I hate my Carbs Much Less, Chris Foley is a God! |
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I hate my Carbs Much Less, Chris Foley is a God! |
Mblizzard |
Oct 30 2013, 12:13 PM
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#1
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
Well after much playing and changing I have to say I hate my carbs. I have done every jet size and I can't really get it to run well on anything but 70 idle jets and that is way to rich. With 60s it runs not quite as rich but the hesitation on the initial throttle is huge.
Have played with the adjustments and I think I have it running well but it never performs well. 2056 just built, 44 IDFs, 60 idle jets, 28 vents, 135 mains, F-11 emulsion tubs, 175 air correction jets. Timing at 27 to 30. SVDA Dizzy with electronic ignition. Valves recent set and rechecked. Synced at idle and 1500 rpm. Runs well at higher rev and pulls strong but I can't get rid of that hesitation. I know there will always be some but at times from a dead stop it almost stalls. What am I missing? (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/headbang.gif) Gone through all of the Weber tech trouble shooting steps and I can't find anything that says I have something wrong. Is there an adjustment on the accelerator pump? Or do I need to up the accelerator jet? I will be going back to FI at some point but these carbs should work better than they do. Taking it to Eurohaus tomorrow maybe they will have better luck. Suggestions? |
ThePaintedMan |
Oct 31 2013, 07:29 AM
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#2
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Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States |
Thanks for the props Mike, but it was really Rich, the Cap'n, Bill and others who are giving you the right suggestions. (IMG:style_emoticons/default/beerchug.gif)
It's possible that it's the timing that's throwing you off, but it's probably a few things compounding here to cause the issues. That initial shot of advance makes a big difference, but so do the others that were mentioned. In theory, 44s can be choked down with the right venturis, but as Rich mentioned, they really are designed for bigger motors and that's a lot of space underneath the venturi that adds a big variable. Not to mention that the stock FI cam, as many have said, doesn't produce the right vacuum signal at low RPMs to make carbs work the way they should. Obviously, the car will run, but not at it's full potential. I also agree with the wideband O2 sensor install. Again, I'm a hypocrite as I never got a chance to put one in my car, but at some point I will. It really will take the guesswork out of the jetting at least, and then you'd be able to move back to fine-tuning the other parameters. Sounds like you're on the right track though. Let us know what type of linkage you have, and what the results of the synchrometer are at idle, 2,000 and 3,000 rpms, just out of curiosity. |
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