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 |
McMark |
Aug 13 2010, 02:19 PM
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#2
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
The rate at which fuel is admitted to the emulsion chamber is controlled by the main jet, not the fuel bowl level. The float height has nothing to do with that. To get nitty-gritty about it, a higher fuel level in the wells (due to a higher float setting) will provide a SLIGHTLY richer mixture just as the main jets come into play. But soon after that the emulsion tube situation stabilizes and you simply have fuel flowing at the rate allowed by the main jet and air flowing at the rate allowed by the AC jet and E-Tube.
You can't seriously be arguing that the level of the fuel being pushed by atmospheric pressure from the fuel bowl, is GREATER than the vacuum influence from the chokes? (IMG:style_emoticons/default/blink.gif) |
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