea pig. Future ones will be $25 (plus S/H which he charged me $6).
And now for the pictures.


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Oops forgot to say, call John at Jam Engineering in Monterey, CA at 1-800-JAM-CORP (1-800-526-2677)
This picture is how I raised up the hold-down for the top portion.
Thats all.


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Otto, this is a univeral application. The height would probably be an issue for other vehicles useing this adapter. If Opel was the only use then it would not justify a separate kit. He told me this was not designed for a high performace application, but more for the functionality of relocating the air intake. I would not recommend people go this route if you are just starting to make a cold air intake. I am just trying to make it work since I've already invested the $$.
If I could do it all over again, I would not have bought that adapter.
My Personal Opinion.
N61WP said:
What's a shame is that it's such a nice looking piece. With the ribs, it matches the valve cover and looks like it was made for the car.
Goes to show you, looks ain't everything! :p
That's what drew me in. I'm all for things looking nice, but in the end "go" is more important than "show".
Live and learn and teach...so others don't have to make the same mistakes.
GTJIM said:
The standard Opel set up is VERY hard to beat, especially when fitted with a K & N filter. obviously, Stutgart University had a bit to do with getting the flow inside there correct too! ;)
Stutgart is a long way from Central Texas and I don't think they took into account the sweltering heat we have down here a good part of the year. 120 degrees coming up off the pavement isn't common in Germany. If it was they would have put air conditioning in these cars. :D
They didn't design oil coolers into these cars either, but around here is will more than double the life of your engine. That said, I am not saying there is anything wrong with the stock setup (that was designed for the Solex). I just like to be different. :D I DO think the stock setup can improved upon, though currently I do not think that mine is better. A work in progress...well, that's everything about my car.
OK, finally got around to doing a little work on the needed areas. Now it will be another couple weeks before I can test it out. :rolleyes:
Oh well here are the pictures. I could probably still open up the intake opening some more, I just ran out of time to work on it.


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