Dump that stock airbox for cone filters!

[Serious Eric]

... And LOSE 20 hp!

Went to a dyno day at Auto-Tek with Dave Weaver (Viper tech/guru) and the central Tx club. Made two pulls on their Dyno-Jet; First with stock airbox (front baffle removed), smoothies and dirty K&Ns -> 426 peak SAE Hp, 463 ft.lb torque. Second pull we yanked the airbox and let it breathe through the open smoothies -> 406 peak SAE Hp. The losses were same THROUGHOUT the rpm range!

Only thing I can attribute this to would be intake air temp. With the airbox removed, the smoothies (and cones if you had 'em) were drawing air from right behind the radiator.

I think that in a real-world situation the difference would be even greater. On the dyno, the hood was up 8" at the front (both pulls) which should tend to reduce the difference between ambient intake temp and underhood air temp.

BTW - ambient conditions were 89 deg F, 58% humidity, don't remember barometric pressure. Fan blowing air onto front of car. Thanks to all concerned for a great Dyno-day. Can't put my finger on it, but I think the numbers from that machine were a bit low. I know my car has pulled 449 Hp in the same trim and almost everybody else who had dynoed before saw similarly reduced numbers ... well that's chassis dynos for ya.

 

[Chuck 97 GTS]

Eric, where was your intake air temperature sensor when you made the second dyno run?

 

[Serious Eric]

Intake air temp sensor was measuring room ambient (not under hood) for both runs. Sensor was on the dyno room wall 6 ft from the front of the car.

 

[Vip-RT10]

Cones look good, but they need fresh cool air to have them work the best, if not, only loose HP....

 

[Bill Pemberton Woodhouse]

Absolutely no doubt that the cones look phenomenal. The idea won't go away about horsepower because many feel a Dyno is gospel.The one item that can not be adjusted on a Dyno is true airflow, and with the hood up the cones will pull more air to the motor. Rockin and rollin down the highway or track the stock box force feeds air down the throttle bodies, and the air swirls around the cones. Surprizingly , a good friend of mine sells a ton of Vettes, and they say the same thing ----- cones look cool, but don't draw air properly at speed. Nuff, said, but like Jon I agree that the cones look COOL !