Just about on cloud 9!

[Mike_The_Grad]

Hooray!!! I figured something out all on my own! Really, because I couldn't even find it searching these forums.

Back story (not to long): I recently found an Edelbrock Performer series 2101 intake manifold for my fresh rebuilt 350 in my '72 LWB for a steal on craigslist. $60 and I had the last piece to my build (in my eyes).

I know what your thinkin Big Whoop! And that's OK. But here's the issue I been having: I have the factory 1972 4mv Qjet still,(no that's not the issue...☺) casting number#7042910. Listed as 1972 chevy pickup automatic transmission, CA emissions. It came from the factory on one of those "Hot Slot" manifolds.(exhaust crossover under the carb base.) Well it also has an irregular spread bore mounting flange.
I researched hi and low trying to figure if this was something that could potentially cause a fitment issue. Every forum,every post, vendor website, you name it, said that the 2101 is a spread bore manifold for spread bore carbs. Period.
So I went with it. I used a standard base gasket and mounted the carb. From that exact moment up until now as we speak, I have had nothing but issues with this "upgrade". First, couldn't even get the thing started, then couldn't get it to idle,then this, and that.....you know the scenario. (Actually it was a blessing in disguise because it finally made me set my float level correctly, and really figure out my timing to the point that I got it nailed down, and perfect for my setup.)
My gut was telling me this carb and manifold wasn't mean to be.
I was half right.
I found out that edelbrock makes an adapter plate for irregular flanged spread bore carburetors! Big whoop right? Lol. Well this adapter is not mentioned in any forum of any poster going through the same exact issues. They are simply met with replys like, "it's a spread bore, it's a spread bore manifold, they work together." Or the typical opinion of the "quadrabog" or "quadrajunk" or "just put a holley on it"
I knew my persistence would pay off. I found this adapter plate existed while on a subsection page of edelbrocks main site. No footnotes mentioned in the instructions, no cross references, shoot I couldn't even find a post on here with the part number even stated. (Which is edelbrock part #2731 BTW)
I'm sure if I sat here for hours on end like I have in the past I may find one or two posts, but nowhere near the number of posts sharing the same scenario I have been facing.
All in all, I'm relieved to have finally resolved my issue,taking for granted that that is the only source of my vacuum troubles.😆
I hope this information proves useful to someone not unlike myself, who is about ready to throw in the towel and accept defeat.

And if you do not have this problem personally, consider yourself informed, and please share the info with those "priveldged" Quadrajet owners you are all too familiar with 😊

[demian5]

I just rebuilt an edelbrock q jet for my friends 68 corvette without seeing the manifold. When the carb showed up it had a metal base gasket with silicone all over it. I gave the carb back to my friend with the new base gasket and the metal gasket, telling him not to use the metal one. Turns out it had this manifold on it and had an exhaust leak under the carb (had never experienced that). He put the metal gasket under the new base gasket (with eome silicone) and voila! It was fixed.

That was a first for me.

[70cst]

Its always good to have those truck victories in life - Congrats

[hugger6933]

I thought it was common knowledge that the performer intake while a good piece, it is known for vacuum leaks.