Holley 4150 baseplate gasket incorrect?

Metalmarty

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Hi all,

I've bought a secondhand Holley 4150 Double pumper with manual choke. Model number 4779-9.

I'm in the process of cleaning it and installing new gasket, which was much needed. To do this I've bought holley kit 37-485.

But it looks like they've supplied the wrong throttle body gasket. This is the only one of the four included gaskets that remotely fit. But the right top hole as seen in attached pictures is incorrect.

When I look at pictures of the 37-485 kit it should have a gaskets where the holes are correct.

Is this the wrong gasket?
And am I correct that the holes that are covered by the new gasket are the idle corner holes?



Edit: I took another look. My gasket has 1-11/16 holes.

They have included 2 exactly the same gaskets with 1-9/16 holes, one 1-7/16 holes and one with 1-3/4 holes. Seems that the one I need is not in the kit...

Seems like a packing error. Which I also had woth the holley throttle adapter. That was missing one of the screws. Both adapter and carb renew kit in sealed packaging :(

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I discovered recently that the holes in the factory intake manifold for the 1.69" throttle bores are really 1.75". I suspect that as long as the other holes match, the larger gasket might be the one you need. Of course, you can always call the Holley Tech Line or send them an email.

The other thing is that possibly, over the years, they have "universalized" the kit to fit many Holley 4150s. Which might explain the other smaller throttle bore gaskets.

I suspect there might be some info on the Holley website as to which holes do what in the throttle body and main body?

Hope this might help.
CBODY67
 
I wouldn't be concerned with the slight oversize of the gasket versus the throttle bores.
Where it does not match the small vent ports bothers me. Unless, it can accomodate the holes resized.
 
Did the old gasket leave those holes uncovered? Sometimes this stuff is goofy, like head gaskets that cover some of the water jackets
 
That gasket is for an 850. Will not work for a 750.
 
My trick kit came with 4 base to body gaskets, there are 2 like the one you have and 2 that have the angled holes, the one that fit my 4779 was the larger bore with the angled holes, that gasket is wrong.
My $.02
 
That gasket is for an 850. Will not work for a 750.

My trick kit came with 4 base to body gaskets, there are 2 like the one you have and 2 that have the angled holes, the one that fit my 4779 was the larger bore with the angled holes, that gasket is wrong.
My $.02

Thanks for the tips.
I found out that Holley packed my renew kit incorrect.
The website advertises a 37-485 renew kit for a 4779-9 carb, which I ordered.
I got two of the same body gaskets, but the 4779 gasket is not here (and 2 of the base to body gaskets are identical).

I found someone in the Netherlands that had a spare base to body gasket which he will ship to me
 
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