Holley 4 corner adjusting

[rod7515]

Are there any good defining articles to tuning a holley 4 corner carb? I need to work with mine once I get my cooling issue cured. I've never had a 4 corner carb before. I am working with a 750 dp on a 408.
Thanks Rod

 

[brian6pac]

If it's to lean it will run hot

 

[qkcuda]

I assume you are talking idle adjustment. I try to get the primary and secondary throttle blades set to the same opening. You may have to take the carb on and off a few times as the adjustment for the secondaries is a set screw under the base plate. After that it is just adjusting the mixture screws for best idle speed.

 

[mopardude318]

I thought I read on here that having a 4 corner idle adjustability was a moot point on a vacuum secondary carb?

 

[12many]

I'd recommend buying this book by David Vizard, great reference that explains everything (I refer to it often as I'm learning and tuning mine) or you might be able to preview the idle section via google preview:

 

[MOPAROFFICIAL]

Set them all evenly.

 

[Mattax]

Are there any good defining articles to tuning a holley 4 corner carb? I need to work with mine once I get my cooling issue cured. I've never had a 4 corner carb before. I am working with a 750 dp on a 408.
Thanks Rod

It's pretty much the same as any carb. Once the engine is warmed up, adjust them 'til it runs the best, then set them a wee bit richer if you were only checking in neutral. With an automagic you can put it gear and check the vac and rpm abd tweak it a little closer.

Here's the deal. A four corner idle that is calibrated the same as a 2 corner doubles the circuits that see manifold vacuum. This means fuel flow at idle can be doubled.
Four corner can be helpful if the idle vacuum is poor, and a PIA if the idle vacuum is strong (over 14"Hg).
In between, it should be OK, you'll just have to play with it. Having control over the different corners may help because they can be tweaked for more even distribution to the cylinders.