Belly pan for top speed
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,638
Likes: 3
Belly pan for top speed
well it's that time of year again - we are trying to wring top speed out of an 82 C-4. The rules for the class we are in allow for a belly pan - but it can only cover 50 % of the bottom of the car. The rules also disallow any modification of body panels (no higher spoiler - no lowering the airdam etc)
It looks like we will be running about 185 - 190 - and we are hoping for anything that can bump us a little toward the goal of 200mph.
anyone with real world experience here?
We are thinking about several approaches
cover the engine compartment and the rear?
or what about covering the drive shaft - the middle 1/3 of the underside?
Turn the rear unit into a difuser like Burners has?
And is it even worth it - any idea what kind of speed we will be adding?
See ya at World of Speed sept 14 - 17
Carl Johansson
It looks like we will be running about 185 - 190 - and we are hoping for anything that can bump us a little toward the goal of 200mph.
anyone with real world experience here?
We are thinking about several approaches
cover the engine compartment and the rear?
or what about covering the drive shaft - the middle 1/3 of the underside?
Turn the rear unit into a difuser like Burners has?
And is it even worth it - any idea what kind of speed we will be adding?
See ya at World of Speed sept 14 - 17
Carl Johansson
Racer
Joined: Mar 2004
Posts: 292
Likes: 2
From: Plumas Lake CA
I wonder if you can run a wider (lower) rubber airdam strip? It is not really a body panel 
. Anyone try to get that past inspection yet? I would guess your biggest improvement would come at the rear of the car. I'd work on the backend first - a diffuser would be a cool setup to reduce your drag out back. Maybe a little work on the actual floor of the car would not count against the 50% rule, leaving more of the underside to focus on.
. Anyone try to get that past inspection yet? I would guess your biggest improvement would come at the rear of the car. I'd work on the backend first - a diffuser would be a cool setup to reduce your drag out back. Maybe a little work on the actual floor of the car would not count against the 50% rule, leaving more of the underside to focus on.
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Without being able to lower the front air dam you will need to get the car as low as possible. Would they allow side skirts if they were bolted to the frame?
I wonder it air deflectors just behind the front suspension to direct air out behind the front wheels would be allowed.
BigBlockk
Later.....
I wonder it air deflectors just behind the front suspension to direct air out behind the front wheels would be allowed.
BigBlockk
Later.....
Melting Slicks
Joined: Jul 2002
Posts: 3,000
Likes: 22
From: Boulder Creek California
From reading Racecar Engineering, improved airflow under the car by way of a diffuser behind the airdam in front or a diffuser in the rear can actually lead to more drag. Sounds crazy at first but more airflow instead of slow, confused air means more air hitting obstructions. My first priority would be to smooth obstructions rather than produce downforce if you're not having instability problems. Keeping air from getting stuck in the rear and the plethora of other crevices would be very good.
