Milled choke horn

Does anybody have any track proven numbers comparing running a carb with the choke horn milled off versus not milled off?

650 DP w/ milled and no other changes picked up .03-.04 consistently. W/ jet changes to match, picked up a total of .05-.06. That was in 1984 on my first car. Since then, I pretty much delete it right from the start. Anymore, I just buy a main body w/o it and go from there. Given that I "proved " the mod a long time ago, others may be getting different results today. I'm interested in seeing if others are going to back me up or tell me I'm full of it. Could be an interesting test on a modern engine. If an argument breaks out, I have the parts to swap around and test it. My car runs 12.30's at 110 at 5800' in elevation. The elevation itself is a factor that could change my results in comparison to a sea level motor, so maybe someone down low can also validate the results.

I like this question, the 4500's have them cut off. I read something in my holley book about it

gains in air-flow but you should radius the edges around the the sides

Milling the choke horn off a Holley without doing any other mods probably will not gain anything. The old Carb Shop modified the 3310 on my Falcon by removing the choke horn and adding 4 corner idle and other mods which was good for a .50 reduction in the 1/4.

I have tested this many times, and unless lots of work is done to the entry of the carb, BESIDES the choke milled off, NOTHING will happen, It does NOT pickup anything on the flow bench or on the dyno. Now let me say this, IF the carb has been rerworked by someone who knows what they are doing, it CAN gain up to 30 0r 40 CFM, BUT not by just cutting off the choke.The smaller the carb) (650-750 ) the LESS you might gain. I have reworked carbs and used the flow bench to verify the results. The biggest gains come from making all four barrels flow the same. From Holley, they very quite a bit( 5 to 10 ) CFM.

JOE SHERMAN RACING ENGINES

I think it is important, which airfilter is above the carb.
On a sunbeam tiger there is only little space above the carb and therefore the airfilter is very low.
In this case, there are some gains from the milling as the air can flow much easier into the carb. In other cases, with a tall airfilter, there will be no or not much benefit from the work.

regards
Hans

My engine builder has done this on some of his motors and has patented an airflow device that has actually picked up around 10hp more on the dyno. The device actually directs the air from all 4 sides straight into the carb. I'll be getting it done to mine this summer. It may push my power over the estimated 475hp mark.

I was considering up dating my old 4781 850 holley with one of the Proform carb bodys . How do they work would I see any gain in flow any are they wroth while.

Depends on the car/motor combo. I haven't finished completely with the carb, but initial tests show that the new 750+DP with ProForm and QuickFuel parts runs the same numbers as the old swap meet 650DP with the choke horn on it. And this is with a big converter and big gears.
Similar carb jetted the same picked the Mustang's 2V engine up .02+ in the 60's alone and added about 2 MPH.
So on specific applications I've tested here, a 750 vacuum secondary body did improve power on a 3310 but so far the DP setup has not. Other combinations will vary.

I would guess that if the carb was just a little too small for the app, taking that extra restrition away might free up a little airflow, and gain a little bit of power, but when the carb can flowing plenty of air, it probably wont do anything, just like going from a 650 to a 750 may not help anything on certain engines