JBM1960

Does anyone know the base drop distance for 63 340 HP air cleaner? Changing from AFB to AVS2. Need to change base because of 41/4"-51/4" difference. Concerned about hood clearance.
Any recommendations on drop base suggestions would be appreciated.
Thank You

kingwoodvette

PM Vet65te. He recent dealt with a similar problem.

Vet65te

Hey Jeff and Randy - for the longest time, I was using a 66-67 style open 14" Corvette air cleaner on my 65 300 horse Coupe. I bought it back in '85 and it had been through the ringer by then and the
original twin snorkel air cleaner was MIA. I do have the original cast iron intake but am running an Edelbrock #1406 carb. Just recently, a friend from the Phoenix/Scottsdale Valley happened to put one up for sale so I bought it
and once I had it in my possession, realized those early carbs were quite small when compared to the later model Edelbrock. Got out my stash of air cleaner adapters but nothing seemed to neck down far enough and didn't find anything at Summit or any of the other vendors.
Looking at the underside of the twin snorkel cleaner base, it seemed I could use the straight adapter...one that would typically just raise the base up about a half inch, mabye 5/8 inch, and let that come up around the small/narrow neck
of the twin snorkel base. To make it actually seal well enough, I will have to line that upper edge/surround with some sort of gasket material but it seems like it should work okay.
Mike T - Prescott AZ

JBM1960

Thanks Mike T for the information. I can not use my existing AC AFB base since the base opening is ~41/4" and the AVS2 is ~5/1/4". I was hoping to purchase a 51/4" drop base but I am not sure what the drop distance is. I can not measure the 63 drop base since the car is not with me now. I think I will have to modify what ever base I purchase to clear the electric choke. I want to keep my 63 base and AFB so I do not want to hack the base up. Edelbrock 1211 is recommended to fit the but I think the 3.75" net height will hit the hood. If someone could measure their drop I could purchase one with the same drop and deal with the choke modification.
I put an AVS2 with manifold plate adapter on my 1960 and used a K&N flat base PN-154, Edelbrock banjo fuel line and filter with no clearance problems it was close but no hood issues.
Thank You

kingwoodvette

Try purchasing a 1/2” carb extension in the 5 1/4” size. It’s less than $10. Place it on the carb and then place your air cleaner on top. Most of these bases have a bit of a snout that will fit down into the spacer. If this combo will still allow your hood to clear, make a gasket out of rubberized cork and slide onto the “snout”. You can see this snout in the pictures that Vette65te provide.

I was able to use this technique on a 64 Pontiac going from an AFB to an Edelbrock and retain the original air cleaner. Good luck.

JBM1960

Thanks for getting back. My 63 air cleaner opening is 41/4" so I can not use a 5/14" adapter. I think I will have to purchase a new drop base but not sure what what drop base dimension I need to to clear the hood. I called Edelbrock and they said Corvette users are using Mr. Gasket 1480 air cleaner and base. https://www.summitracing.com/parts/mrg-1480
Thanks again.

toddalin

I would (and do) use use the regular Corvette drop base to put a Holley on on '64 (Edelbrock Performer RPM intake). This is made to the wider carb opening. If you find that it drops the base too much, you can always as a carb spacer, but probably won't need it,

https://www.ecklers.com/corvette-ope...oogle&utm_term

JBM1960

Thank You that's good to know.