Intake Manifold/Weber 32/36 throat mismatch

[Highlander]

OK guys, So I finally pulled out the 32/36DGEV to work out an adapter design, and I'm a bit concerned about the manifold opening vs the carb throats. The original manifold has the primary furthest away from the engine and the Weber, if placed with the choke furthest from the engine, puts the primary in the same place. Here's where I'm concerned, the intake manifold has a larger opening for the primary than for the secondary. The Weber 32/36 (as the name implies) has a larger secondary throat than primary.
SO, did those of you who changed to the Weber notice this?, and did any of you do anything to port match the diameters? I know that someone has said that their 32/36 doesn't need to use full throttle plate opening since it doesn't accelerate after a certain throttle position. This could be caused by the restriction of flow after the secondary throat.
Since I have an extra intake manifold, I'm considering mod'ing the manifold to fit the Weber more easily (plug the stud holes that are outboard and use the inboard ones with a couple of newly placed ones to keep the height down. I might be able to make two adapters, one for the stock manifold, and one for the mod'd manifold and try both to see if there's a difference (a lot more work though).
Does anyone have any thoughts on this?

[splatterdog]

I port matched my intake to the adapter. Just the center of the opening though(as shown in my first weberiffic post photo). I also beveled the underside of the intake opening.

The only thing I noticed is much better driveability. I was/am very pleased with the bolt and go setup.

[ARCHINSTL]

splatterdog -
Did you remove the material colored black on the sides of the hole in your first photo? I forgot to ask when I did my install, as I was in too much of a rush to do the job (and did NOT feel like removing the manifold).
As mentioned, my setup is pretty much identical to yours, save for a different gauge and leaving a gas filter tube hooked up to the upper front port of the dist.
Tom M.

[splatterdog]

Those black marks were removed. Towels stuffed tightly in each primary runner kept shavings under control.

[Snax]

I don't know that you are really looking at much flow restriction with a mismatch. My motor simply can't use the 32/36 at anything over 3/4 throttle. It just makes more noise.

Edit: On the other hand, my issues with a possible clogged cat may be a factor there, so . . .
Edit2: 34/34? What was I smokin'?

[Petros]

Making a better fit intake manifold is always a good idea. The better it breaths the better it will perform. Enlarge it as much as possible and round off all the sharp edges. It should improve both power and economy. A taller manifold might improve performance a bit, but you have the hood clearance issue as well. I would not want to alter the hood, so lowering the carb is your only option.

With a rotary file on a drill you can do a lot. A high speed die grinder driven by compressed air is the fastest way to do it, but a drill works too. Sand the intake smooth if possible using small sanding drums, a sanded mat finish is best. Do not bother with polished surfaces, too much work and no gain.

Good luck

[animeracing]

The bolt-on adapter is a compromise in a lot of ways, mainly just designed to fit the Universal 32/36 carbs onto the stock manifold with the least amount of hassle.

You can definitly improve on the design by either making your own, or even better, modifying the manifold itself to fit the weber.

Modifying the manifold itself would be a lot of work, and require the use of a TIG welder since it's aluminum. The results could be worth it though, with a near stock height carb, and zero bottlenecks.

While it's true to some degree that the 32/36 Weber can deliver more than the stock 3A/3A-C can use, more modifications to take better advantage of the carb are possible, but you hit the point of diminishing returns pretty quick and wind up getting small power gains for increased fuel consumption and less long term reliability.

A replacement cat, along with a better flowing muffler will usually yield some modest gains, especially over stock, and those in poor shape.