Rear Diffuser install PIC HEAVY!
#1
Burning Brakes
Thread Starter
Rear Diffuser install PIC HEAVY!
Hello all just thought I would share my experience with installing the rear diffuser on my Vette. So here we go.
First thing I did was take some 100 grit sanding paper to all the contact areas for the double sided tape and the heat shielding tape in the muffler area. Just to rough it up a bit because the finish is pretty slick on the inside of the diffuser. Also wipe all sanded areas clean with alcohol afterwards.
For the double sided mounting tape I used 2 layers as the 3M tape just isn’t thick enough to make contact with the bumper after you bolt it on.
Next I had to remove the mufflers and as you can see I have the massive Magnaflow and they will fit under the diffuser with a little trick.
Went to the store and found 2 bolts that are 1" for the 2 outside mounting holes as the 3/4" bolts that came with it didn't reach far enough to thread in for me. With that added 1/4" it was very easy. (Make sure to clean the mounting area on the bumper for the double sided tape before bolting up.)
Drilled the 4 holes per directions when lined up. As far as the factory center bumper retainers go I absolutely could not get those to go back in after mounting the diffuser so I found some 10mm threaded bolts and threaded them into the 4 holes ( I really don't recommend this but it's the only thing I could get to work.)
If you have a large muffler set up like I do you will have to line up and tighten down the 4 main mounting bolts that go through the vents in the bumper as they will NOT be accessible after you put the mufflers in place. Now is a good time for the center retainers if you can get them to work or the center bolts like I had to. The 2 forward side screws can still be reached afterwards though.
I had to unbolt the exhaust pipes at the transaxle so that I could fit the mufflers inside the diffuser once bolted on otherwise I could not fit them in. Taking off the rear wheels helps with a lot more room for the big *** mufflers.
Here are the mufflers crammed into place and the pipes reattached. Yes they make contact with the diffuser.
For the 2 forward side attach screws I would highly recommend going to the hardware store and picking up these little brackets for a few dollars as they work 100 times better than the washers in the kit for holding the front to the bumper.
After everything is lined up and tight peel the ribbon off the mounting tape and then to aid in the tape sticking to the bumper I used blue tape to keep pressure on the diffuser for an hour or 2.
After 1,000 miles on the Hot Rod Power Tour everything is still in place!
Enjoy!
First thing I did was take some 100 grit sanding paper to all the contact areas for the double sided tape and the heat shielding tape in the muffler area. Just to rough it up a bit because the finish is pretty slick on the inside of the diffuser. Also wipe all sanded areas clean with alcohol afterwards.
For the double sided mounting tape I used 2 layers as the 3M tape just isn’t thick enough to make contact with the bumper after you bolt it on.
Next I had to remove the mufflers and as you can see I have the massive Magnaflow and they will fit under the diffuser with a little trick.
Went to the store and found 2 bolts that are 1" for the 2 outside mounting holes as the 3/4" bolts that came with it didn't reach far enough to thread in for me. With that added 1/4" it was very easy. (Make sure to clean the mounting area on the bumper for the double sided tape before bolting up.)
Drilled the 4 holes per directions when lined up. As far as the factory center bumper retainers go I absolutely could not get those to go back in after mounting the diffuser so I found some 10mm threaded bolts and threaded them into the 4 holes ( I really don't recommend this but it's the only thing I could get to work.)
If you have a large muffler set up like I do you will have to line up and tighten down the 4 main mounting bolts that go through the vents in the bumper as they will NOT be accessible after you put the mufflers in place. Now is a good time for the center retainers if you can get them to work or the center bolts like I had to. The 2 forward side screws can still be reached afterwards though.
I had to unbolt the exhaust pipes at the transaxle so that I could fit the mufflers inside the diffuser once bolted on otherwise I could not fit them in. Taking off the rear wheels helps with a lot more room for the big *** mufflers.
Here are the mufflers crammed into place and the pipes reattached. Yes they make contact with the diffuser.
