C5 Rear diffuser making progress
Thread Starter
Drifting
Joined: Mar 2012
Posts: 1,517
Likes: 147
From: Jasper Alabama
Update. I am extending the fins about 2.5". This brings them flush with the lower edge of the exhaust tips. Since I have a few weeks to play with I am working on a detachable under pan. This will be removable for any maintenance issues. Will blend in with the diffuser when mounted and look as if it was one piece.
Thread Starter
Drifting
Joined: Mar 2012
Posts: 1,517
Likes: 147
From: Jasper Alabama
Well I've added some extensions to the fins this evening. Had to wait for another C6 diffuser to get here so I cut it up and get the pieces needed to extend the fins with the proper curves and angles. I will post pics tomorrow. Let me know what you think before I bond them on permanent.
Thread Starter
Drifting
Joined: Mar 2012
Posts: 1,517
Likes: 147
From: Jasper Alabama
Ok here are some before and after pics of the fins. Bare with me as I try to upload them in sequence so you can see the difference. Please give me your feed back as I will decide to add them permanently or not.
Before
After
Different view Before
After
Another Before
After
Before
After
Different view Before
After
Another Before
After
Last edited by Stealth02; Apr 24, 2015 at 01:51 PM.
Racer
Joined: Mar 2012
Posts: 272
Likes: 388
From: SWFL
2026 Corvette of the Year Finalist - Modified
2025 C5 of the Year Winner - Modified
2024 C5 of the Year Finalist - Modified
I like it. The outer "fins" being curved instead of angular look much better in my opinion.
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Le Mans Master
Joined: Jul 2007
Posts: 6,094
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From: Oswego IL
Reeeeally liking how the second version is turning out! Much more aggressive, and doesn't just look like a C6 diffuser. Will match up well with any added side skirts and front lip, now that the height of the diffuser is lower! Keep up the great work! 
Drifting
Joined: Oct 2008
Posts: 1,595
Likes: 191
From: Wilmington DE
Acct Suspended APR 2026 by request
Joined: Dec 2010
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2020 Corvette of the Year Finalist (performance mods)
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I liked it better before and rounded edges might look better in my opinion... the sharp edges and bigger fins just don't fit with the rest of the c5 body style and it sticks out like a sore thumb
Melting Slicks
Joined: Jul 2004
Posts: 3,092
Likes: 120
From: orlando florida
St. Jude Donor '15
found a shop here in florida that supposedly makes one
This is a 100% functional lower rear diffuser. A must for track days or that ultimate racing look. Bolts on in about 1 hour.
Weight is under 10lbs.
It is a easy bolt on. Trim of the lower factory bumper and our rear diffuser bolts in from the back side and has a brace and bracket that attaches to the lower control arm bolt.
Our Diffuser was designed around the B&B 2 tip Exhaust system but other 2 tip systems could work as well.
This is a 100% functional lower rear diffuser. A must for track days or that ultimate racing look. Bolts on in about 1 hour.
Weight is under 10lbs.
It is a easy bolt on. Trim of the lower factory bumper and our rear diffuser bolts in from the back side and has a brace and bracket that attaches to the lower control arm bolt.
Our Diffuser was designed around the B&B 2 tip Exhaust system but other 2 tip systems could work as well.
Thread Starter
Drifting
Joined: Mar 2012
Posts: 1,517
Likes: 147
From: Jasper Alabama
found a shop here in florida that supposedly makes one
This is a 100% functional lower rear diffuser. A must for track days or that ultimate racing look. Bolts on in about 1 hour.
Weight is under 10lbs.
It is a easy bolt on. Trim of the lower factory bumper and our rear diffuser bolts in from the back side and has a brace and bracket that attaches to the lower control arm bolt.
Our Diffuser was designed around the B&B 2 tip Exhaust system but other 2 tip systems could work as well.
This is a 100% functional lower rear diffuser. A must for track days or that ultimate racing look. Bolts on in about 1 hour.
Weight is under 10lbs.
It is a easy bolt on. Trim of the lower factory bumper and our rear diffuser bolts in from the back side and has a brace and bracket that attaches to the lower control arm bolt.
Our Diffuser was designed around the B&B 2 tip Exhaust system but other 2 tip systems could work as well.
Last edited by Stealth02; Apr 25, 2015 at 06:40 PM.
Drifting
Joined: Oct 2008
Posts: 1,595
Likes: 191
From: Wilmington DE
That Breathless has been out for a while and I think most agree its fugly and sticks out like a sore thumb. So hoping the OP of this thread doesn't go too far with adding extentions or may end up looking like the breathless one. Keeping it smooth with the lines of the C5 is the way to go.