I just purchased a 69 cowl induction set up for my 68 Camaro. Has anyone noticed any real power gains by converting to cowl induction over a standard air cleaner under the hood?

If you seal the carb to the hood, you will notice a small power gain. Chevy had various studies that showed between 10-15 HP with such a cold air setup. You may need to re-jet to optimize for the added airflow.

It's about a 1% gain in horse power for every 11 degrees colder the intake air is compared to under hood air. That's why you use an intercooler for supercharged and turbocharged applications. The boost in pressure heats the air temp, which yields increased horse power if returned to ambient (or you loose 1% for each 11 degrees above ambient, and 1% of a lot in the case of boosted applications hurts more than 1% of a little in normally aspirated applications). See this article about the ZL-2 hood:

http://www.camaro-untoldsecrets.com/articles/rpo_zl2.htm


Larger Dave