I am looking in to running a single Weber downdraft on a Chevy 292 inline 6 to replace the worn out Rochester B. I would be replacing the stock Chevy intake, and running Langdon cast split exhaust. I was informed by Tom Langdon that when doing so I would need to run coolant through the intake to replace the stock exhaust heat system. My question is, I know this is a somewhat common issue with the Rochester Bs, but, are the Weber downdrafts as prone to freezing up? I'm wondering if I'll need to make and plumb a coolant plate to keep the Weber from freezing up. I have seen numerous downdrafts used on hoodless rigs with little to no heating provided, but, I would wager most of those vehicles don't get driven as much, or, in the cold conditions that this engine will be seeing. It will be in a 64 C10. The model I'm interested in running is the 44 IDF or something very similar.
had a 48 on a built vw & had to let the motor warm up good in the winter - it would ice up around the throats & start spewing black smoke out the exhaust (rich) if it wasn't warmed 1st
I put a Weber two barrel (Pinto replacement style) on my girlfriends Honda back in the late 70's along with a set of home made tubular headers and it had an icing problem in cool weather. Running about 80 up the highway early one morning I lifted off the gas as we came up on a slow moving truck and the car just kept going at the same speed. Pushed in the clutch and shut the motor off and when we coasted to a stop and pulled the air cleaner the carb was frozen up. I ended up putting a heat stove off the header to fix the problem. Roo
ive never had my weber freeze . when we ran the on motor cycles they did alot . mine is not in contact with the exhaust (header) . i wonder if that is why mine runs so rich ?? .... steve
Never had any problems with lots of them over the years on VWs, but I always have lived and drove them here in Phoenix. Not exactly them most freeze prone part of the country!
Every carburetor will freeze up especially in cool damp weather (just above freezing). The evaporating gas acts like a refrigerator. Put some alcohol on your hand and blow it dry, see how it cools. You can combat this by making an air filter that picks up warm air from the exhaust manifold or by heating the intake manifold. Stock carbureted cars had both these features, they really help.