ProComp has an Airgap duel plain manifold, i just put one on my 79 Elky, polished version PC- 22025 1500 to 6500 RPM recommended. I don't know how it works yet because i'm still making brackets for the AC, i also put a small .510 hydraulic cam in it, the other one went flat. I have alum heads and 1 5/8 headers, had a 750 vacuum secondary carb (too big) i'm going to a 650 vacuum secondary. Don't know yet what it will run but it went 8.46 in the 1/8 with old setup on street tires. I have a 200R4 Buick grand national trans and 4.56 gears. I took an Edlebrock manifold off of the car. I did the full dress up with hand welded valve covers and crome brake booster and master cylinder. But in the end it's all worth it, i've the car for over 25 yrs. and it look better than the day it rolled off the showroom floor.
Zip.
