Carburetor jetting, Recommended base line jets for Weber 40s |
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Carburetor jetting, Recommended base line jets for Weber 40s |
Slanski62 |
Jan 10 2017, 11:14 PM
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#1
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Newbie Group: Members Posts: 2 Joined: 22-October 16 From: Chapel Hill, NC Member No.: 20,520 Region Association: South East States |
Hello. I'm new to the forums here but have been reading and learning a lot. Thank you.
I have a pair of Weber 40s I plan to use on a 2056 I'm building. The carbs are used, and I don't know how they're jetted. Can anyone recommend a base line? I'm at an altitude of 486 feet. I appreciate any suggestions! Steve |
jmill |
Jan 13 2017, 04:40 PM
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#2
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
You'll know if it has ethanol in it. There'll be a sticker on the pump that says something like "up to 10% Ethanol added".
Carb pops are usually caused by a lean condition. That means vacuum leak, clogged jets or jets too small. They can even be caused by an improper linkage or bad linkage setup (not synced). Assuming you have mixture screws properly adjusted 1- check for vacuum leaks 2- check out linkage 3- clean idle jets 4- step up idle jets (as said, 47's are on the small side) Exhaust pops have a few causes. Again assuming mixture screws properly adjusted 1- check for exhaust leaks 2- adjust valves 3- idle jet too small |
amfab |
Jan 13 2017, 06:28 PM
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#3
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Member Group: Members Posts: 393 Joined: 17-May 16 From: Los Angeles Member No.: 20,004 Region Association: None |
Great! Sorry for the thread hijack, I saw this thread and had to ask.
You guys gave me great notes on this. As soon as I finish my longs and floorpans and the car is back on the ground Ill get on this. In the meantime Ill order some bigger jets so I'm ready to go, maybe just replace the gaskets while I'm at it. Carbs were synced and idles set when I had it tuned up and valves adjusted a few months ago. It runs pretty well aside from the popping, i have experienced partially clogged jets before and its not that bad. Is there a best place to order jets? |
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