47-55.1 Triple Side Draft Webers

[mr48chev]

Simpy put the manifold (more of a plate than manifold) you showed in post one is designed for each carb to feed one of the individual ports in the head that serve two cyliners each with no way to feed the end cylinders off the center carb hence you cannot run progressive linkage. On the other hand the early Corvette intake works off a common manifold that could be run progressive but may or may not work best when run progressive. That intake, carb and exhaust mainfold has a combined resale value that is higher than some guys have in their whole trucks but that value would be killed if the finish on the intake or exhaust was altered from original I've seen one polished six cylinder Corvette intake at a swap meet years ago that had a Corvette restorer throwing a fit as he would have paid a premium for it if it hadn't been all polished up.

There is plenty of info out there on tuning the Weber side drafts and there are some guys who are really good on them but who normally work on vintage exotic foreign sports cars. You may end up at Norwoods in Dallas before it is all said and done. Bob sold out a few years ago but I think the shop still works on Vintage Ferraris. They might be the link to someone who can tune those carbs. https://www.norwoodautoitalia.com/

I've got a 68 292 for mine going with an Aussie Speed 4 barrel intake and the cast headers that Tom Langdon used to sell (I bought them from him) but 12 Bolt Tom Lowe sells now. I haven't picked a cam or carb yet though.