There are stock provisions for this. On 1981-91 I know there is tube off the aircleaner running to the front clip that sucks in cold air when you're going down the road. There just happens to be the exact same opening on the driver's side but has a plate tacked in place. A hammer and a punch and the plate will come right out and you can rig up dual ram air. On a pre '81 I believe there is a provision for ram air on the passenger's side of the clip. I think the tube for the pre 81's is more round and the post '81s are oval. Any who, your clip should have a provision for cold ram air. Somebody who has this setup on a pre '81 should come along here and fill in my vague details.
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