C4 rear diffuser
Thread Starter
3rd Gear
Joined: Oct 2012
Posts: 3
Likes: 3
From: tucson arizona
C4 rear diffuser
hi guys,new around here,since nobody makes aftermarket support for us c4 guys i thought i would try helping us out.i have many plans i will make but the first project is a rear diffuser for the c4..i already have one on my car and it looks great..right now i have very limited pictures but im getting more for you guys..how many of us c4 guys would be interested in something like this???? heres just a tease
Racer
Joined: Oct 2007
Posts: 321
Likes: 0
I agree. I really wish we had some more support in the C4 community as far as mods go like a rear diffuser. On the same subject, heres the one I just finished up a couple months back. I love it. Entirely made out of fiberglass with a 3 ply carboard skeleton.
Le Mans Master
Joined: Oct 2007
Posts: 9,685
Likes: 3,437
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
Are you guys doing this for cosmetic purposes or looking for actual downforce? The two pictured are too far off the ground to be effective. A real diffuser will make street driving hard without knocking it off.
In order to make downforce the diffuser has to start around the middle of the car, or at least in front of the differential, and then gradually open up to the back. From a fuctionallity stand point the two pictured here are just THIS with some fins on it for looks. While they will keep air from building up inside the bumper, they are not performing the functions of a diffuser to make downforce.
Race teams spend thousands of dollars, and tremendous amounts of time to get the angle right, fin size and locations, etc. etc. Without that knowledge you may actually hurt the aero balance of the car by guessing.
In order to make downforce the diffuser has to start around the middle of the car, or at least in front of the differential, and then gradually open up to the back. From a fuctionallity stand point the two pictured here are just THIS with some fins on it for looks. While they will keep air from building up inside the bumper, they are not performing the functions of a diffuser to make downforce.
Race teams spend thousands of dollars, and tremendous amounts of time to get the angle right, fin size and locations, etc. etc. Without that knowledge you may actually hurt the aero balance of the car by guessing.
Thread Starter
3rd Gear
Joined: Oct 2012
Posts: 3
Likes: 3
From: tucson arizona
Are you guys doing this for cosmetic purposes or looking for actual downforce? The two pictured are too far off the ground to be effective. A real diffuser will make street driving hard without knocking it off.
In order to make downforce the diffuser has to start around the middle of the car, or at least in front of the differential, and then gradually open up to the back. From a fuctionallity stand point the two pictured here are just THIS with some fins on it for looks. While they will keep air from building up inside the bumper, they are not performing the functions of a diffuser to make downforce.
Race teams spend thousands of dollars, and tremendous amounts of time to get the angle right, fin size and locations, etc. etc. Without that knowledge you may actually hurt the aero balance of the car by guessing.
In order to make downforce the diffuser has to start around the middle of the car, or at least in front of the differential, and then gradually open up to the back. From a fuctionallity stand point the two pictured here are just THIS with some fins on it for looks. While they will keep air from building up inside the bumper, they are not performing the functions of a diffuser to make downforce.
Race teams spend thousands of dollars, and tremendous amounts of time to get the angle right, fin size and locations, etc. etc. Without that knowledge you may actually hurt the aero balance of the car by guessing.
Race Director
Joined: Jun 2004
Posts: 13,957
Likes: 706
From: WI
It looks like that can go on in addition to the spare tire assembly?
Kubs, I was wondering if I would see any difference at the drag track with my plate on there. I trapped almost 117 and I didn't see enough difference from last time to say it helped. NASA Road America is this weekend, I'll be sure to inspect any data to see if there is a benefit.
Kubs, I was wondering if I would see any difference at the drag track with my plate on there. I trapped almost 117 and I didn't see enough difference from last time to say it helped. NASA Road America is this weekend, I'll be sure to inspect any data to see if there is a benefit.
Racer
Joined: Sep 2010
Posts: 379
Likes: 0
From: Kingsland GA
[QUOTE=killergsxr1;1581974691]hi guys,new around here,since nobody makes aftermarket support for us c4 guys i thought i would try helping us out.
Yes. I used to complain about the lack of support for C4 products. Then I designed some products at great financial expense. In the end, C4 owners don't seem to desire the aftermarket products that civics, mustangs and other mid priced cars enjoy. I was even considering making several additional products for C4s after my headlight design, but based on feedback, I may cater to C5s.
Yes. I used to complain about the lack of support for C4 products. Then I designed some products at great financial expense. In the end, C4 owners don't seem to desire the aftermarket products that civics, mustangs and other mid priced cars enjoy. I was even considering making several additional products for C4s after my headlight design, but based on feedback, I may cater to C5s.
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Burning Brakes
Joined: Jul 2012
Posts: 826
Likes: 3
From: Seabeck WA
In order to make downforce the diffuser has to start around the middle of the car, or at least in front of the differential, and then gradually open up to the back. While they will keep air from building up inside the bumper, they are not performing the functions of a diffuser to make downforce.
Race teams spend thousands of dollars, and tremendous amounts of time to get the angle right, fin size and locations, etc. etc. Without that knowledge you may actually hurt the aero balance of the car by guessing.
Race teams spend thousands of dollars, and tremendous amounts of time to get the angle right, fin size and locations, etc. etc. Without that knowledge you may actually hurt the aero balance of the car by guessing.
Yep. This goes along with everything I've read while doing my own researching on diffusers.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
I'm not sure what I'm missing here, but all I see is a shadow.
Le Mans Master
Joined: Oct 2007
Posts: 9,685
Likes: 3,437
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
Kubs, I was wondering if I would see any difference at the drag track with my plate on there. I trapped almost 117 and I didn't see enough difference from last time to say it helped. NASA Road America is this weekend, I'll be sure to inspect any data to see if there is a benefit.
Thread Starter
3rd Gear
Joined: Oct 2012
Posts: 3
Likes: 3
From: tucson arizona
heres a pic of it coated,there are mounting brackets that arent pictured but i wanted to give you all a look at what it looks like out of the car
i think i will be making a version for use with the spare tire and a version without
i think i will be making a version for use with the spare tire and a version without
Racer
Joined: Jul 2004
Posts: 434
Likes: 0
From: Santa Barbara Minnesota
Aero Improvements'
hi guys,new around here,since nobody makes aftermarket support for us c4 guys i thought i would try helping us out.i have many plans i will make but the first project is a rear diffuser for the c4..i already have one on my car and it looks great..right now i have very limited pictures but im getting more for you guys..how many of us c4 guys would be interested in something like this???? heres just a tease