PPF CS trunk spoiler and front lip

05-09-2026

I had a CS spoiler, CS front lip and OEM diffuser installed on my f82 m4.

I took the car to my ppf guy and he had a difficult time installing PPF on these parts. I noticed he was struggling to install on the following areas:
1. On the rear spoiler due to the dip in the middle of the spoiler
2. All the curves on the front lip
3. The fins on the rear diffuser

Does anyone have any tips on how to best install PPF on these parts?

Looking for maybe a template or how many pieces it took, cuts. etc.

05-10-2026

I rebuilt my CS spoiler due to damage. I did the carbon fiber repair but not the PPF but it cam out as good as knew so it's possable
Before
An image attached to this post, provided by the poster

An image attached to this post, provided by the poster

After

05-10-2026

Looks great. Did you strip off the clear coat with sand paper and then spray with clear coat?

How are you finding the Sliplo, is it effecting in protecting the lip?

05-10-2026

I only posted one before picture but the damage was extensive. I just roughed the surface and I did my repairs with sanding and resin. I recreated the Carbon Fiber look with paint and tooth picks on badly damaged sections.
Here is one trick I learned. A hex drill bit will remove the stone chip damage and leave good edges. Fill dimple with resin, sand.
An image attached to this post, provided by the poster

I didn't finish with resin top coat as it's too complicated a shape. I used sandpaper from 400 working to 3000. I compounded and polished before taking it to the PPF installer
The Sliplo's are holding up great but they do remove a little of the already limited ground clearance.

05-10-2026

Hopefully the PPF keeps it more protected going forward. You did such an amazing job it would be annoying to have to do it again but sounds like a fun project.

I'll keep that trick in mind, when getting my windshield repaired the guy does the same thing, drill and then fill.

What resin did you use?

400 to 3000, is 400 too coarse or is it a good starting point? I watched some videos of cf repair and was concerned that 400 would take off too much but I am a complete newbie when it comes to this stuff so I don't know anything.

Hilarious profile photo btw

05-10-2026

I don't want to do it again. :sigh:

I wanted to keep the car OEM or I would just have ordered a $1200.00 knock off. The culprit is trailering the car, it is hell on spoilers and I'm done with that.

I didn't figure out the drill and fill until I was under the gun to keep my appointment with the PPF installer. For stone chips, you can't beat it. The white that shows is damaged resin not the carbon fiber. Get rid of the white and fill and then do standard paint correction technique.

As for Sand paper, like paint correction anything you do you have to fix. :sigh:

If you can get the surface repaired with 600 then that what I would start with.

My damage was 400 level damage :sigh:

I used standard over the counter resin and hardener.

05-12-2026

It's to be expected with a front lip but we will see how bad it gets. I was thinking buy a cheap CS lip to see what happens and if all is good and it doesn't get completely destroyed then I might upgrade to a nicer one down the line.

I remember driving around San Francisco and it was a complete nightmare. Can't image how it would be with a lip.

I think the best we can do is PPF the lip, stick on Slip Lo underneath and hit the bumps and ramps at an angle.

I noticed you also only stick one row of the Slip Lo on your bumper. Do you think it would make a difference attaching multiple rows to basically cover up the whole bottom of the lip like how they have it in the marketing photos. Obviously they want you to do that to well more product but I can see putting some on the rear of the lip helping

05-12-2026

ABCDEFG111 wrote
It's to be expected with a front lip but we will see how bad it gets. I was thinking buy a cheap CS lip to see what happens and if all is good and it doesn't get completely destroyed then I might upgrade to a nicer one down the line.

Some of the non-OEM spoilers are really good and if it wasn't my desire to keep the car original I would go that way. Also the OEM CS spoiler has a unique mounting kit and when I checked the were unobtainium.

ABCDEFG111 wrote
I remember driving around San Francisco and it was a complete nightmare. Can't image how it would be with a lip.

Mine hits a lot more than I would want. Lots of slow angle entries in my future:D

ABCDEFG111 wrote
I noticed you also only stick one row of the Slip Lo on your bumper. Do you think it would make a difference attaching multiple rows to basically cover up the whole bottom of the lip like how they have it in the marketing photos. Obviously they want you to do that to well more product but I can see putting some on the rear of the lip helping

No if it going to hit the row I have the second row won't help IMO.

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PPF CS trunk spoiler and front lip