I remember seeing something awhile back from a guy who said he was looking for a carb adapter to go from 1 barrell to a 2 barrel.Then I saw a picture of the setup.Wondering if that will really increase performace.how could it?? I had a friend in highschool that adapted a holley 4 bbl. on a 318 2 bbl intake and it ran like crap !!!!

It would allow more air to flow into the engine, but you have to remember the air must also exit the engine as well. Unless the exhaust is up to the task, adding a bigger carb will not gain you anything.

i put a holley 5200 on a 1bbl intake with an adapter from proline. performance increased about 30%. mpg went from 13 to 19. also went with 2 1/4 single exhaust noticeable improvement. if you want an easy quick upgrade the adapter is fine or you can go intake and carb .my way took about 45 minutes and i love it

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73 swinger holley 5200, 2 1/4" exhaust .030 over new pistons , cam, .010 under crank. stock everything else. 1/4 mile about a week. 0-60 around 15 sec.

If you were only getting 13mpg with your 1 barrel, your carb was likely out of tune or there were other issues.