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Weber snorkel kit

17652 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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Lookee . . . lookee . . .

opelenvy said:
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.
. . .

Ready to run my Hooters GT yet? Just kidding. You have NOTHING to prove to me! :D
opelenvy said:
Yes, I did try it out, the stock bellow is quite a bit bigger, maybe 3.5" or more.

. . . 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.

Air and all these jets . . .

opelenvy said:
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'....
Sorry to hear that snorkel was the culprit though I'm glad you found the cause and were not too proud to share it here. Had wondered more than once why others that used the same jets had good results and you still had that stumble. Like you said though, tuning takes time AND perseverance!
Stock snorkel and weber adapter mods on 32/36

GTJIM said:
The "J Edgar Opel" article, in the Tech files, about warming up a 1970 GT mentions that the stock snorkel set-up gave 2 HP better than the other things tried. Guess Stutgart Universty got to play with the air flow trough that too - as well as the aerodynamics of the body! ;)
Guess my approach wasn't too far off the mark after all! Look at the "K&N Filter for 32/36" thread for the stock snorkel adapter mods I made. Ted in San Antonio is running my carb (his now) with this cold air setup using stock parts and K&N filter. Hasn't had any problems with it even running A/C. I digress.
Redesign Suggestion for JAM

opelenvy said:
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.
George, et al,
Quick fix looks good but, by looking at the middle picture, you could suggest that JAM cast your spacer integral with the bottom adapter and cast the center stud bracket mounting risers taller at the same time. Eliminates pieces, ensures proper fit and simplifies installation.

Kit would then include: bottom adapter with integral lip and taller risers, top snorkel half, center stud snorkel mount bracket, 4 carb adapter mounting screws, 2 center stud bracket mounting screws and 1 acorn snorkel mounting nut.

That said, I'm more than a little surprised that JAM didn't discover this serious air restriction when they originally designed this snorkel. Obviously NEVER tested! :mad:
Not again . . .

opelenvy said:
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.
Says it all now, doesn't it! :(
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