Cowl Induction....
Thread Starter
Le Mans Master
Joined: Jan 2001
Posts: 6,742
Likes: 1,384
Cowl Induction....
I did a little experiment this morning. I taped some fiberglass strands from some fiberglass cloth onto the top of my L88 hood scoop. Amazingly it flipped over was getting sucked into the cowl by the time I hit 15 mph. I'd see pictures on this forum before, but it was quite dramatic to see it with my own eyes.
Tech Contributor
Joined: Jun 2004
Posts: 20,905
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
I've got the L-88 scoop on my '69. I had to do the same experiment to see for myself. It's pretty neat watching the action of the airflow. 
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
and...... ???
I haven't seen any previous posts of the air flow....
What are you intimating. that the air flow is erratic? or laminar? or does it indicate a low pressure area at the opening at the rear of the bonnet... what?
I have just orderred an L88 scoop to fit to my bonnet for air cleaner clearance....
Are the bonnets you guys have true L88 style with the airbox? or simply open hi rise interior surface?
Some pics of the underside would be good.
cheers
I haven't seen any previous posts of the air flow....
What are you intimating. that the air flow is erratic? or laminar? or does it indicate a low pressure area at the opening at the rear of the bonnet... what?
I have just orderred an L88 scoop to fit to my bonnet for air cleaner clearance....
Are the bonnets you guys have true L88 style with the airbox? or simply open hi rise interior surface?
Some pics of the underside would be good.
cheers
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
It should be rather obvious that you won't get the benefit of cold air cowl induction w/o a box isolating the carb from hot underhood air, but I've read of tests showing that there's enough pressure developed at the base of the hood to direct airflow into the back side of the L88 cowl w/o a box at speeds as low as 30mph. IMHO, this puts a fly in the soup for guys who believe running with the hood cracked helps get more air thru the rad on a hot shark, and I wouldn't suggest opening up the cowl w/o a box. With my upcoming 4500, I'm probably going to be forced into a NastyCar type box like the ones AllStar has.
Last edited by TheSkunkWorks; Nov 15, 2007 at 01:35 AM.
Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
I do agree with you though. Without some type of seal around the air intake you won't get the same benefit.
Pro
Joined: Jan 2006
Posts: 599
Likes: 0
From: New York
Cowl induction is the better route to take because your taking cold dense air at the high pressure area which is at the base of the windshield n ducting it into the carb creating a more dense fuel charge resulting in more HP..I think it is about a 1% gain in horse for every 11 deg. decrease in temp.....
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
http://www.allstarperformance.com/catagories.htm Download the catalog and look in Fuel Systems for Air Pans (pg 66)
Last edited by TheSkunkWorks; Nov 16, 2007 at 02:24 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
