Calling all you owners with spoilers

[Mal CSL 3.0]

Really need some advice here as facing a bit of a dilemma.

I have had my car in getting a boot repaint and a small spoiler installed. (I managed to acquire an original CSL spoiler, this spoiler is not a recent repo version)

When I briefed the body shop I wanted the spoiler flush with the boot-lid however the reality is the curvature on the spoiler is slightly more of a rounded arc so sits about 6mm proud of the metal on edge of boot-lid in middle section. (the corners match but it bows out ever so slightly in the middle section)

I have looked at many photos of other cars, some spoiler installs also have a slight 'overbite' vs the rear lower centre panel, yet I have also seen other spoiler installs where they seem to make the spoiler perfectly follow the curvature of the boot-lid and flush with panel below.

I really need advice as I was hoping to pick up my car today all done. The body shop is very accommodating so would be willing to take off the spoiler and try to fettle around more, but it is already mounted (so hassle to get off) and no guarantees it can be made to sit flush the way I hoped, as with a wider arc on the spoiler it may be impossible ..... Could be opening pandoras box to try.

Anyway just wondering what I should do - just be happy with a slight 'overbite' as per the photos or should I keep pushing to get perfectly flush and flat, which might also be impossible.

Most important question is what would they have looked like when installed from 1970's era? If anyone has an original spoiler on their car, I would love to see how it sits.

(PS On the bright side they did lovely paintwork. Badge and decal going on soon)

My car below:

Here is 2 examples with the overbite:

No overbites

 

[Markos]

Not a CSL owner. I can find anything on the internet though.

1974 brochure:

 

[Mal CSL 3.0]

Not a CSL owner. I can find anything on the internet though.

1974 brochure:

I thought e9coupe is the internet Anyway I did look at your picture in my CSL brochure before posting, and actually the rubber droops in the middle and the panel gaps are not 100% even, so maybe could be that the middle of the spoiler bows out slightly.

This car from the BMW museum also seems to have slightly more curvature in the spoiler as it sits out a fraction. The shadow line denotes that imo.

We managed to improve mine a bit - see below. I would have to grind away at my original CSL spoiler and reform it to make it fit even more precisely. So maybe not worth the hassle.

(I also kindly just got sent a photo of my actual spoiler from the seller when it was on his CSL many years ago. It also didn't sit precisely either)

 

[HB Chris]

I think it looks perfect just the way it is, what a stunning CSL.

 

[Keshav]

This car from the BMW museum also seems to have slightly more curvature in the spoiler as it sits out a fraction

Mal,
Although not relevant to your topic, that Türkis Csl is not from the BMW museum, rather a private owner in Germany.

 

[burky]

Hullo Mal
These spoilers are not precision pieces, I would go so far as to say that if you laid out a dozen spoilers side by side there would be differences in all of them, because of the material they are constructed, of and the age.
I had a good look at my spoiler , which is off the car , and the lower edge of the vertical plane is quite uneven , sagging in the middle and the entire length is not uniform , fiberglass! . The lower edge can be sanded to suit the lower edge of the boot lid , the danger there is that you go through the gel- coat and expose to much of the fiber , you can also go the other route build up the low sections of the edge with fiberglass resin to achieve the edge that you are looking for.
You have a beautiful car, the paint looks great , after a while that minor difference will just blend in and disappear.

 

[m73]

Enzo is watching.....

Looks pretty good IMHO

 

[Drew20]

Your car looks awesome, I wouldn't sweat it.
My car has the spoiler. Not sure it was fitted in the factory, but was defo on the car by the early 80s. It does look to fit flush all the way across, but on closer inspection it's not hugely tidy! Let me know if you want any more shots, but as I said, I wouldn't change a thing

 

[Mal CSL 3.0]

Many thanks Drew, appreciate you sharing your photos.

Yes I think the flush fit is the way they are meant to be. Luckily mine fits perfectly along the bottom edge, it just sits out about 6mm too much in the middle as the spoiler curvature is not the same as the boot-lid.

Anyway most people probably wouldn't notice, as much as I do.

 

[Rob F]

The rear spoiler does give the car that sporty edge, Does anyone have a duck tail spoiler going spare they are willing to sell as i'm on the look out for one
regards
Rob

 

[Keshav]

The rear spoiler does give the car that sporty edge, Does anyone have a duck tail spoiler going spare they are willing to sell as i'm on the look out for one
regards
Rob

@daddywad (UK) has new (repros) ones with the rubberlip, the only one ww (with the rubber lip) as far as I know.

Keshav

 

[Rob F]

Thanks Keshav, I’ll give daddywad a call

 

[HB Chris]

Just saw the former Paul Cain coupe, it has the same center overbite, no big deal.

 

[Arde]

Invisalign?
Anyway I am not an owner with a spoiler, I am just a spoiler.
I think the trunk lid spoiler transforms the visuals of the car, looks great.

Just saw the former Paul Cain coupe, it has the same center overbite, no big deal.

 

[Honolulu]

A neighbor tried several times to create a fiberglass hood for his '55 Chevy. It warped each time - suggesting that "all" glass items have the capacity to do so.

I used to do a bit of work (a lot, now that I think of it) with glass. Polyester resin (the most common) has is a considerable amount of styrene solvent in the product, much of which evaporates. I think this may largely be the cause of warp and thus as Burky points out in post 6 above, they're going to sag, bend, twist, warp etc., particularly if left out in heat and sun in every fabrication unless very carefully planned, laid up, cured and used.

At this point it's it's your time and money if you want a closely fitting spoiler, modifying a rare and beautiful piece.

IIRC also, early M6s had issues with their spoilers - when one closed the trunk lid and there was contact, the paint would suffer. A gap is preferable between the spoiler edge and the fender (or quarter panel or whatever else you may call it). A solution common in those days was some clear tape at the contact area.

 

[Mal CSL 3.0]

Yes Honolulu an excellent point you make - if the spoiler is not sitting slightly outwards, there would be a high potential to strike the steel body panel below when shutting the boot, and yes fiberglass would be very prone to cracking.

Picked up my car on Tuesday and took some photos on the way home. 100% the spoiler has made it look so much better. If an E9 has all the appendages such as roof hoop, bumper delete, front spoiler and wind splitters, it really needs the rear spoiler to make it look properly 'balanced'.