For the 2 forward side attach screws I would highly recommend going to the hardware store and picking up these little brackets for a few dollars as they work 100 times better than the washers in the kit for holding the front to the bumper.
After everything is lined up and tight peel the ribbon off the mounting tape and then to aid in the tape sticking to the bumper I used blue tape to keep pressure on the diffuser for an hour or 2.
After 1,000 miles on the Hot Rod Power Tour everything is still in place!
Enjoy!
The following users liked this post:
lewislgZ06 (06-22-2016)
#2
Hmmmm, glad you like it. As for me, I'm not convinced.
It looks too aggressive for the lines of the car. And the gap makes it look like something "stuck on", and is about to fall off the car. Just my opinion......
Anyhoo, like I said, it's all about YOU.....
Shakey
It looks too aggressive for the lines of the car. And the gap makes it look like something "stuck on", and is about to fall off the car. Just my opinion......
Anyhoo, like I said, it's all about YOU.....
Shakey
#3
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Awesome write up, pics, and instructions. Thank you for taking the time to share.
Your car looks great with this mod!
Your car looks great with this mod!
#4
Le Mans Master
Not my taste but looks like a clean install.
#5
That came out nicely! We think it looks great paired with our system!
#9
Burning Brakes
....That's the beauty of doing mods, some will like it, and some will not !! I personally don't think that this diffuser is aggressive at all, kinda tame, but to each their own. I will say that I agree with others to some degree that it would work better with other elements added to the car to complete a theme. Good work, keep on having fun !!...
#10
Burning Brakes
Thread Starter
Thanks for the positive feedback guys, I like the way it looks but I dunno there are only so many things you can do with a C5 body wise. Figured I would try this for a break from the same old stuff and it's easy to remove if I get tired of it, as you don't have to drill the stock bumper at all for install.
#11
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Thanks for the write-up. The diffuser looks good on the car.
#14
Instructor
I think you might run into heat issues with the diffuser riding againt the muffler? The factory bumper is vented for aero and heat loss
Last edited by 0260N5; 06-22-2016 at 09:56 PM.
The following users liked this post:
caddman11 (06-22-2016)
#15
Burning Brakes
Thread Starter
It does sag down just a little bit in the middle of the area touching the muffler from the heat and wind pulling on it. Would be nice if they would build them with a little renforcement in that area. Just a thin metal rod or strap molded in that area would be enough to keep it from sagging. I may look into fitting a strap of some sort in there.
#17
Racer
Man I was excited when I saw this. I really wanted to like it, but I agree with the few guys in here commenting that it needs more. It stands out enough to really need a whole kit or something else to make it look like it fits in. Side skirts would possibly help off set it a little. It could also be that it's a dark diffuser on a car colored car. I'm willing to bet it would probably pop differently on a red or yellow vette. I painted the bottom area of my Z06 to set it off and I think it looks clean (Millennium Yellow).
I'm not saying it looks bad, just that it looks a little out of place and maybe needs to be part of a whole kit or something to balance it out.
That exhaust sitting on it worries me too. I'd hate to spend a chunk of change on a body piece only to have it melt.
I'm not saying it looks bad, just that it looks a little out of place and maybe needs to be part of a whole kit or something to balance it out.
That exhaust sitting on it worries me too. I'd hate to spend a chunk of change on a body piece only to have it melt.
#18
It does sag down just a little bit in the middle of the area touching the muffler from the heat and wind pulling on it. Would be nice if they would build them with a little renforcement in that area. Just a thin metal rod or strap molded in that area would be enough to keep it from sagging. I may look into fitting a strap of some sort in there.
#19
Drifting
If it was mine I would find a way to vent it like the factory bumper. Regardless of functionality it looks better than a oem bumper in my opinion. There are countless people that put things on there car that have no function at all where diffusers are supposed to aid aerodynamics.
#20
Drifting
I was big supporter of having this made. With that said after looking at it does stand out a bit. I think an upper spoiler is needed to balance it out. A SLP or Carrivaggio style would flow best with the curves. Side skirts and a front lip would help too when looking at the car as a whole