I first let this out to the CS Registry 8 years ago, figure some since-then-newbies may benefit and may not have heard of this...
After decades of "the possibility" that our car may have been overheated, it is pretty likely that overheating has occured, perhaps more than once or twice. Often, even the original heads simply get shaved (!) to take any heat-induced warpage out of them...but can YOU recall someone mentioning warping in the zenith carb assemblies?
I'd wager not often. The next time you have time on your hands and decide to maybe re-build your zenith carbs, try lapping the bodies mating surfaces on a piece of flat plate glass with rouge ... First, you will be amazed at how the first few passes betray some significant out-of-flat condition. Next, continue to patiently lap the surfaces ONLY until you get a consistent polish/finish/shine on the entire flat face surface. Do NOT over-do it. More is NOT better, you only want "just enough." Then, if you have done everything correctly on the rebuild/re-assembly of your carbs (itself a challenge for far more of us than would care to admit) you will find yourself with a pair of carbs, when synched properly, that are very responsive and perform very well across the whole powerband range AND last a lot longer than the cha-ching "non-FIA-approved" Webers and even hold a tune!
So there! I finally said it. If you decide to repeat this in print, please make a (fair) attribution, I'm not making this up.
After decades of "the possibility" that our car may have been overheated, it is pretty likely that overheating has occured, perhaps more than once or twice. Often, even the original heads simply get shaved (!) to take any heat-induced warpage out of them...but can YOU recall someone mentioning warping in the zenith carb assemblies?
I'd wager not often. The next time you have time on your hands and decide to maybe re-build your zenith carbs, try lapping the bodies mating surfaces on a piece of flat plate glass with rouge ... First, you will be amazed at how the first few passes betray some significant out-of-flat condition. Next, continue to patiently lap the surfaces ONLY until you get a consistent polish/finish/shine on the entire flat face surface. Do NOT over-do it. More is NOT better, you only want "just enough." Then, if you have done everything correctly on the rebuild/re-assembly of your carbs (itself a challenge for far more of us than would care to admit) you will find yourself with a pair of carbs, when synched properly, that are very responsive and perform very well across the whole powerband range AND last a lot longer than the cha-ching "non-FIA-approved" Webers and even hold a tune!
So there! I finally said it. If you decide to repeat this in print, please make a (fair) attribution, I'm not making this up.
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