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Reply to "High altitude move - stumbling"

As someone mentioned further up this thread, if the carbs were tuned on the very rich side at sea level, they could start bogging at 3500 ft. Only way to know is to adjust them or put a wideband O2 meter on it. Right?

You or I would know a lot by pulling a plug or two as well, but I think we're sticking Mark's head under the business end of a firehose here, and expecting him to come up refreshed and ready to roll.

The thing we're asking him to do has frustrated every single one of us, to the point that some of us have of wished the earth would open up and swallow the stupid car and put us out of our misery. Guys sell their cars with <500 mi. on them with some "no garage room" excuse or another when we all know it was the dreaded idle jet

... or maybe the ignition pickup module loosened up. Or maybe the manifolds are falling off and the whole thing is sucking large gobs of air downstream of the carbs themselves. Or maybe the entire main-jet stack backed out and is laying beside a velocity stack. Or maybe a plug wire is burnt and making poor contact.

The possibilities are endless. Every single one of them has happened to me.

Regardless, we're asking that he do this right out of the chute and without the background, tools, or spares which would ensure that he was able to get those carbs apart and back together again without a brass thingie moment. We're offering support as we sit in our offices or dens or kitchens 1000 miles away, throwing out best guesses (which almost never get to the root of the actual issue). I'm waiting for somebody to suggest the stupid Tomlinson manual. If Mark had wasted his time and money on all of this back in high-school, he would have ensured that he was inadequately compensated for the rest of his life - but he also would be equipped and outfitted to do what we are asking.

Even if one has the knowledge, tools, and background - something as uncontrollable as one's physiology often plays into this. I've been told I've got "Chevy hands". I struggle to find gloves that will fit over my paws, and I tend to break things trying to get them just tight enough. Pulling jets on Weber carbs in a pan-based replica engine bay requires hands the size of a small child's, but with the strength of a pipefitter's - and the delicate touch of a mother with her newborn. It requires almost contortionist levels of dexterity and being deeply, madly, and passionately in rut with your car just to get at the front jet. The back ones require some sort of deal with the devil or taking a sawzall to the inner fenders of your car. These are skills useful in almost no other endeavor in life  - not even with other cars.

It's madness.

Calgary is a big city with a lot of loose money floating around. Surely there's somebody with the tools and the shop to diagnose and repair the car without treating it like some freak-show oddity. Even better would be an aircooled club that populated by at least a few guys who work on their own stuff. I'll bet Mark could have his car running well in an hour if there was somebody to help walk him through it.

As it stands with our interweb troubleshootin', I'm not so sure we're even aiming at the right thing here. He says it idles fine - it struggles under load. Perhaps we're chasing the red herring because it was suggested to him that maybe he would need to rejet. If it's load related, I'd look hard at ignition before I dove into the black heart of darkness. 95% of all carburation issues are ignition.

Either way, I'm tapping out. I'll be anxiously monitoring this thread for a resolution. Good luck, Mark.

Last edited by Stan Galat