Weber IDF Main jet help |
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Weber IDF Main jet help |
tornik550 |
Aug 11 2010, 07:29 PM
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#1
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Senior Member Group: Members Posts: 1,248 Joined: 29-January 07 From: Ohio Member No.: 7,486 Region Association: None |
I am in the process of tuning my car after a rebuild. I have dual weber 40's. My engine is a 2.27L. Everything is going pretty well. I am slowly getting the jetting closer and closer. I was driving around at about 60mph yesterday. The head were hotter than I like (325 degrees). I checked the spark plugs and they were bone white. The main jets were at 160. I increased them to 170 (above 160 I only have increments of 10). With the increase to 170, the car is running very well and the temp at around 60mph cruising is around 275. I sped home, tuned off the car and took out the plugs- bone white. I was quite surprised.
The main jet size sounds high too me. Does it sound high to everyone else? Is it possible that I am needing a high main jet size because of the float level? I have my floats set at 10.5 with the gasket. Any opinions would be greatly appreciated |
tornik550 |
Aug 13 2010, 06:30 PM
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#2
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Senior Member Group: Members Posts: 1,248 Joined: 29-January 07 From: Ohio Member No.: 7,486 Region Association: None |
I am new to carbs. I am a human mechanic and not a car mechanic. I am trying to learn and I appreciate everyones help.
Last night I only made three changes. The changes were that I increased the venturi size which should have leaned the mixture. I slightly increased the fuel pressure and I raised the float level from 11mm with the gasket to 10mm with the gasket. I then had a super rich mixture. Today, I drove around quite a bit and played with the mains. I had AC jets of 190 the entire time. I tried 180, 170 and 160 and all were rich however 160 didn't seem too bad. I didn't have a 155 with me so I tried 150 and Now the mixture is lean. I am trying to find my 155's and i think that I should be dead on. |
ME733 |
Aug 14 2010, 04:48 PM
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#3
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Senior Member Group: Members Posts: 842 Joined: 25-June 08 From: Atlanta Ga. Member No.: 9,209 Region Association: South East States |
I am new to carbs. I am a human mechanic and not a car mechanic. I am trying to learn and I appreciate everyones help. Last night I only made three changes. The changes were that I increased the venturi size which should have leaned the mixture. I slightly increased the fuel pressure and I raised the float level from 11mm with the gasket to 10mm with the gasket. I then had a super rich mixture. Today, I drove around quite a bit and played with the mains. I had AC jets of 190 the entire time. I tried 180, 170 and 160 and all were rich however 160 didn't seem too bad. I didn't have a 155 with me so I tried 150 and Now the mixture is lean. I am trying to find my 155's and i think that I should be dead on. ...................terriffic......your jetting is in the range I suspected it might need to be in...., continue to keep an eye on the OIL temperature and Cylinder Head Temperature. Try a little longer trip after you get the 155,s in and see how it goes....Murray. |
jeffdon |
Aug 14 2010, 09:02 PM
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#4
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Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
This is some of the most insightful carb tuning talk i have seen. And I am just getting started on optimizing my set-up, so its damn timely info.
Keep it coming. |
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