Hi, has anybody changed original intake manifold w/carburator to aftermarket one? Which one will fit under original hood w/o scoop? Which manifold and carburatos you have? I want to change original quadrajet to Holley (streetavenger 670cfm).

Ismo

1969 topless 350cc

Hey,
I put an Edelbrock Performer intake and 600cfm carb on my '77. Just clears with a 3" K&N air filter on top. It was a great mod and I'd definitely recommend it.

There is a method using little pieces of clay on top of your air cleaner to determine how much clearance you have between the stock configuration and the hood. Just place some modeling clay at three places ( like a triangle ) on your air cleaner and gently close the hood. Then measure how thick the clay is and you can see how much clearance you have. With that information in hand, call Edelbrock or Holley or who ever you are going to buy parts from and tell them the car ( Vette ) year, and engine size and they will tell you what manifolds and carb setups will fit. I know for sure Edelbrock will go right into their CAD program and tell you down to 100 of an inch what fits and what won't. I spent some time on the phone with them when I was deciding to change over to fuel injection. They determined that their unit would not clear the stock hood by some riduculas small number but when I said I had access to an L88 hood, they told me exactly how much clearance I would have.
Only takes a few minutes to do all this and believe me, it is cheaper and easier than replacing a cracked hood.

I just put a Weiand ActionPlus intake and a Road Demon carb on my stock 76 L48. A Summit drop base aircleaner sits on top.
Between the intake and carb is a 1/2 inch spacer. There is more clearance between the hood and aircleaner now than with the original parts! Even without any other mods, there is a noticable difference in power.

I've got an edelbrock performer intake with a holley 600 carb on there, which is sitting on top of a 1-inch carb spacer. Then on top of that, I had to put another 3/4ths inch space to get the silly dropped-base chrome air cleaner from Summit with a 2 inch element inside. I can't put a wing-nut on there, it's kills the clearance (thank you Play-Doh)

Imran -

I have the Performer #2101 and a Holley 650 vacuum sec. #4175 spreadbore. I had to raise my stock aircleaner 1/2" to clear the vacuum module but still have plenty of room.

I put an edelbrock torker II with a holley 750 carb. It just clears, all other manifolds require hood modification. I have a 70' LS-5 454.

in my '75 i changed to an edelbrock performer intake and carb. The small block cowl hood of course gave me some space but i also used the edelbrock pro flo air cleaner which gave me exrta space as well. you shouldn't run into problems until you get to perormer air gap intakes of victor intakes. then again there's always a big block hood

I put an Edelbrock performer EPS intake and an Edelbrock 750 carb on my '79 with a 14" cleaner. Had plenty of room.
Glen has a great idea with the clay.