c4 aerodynamics for less drag
Thread Starter
Advanced
Joined: Jul 2013
Posts: 92
Likes: 2
c4 aerodynamics for less drag
So I'm tweaking my street driven -96 for standing mile events and I would like to know what there is to do for less drag.
I already have rear diffuser that smooths out the area after rear diff, but can anyone come up with something else?
Thanks guys!
I already have rear diffuser that smooths out the area after rear diff, but can anyone come up with something else?
Thanks guys!
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
And make an air dam that does to the ground across the front, and down both the rockers.
Take off the side view mirrors.
Block airflow through the radiator (to the extent that it can maintain temps through the run)
Disk wheel covers.
Drifting
Joined: May 2007
Posts: 1,552
Likes: 324
From: Mid Ohio
#1 drag is frontal area. The more perpendicular to direction of air the worse the drag. (not much you can do about this w/o body work).
#2 is air flowing through engine room, under car, tire wells, and behind rear. This is dirty (turbulent) air flow that adds drag / consumes power. Small things that help are taping off frontal openings and removing the seal between hood and firewall. (lets the high pressure in the cowl area bleed down the firewall and helps sweep away heat off the exhaust)
Best way to help both of those is to lower the car as much as is possible.
Next best thing is to get the engine into the TQ peak as quickly as possible in top gear.
Everything else is just a matter of increasing efficiency of something that is already helping or hurting you.
- Brakes dragging? (do a quick left / right bobble of the steering wheel after you launch to help the front pads move away from the disk)
- Remove mirrors
- Make a true ram air system to help pack the intake w/cool air. In place of the front license plate is a great way to kill two birds with one stone
- Take about 3/4 of a quart of oil out of the engine (from the full mark)
- Install a alternator cut out switch
- Make sure the cabin body vent is operating
#2 is air flowing through engine room, under car, tire wells, and behind rear. This is dirty (turbulent) air flow that adds drag / consumes power. Small things that help are taping off frontal openings and removing the seal between hood and firewall. (lets the high pressure in the cowl area bleed down the firewall and helps sweep away heat off the exhaust)
Best way to help both of those is to lower the car as much as is possible.
Next best thing is to get the engine into the TQ peak as quickly as possible in top gear.
Everything else is just a matter of increasing efficiency of something that is already helping or hurting you.
- Brakes dragging? (do a quick left / right bobble of the steering wheel after you launch to help the front pads move away from the disk)
- Remove mirrors
- Make a true ram air system to help pack the intake w/cool air. In place of the front license plate is a great way to kill two birds with one stone
- Take about 3/4 of a quart of oil out of the engine (from the full mark)
- Install a alternator cut out switch
- Make sure the cabin body vent is operating
Last edited by wydopnthrtl; Aug 22, 2014 at 07:46 PM.
Racer
Joined: Jun 2014
Posts: 328
Likes: 2
From: Mesa AZ
#1 drag is frontal area. The more perpendicular to direction of air the worse the drag. (not much you can do about this w/o body work).
#2 is air flowing through engine room, under car, tire wells, and behind rear. This is dirty (turbulent) air flow that adds drag / consumes power. Small things that help are taping off frontal openings and removing the seal between hood and firewall. (lets the high pressure in the cowl area bleed down the firewall and helps sweep away heat off the exhaust)
Best way to help both of those is to lower the car as much as is possible.
Next best thing is to get the engine into the TQ peak as quickly as possible in top gear.
Everything else is just a matter of increasing efficiency of something that is already helping or hurting you.
- Brakes dragging? (do a quick left / right bobble of the steering wheel after you launch to help the front pads move away from the disk)
- Remove mirrors
- Make a true ram air system to help pack the intake w/cool air. In place of the front license plate is a great way to kill two birds with one stone
- Take about 3/4 of a quart of oil out of the engine (from the full mark)
- Install a alternator cut out switch
- Make sure the cabin body vent is operating
#2 is air flowing through engine room, under car, tire wells, and behind rear. This is dirty (turbulent) air flow that adds drag / consumes power. Small things that help are taping off frontal openings and removing the seal between hood and firewall. (lets the high pressure in the cowl area bleed down the firewall and helps sweep away heat off the exhaust)
Best way to help both of those is to lower the car as much as is possible.
Next best thing is to get the engine into the TQ peak as quickly as possible in top gear.
Everything else is just a matter of increasing efficiency of something that is already helping or hurting you.
- Brakes dragging? (do a quick left / right bobble of the steering wheel after you launch to help the front pads move away from the disk)
- Remove mirrors
- Make a true ram air system to help pack the intake w/cool air. In place of the front license plate is a great way to kill two birds with one stone
- Take about 3/4 of a quart of oil out of the engine (from the full mark)
- Install a alternator cut out switch
- Make sure the cabin body vent is operating
Tommy
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
I agree with lowering the car to get the tires out of the air stream and inflating the tires to reduce rolling resistance.
Lose the spare & jack and arrive with 1/4 tank of fuel to reduce weight and aid acceleration.
Lose the spare & jack and arrive with 1/4 tank of fuel to reduce weight and aid acceleration.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 413
From: WV
Just know that the C4 Corvette was one of the most aerodynamic cars built in it's day in it's stock form so your way ahead of the game to start with. Below are the numbers for Coefficient of drag..
....WW
Coefficient of drag by years:
'73 .325 (X-882 Mid-Engine 4-Rotor Wankle Corvette)
'80 .443
'84 .34
'86-'90 .33
'91 .29
'96 .31
'97 .29
'98 .29/.32 (Conv't)
'99-'03 .29/.32/.31 (Fixed Roof Coupe)
....WWCoefficient of drag by years:
'73 .325 (X-882 Mid-Engine 4-Rotor Wankle Corvette)
'80 .443
'84 .34
'86-'90 .33
'91 .29
'96 .31
'97 .29
'98 .29/.32 (Conv't)
'99-'03 .29/.32/.31 (Fixed Roof Coupe)
Last edited by WW7; Aug 24, 2014 at 08:05 AM.
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Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
great to see a member doing the standing mile events. I'd like to get involved but first I have to get my car running good. How much power do you make and how fast do you want to go?
Thread Starter
Advanced
Joined: Jul 2013
Posts: 92
Likes: 2
Last year I did 163mph. My current goal is to make 168mph without touching the engine.
Last edited by Tapio@FTTRacing; Aug 23, 2014 at 11:48 AM.