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? |
Eric_Shea |
Nov 4 2013, 10:02 AM
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#2
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PMB Performance Group: Admin Posts: 19,278 Joined: 3-September 03 From: Salt Lake City, UT Member No.: 1,110 Region Association: Rocky Mountains |
QUOTE If you are and you floor it on your test drive you're stretching and "unadjusting" the linkage. (IMG:style_emoticons/default/agree.gif) Have a friend watch the throttle plates as you press the accelerator. Then move the throttle stop under your pedal to accommodate. The linkage is mechanical. If there are no worn parts it will work if adjusted properly. If adjusted once and then it becomes "un-adjusted" something is at play. * Adjust the valves * Set the timing properly (error on the advanced side) * Fuel pressure must be at 3.5 PSI * Carbs should be sync'd and tuned with the linkage "off" * Follow procedures for the idle screw. Not having the engine timed properly can lead to an exaggerated idle setting just to get it to idle and carbs that wander into the progression circuit. * Drop links should be set at equal lengths. (two 8mm bolts in a vise) * Linkage mounts should be adjusted to accommodate the equal length length drop links. * Cable should be adjusted to stop when the plates are at WOT. Some of this may only apply to the IDA3C type carbs (linkage mount adjustment) but, what is hopefully emerging is a pattern of "everything" has to be right in order to tune a carb properly. |
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