Ready to quit on Edelbrock 1406 carb swap, 5 installations and always leaks a lot

Thanks to Tony, Russ, Jason and Michael for detailed assist on this. Yes, Jason, I read your carburetor project 4 times before I ordered the Edelbrock 1406. Got through most issues, although there are too many, this is a 20-step project, not a 1-step. I have rebuilt engines myself, including my 1963 split window couple Corvette, with no issues, but I'm not a carb expert and the talk of channels and ports and tubes that all need attention and treatment for this to work make it much more complicated than other simple carb swaps I've done. And, after 5 installations with new gaskets and removing the metal shim, etc., it leaks rather copiously from the choke side, no matter what. 

I'm giving up and returning this bothersome carb. Edelbrock had one suggestion for me, order a Transdapt 2406 adapter. But, nobody else has needed this, and it's not clear to me what difference it would make since I appear to have a good seal between the manifold and the carb, except, OH, it leaks a lot of gas!

Makes me sad because, with this carb on, the car starts instantly and idles high. But you can't run it long with a leak. 

I still do not see what holes I'm supposed to plug and I've been through the area inch by inch. I think I'm better off with a rebuilt Carter and have all of these issues. I would have been happy to hire this job out, but I don't think most mechanics these days would do better than I did with this.

Final question, does anything think the 2406 adapter would stop this leak? Photo of my manifold base attached. 

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Pictures of exhaust heat holes to plug are right there on my carb write- up. I never had a gas leak, and if you go thru the write you should come to the conclusion you only have to remove heat riser butterfly, block head to intake center port and install a spacer insulator. That’s just 3 steps to address heat issues. Any gas leaks however would be of grave concern and would assume defect in the carb. I’ve plunked no less than 4 Edelbrock 1406/1411 ‘s down on 429’s, albeit 10 + year’s ago, and used all sorts of gaskets and spacers without any gas leaks.

The issue with the write-up... or learning experience if you will .... was the fact I first attempted to address the extra heat under the carb by simple blocking the 4 exit points: each end of the choke tube, and the top off intake front runner channels (seen blocked in this picture form my write-up). After blocking all 4 points and removing the heat riser butter fly I found the center channel (runs thru center of the of intake from side to side) was still heating up the intake in the center to about 305 degrees from bypass gas. Putting the block plates at the large cylinder head to intake center exhaust port as seen in 2nd picture below eliminated that problem and basically eliminated the need to block the 2 top of intake ports and the 2 internal choke ends, but it would be perfectly find to block these if never considering restoring the intake to stock operation with the need for the stock internal choke tube.
Bottom line is I need to rewrite that article to make much more clear!  ... it's on my to do list!

Greatly appreciate that. I do not have enough experience to do all that you noted. I have read your excellent article and seen all the photos, and that encouraged me to buy the Edelbrock. But I am not familiar with heat riser butterfly, block head to intake center port or all the variables involved in getting this to run right and eliminate exhaust escape channels, or if I got 2 of them it might be useless if I didn't get them all. I don't see 4 exhaust heat holes in any of the photos, so I will just get a rebuilt Carter and put everything as it was. I don't think a mechanic would get this Edelbrock exactly right in the way that you have done by trial and error, rejetting, temperature measurement and such. Just not equipped for this but I gave it a good shot with 5 attempts. Oh, that is also excluding the PCV tube I do not have anywhere under my hood, or the kickdown that can't be attached to the Edelbrock, so one function that you lose, or the fact that the air cleaner no longer fits and neither Autozone or NAPA had an adapter that would seem to work in my visits to 4 stores. I would caution anyone about trying this swap unless they can really hit every single note, and of course the big leak alone is enough to nix the deal. Thanks for your help and attention, the car is awesome and locally famous. 




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