Do a couple dyno runs with hood closed, one air filter lid like it's supposed to be and one upside down. I'm not a gambler but will bet on this one because it's already proven a myth. It was a myth before the Internet. Sounds like at least 30 HP though.
It may make a differnce to the good side if your motor is built to put out HP around 5000-6000 RPM.
I still like the stock filter, get another one from JY with tube and take the cold air tube off, flip it over, braze up the hot air tube now on top and add it to stock filter for dual cold air intake, add a Big Block lid which is twice as deep with BB deep filter. Still have the origanal hot air tube for cold weather, it's shuts real fast in summer. This would be a true Hot Rod technique!
Also K&N filters will increase HP, so little you will never notice, this is by letting more air in, less filtered air. Look around for the term Dusted Motor.
The Cold Air Intakes that are not completely sealed do let some hot air in, but it can only be measured with a IAT sensor at stand still. As soon as you are moving the airflow underhood is quickly vented.
It may make a differnce to the good side if your motor is built to put out HP around 5000-6000 RPM.
I still like the stock filter, get another one from JY with tube and take the cold air tube off, flip it over, braze up the hot air tube now on top and add it to stock filter for dual cold air intake, add a Big Block lid which is twice as deep with BB deep filter. Still have the origanal hot air tube for cold weather, it's shuts real fast in summer. This would be a true Hot Rod technique!

Also K&N filters will increase HP, so little you will never notice, this is by letting more air in, less filtered air. Look around for the term Dusted Motor.
The Cold Air Intakes that are not completely sealed do let some hot air in, but it can only be measured with a IAT sensor at stand still. As soon as you are moving the airflow underhood is quickly vented.
