Which carburetor should I rebuild?mild 318

Have to rebuild the carb that was on my mildly built 318, it ran great with the Holley list# 6619-1 which is an emissions carb 600cfm 4160. I also have a Holley 80457-3 which is a 4160 non emissions carb 600cfm.Both carbs are vacuum secondaries. Trying to decide which carb to rebuild, would I gain any performance from running the 80457-3?
The 318 is stock bottom end, pocket ported 302 heads, lunati voodoo cam 60403, Edelbrock performer intake, headers.

The emissions carb will most likely have a little leaner idle. I don't think you would see much difference in HP if either carb is correctly jetted. Not sure on your cam specs, but the non emission carb might be easier to get to idle if your cam is big enough to drop the idle vacuum below 16 inches. The other issue is the power valve restrictions, I would think the non emissions carb would have larger restrictions making it run better at WOT. Of course if you know how to work on carbs, you have numbered drill bits to change things like that.

Aren’t the kits for those less than $30?

Just do both so you can try them both on the motor and see which one to like better.

I had a 6619 back in the day (1976) and I liked it. IMHO it's better than an 1850. For those of you who weren't paying attention back then, the 6619 used higher precision main jets and used a different idle system. You turned the adjusting screws out to lean the idle, and in to richen the idle. I regularly got 19mpg in my 350 '68 chevelle running the 350hp 327 cam (222@50, 114LSA)and dual exhaust.

I have run an 80457 on my 400 Ford. I think that Holley has been tweaking the metering over the last several years and would suspect that it's better than the 6619. But it's probably close.

Engines need different things and maybe one of these carbs will run better than the other on your engine. My 318 in the '64Dog really ran best with a 80570 Street Avenger.

R.
https://documents.holley.com/techlibrary_carb_numerical_listing.pdf

hi

my son runs a 750 vs on his 66 valiant with a 3i8 with 302 heads and runs 13.5 1/4 mile et at the local track. sooooo?