BMW M3 (E30 M3 | E36 M3 | E46 M3 | E92 M3 | F80/X)

BMW M3 (E30 M3 | E36 M3 | E46 M3 | E92 M3 | F80/X) (
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-   -   CSL Front Bumper Group-Buy (

Dr M3an M3 Wed, Apr-05-2017 02:23:32 AM

CSL Front Bumper Group-Buy
Streamline CSL Front Bumper Group-Buy

Now that we are winding down the first round of this Group-Buy (GB), it is finally time that I update this OP as we continue to move forward and plan for a second round of this GB.

If you would like to order a bumper (either as part of this GB or independent of the GB, please send me a PM or send me an email to:
*If you are reading this, then yes, you we are still taking on orders for all of our products.

Details about this CSL-Clone Front Bumper:

High-quality CSL replica bumper for the e46 m3 from either FRP or Carbon Fiber composite. The bumper features a four-layer structural brace integrated within its construction. The brace is made from a mesh of carbon-kevlar and fiberglass for the FRP model or BI-axial carbon fiber for the carbon fiber model. The bumper has side fender mounts and comes with a set of 1x1 or 2x2 lacquered carbon fiber splitters matched specifically to that bumper. Mounting requires the bumper-shocks from any e46 other than the M3. The bumper has a plank for the OEM M3 washer-bottle used with the OEM KEVLAR brace. Bumper arrives fully PRIMED for the FRP variant and fully Lacquered for the carbon variant. *Price does not include front grill, or intake grill. The OEM ones can be used/reused*

Recent changes that have been made or in the process of being implemented for the CSL Bumper:
-Fully redesigned mold made with higher quality resins and gel-coats.
-New AERO grade resin used for FRP Bumpers
-Modified splitter option - more aggressive splitters available similar to the CSL Concept car
-Multiple Molds recreated for quicker creation times
-Stainless Steel windshield washer bottle plank instead of normal steel (fits both stock and CSL washer bottle)
-Nuts for bumper holders will be placed further back, so that US and EU bumper holders work without an issue.
-Bumper Brace will be made from Carbon Fiber and Carbon-Kevlar composites, without FRP making the brace stronger, thinner and lighter
-2 Year Warranty will be added to the item :thumbsup2:
-Full prep of the item is added, so item arrives fully prepped for detailing
-Resin is updated for Carbon Items as well
-Vacuum technology and creation methods are updates for higher quality items.
-Every item will be baked for 2-3 hours after creation
-Product number, code, material, date of creation included under the resin on inside of item

Weight FRP: 4.5kg
Weight Carbon: ~2kg

Weight savings FRP: ~ 6-7 kg
Weight Savings Carbon: ~ 8.5-10kg

Will these bumpers allow the use of other manufacturer's CF front splitters, in the event that I ever need to replace them?
YES Any other oem replica splitter will fit 100%. You can even buy an OE Splitter and it will fit, so no worries about that! This bumper was designed like this on purpose. If you ever need to replace a splitter, your hands are not tied solely to this manufacturer. They do offer replacement CF splitters though.

Will there be an option for a 1-piece lip instead of the splitters?
At this time, the company does not have anything in the works regarding the production of a 1-piece spitter. This may be a possibility in the future, but at this time a 1-piece lip is not something we are offering. We believe that form follows function and thus we chose to stick with BMW's purposefully engineered splitter system.
A lot of people think that the CSL splitters are purely visual, BUT the reality is that it tremendously reduces front-end lift over the front axel (the CSL splitters provide an 83% reduction in front end lift over the standard M3). —> That is HUGE!


Some rare wind tunnel testing:
E46 M3
Frontal Area: 2.07 m(squared)
Drag Coefficient: 0.32
Front Axle Lift: 6kg
Rear Axle Lift: 18kg

E46 M3 CSL
Frontal Area: 2.07 m(squared)
Drag Coefficient: 0.33
Front Axle Lift: 1kg
Rear Axle Lift: 10kg
Will a dual-intake hole bumper be an option?
No. Unfortunately not, they are sticking to making only the single-intake hole bumper, like the OE CSL bumpers.

How does it attach to the car?
-This bumper does NOT require an aluminum bumper support like other reps. it uses the exact same mounting system that the CSL bumper uses. Namely #9, 10, and 11 from realoem, as the bumper carrier is built in to the bumper itself, like the original. Should be considerably lighter for you if your car currently uses the aluminum carrier!



I know many have asked that. We know some of our competitors have made bumpers, where you just stick the grill to the bumper, which is also a variant. However, if someone wants to change their front grill for example, or maybe add a supercharger and the grill is in the way of the intercooler, or any other scenario, where one might need to take it off - we needed a solution. Adding the OEM tabs from FRP and Carbon is impossible. Simply because the materials would not allow us to add these elements safely and for it to look good, we would have needed to rework the whole mold. What we did however, is work with what we had.

On the pic bellow you are seeing our solution. With every bumper you will recieve a set of 8 bolts / screws (not sure what they are called in english). Every bumper will have tabs which are marked in purple on the diagram. They sit effectively behind the grill. Through the marked holes on the OEM grill every user can screw in his front grill. This way you will not need to stick the grill to the bumper. If you do however want to do so, you can do that too! This was the best workaround, seemless integration we were able to come up with, and I really hope you like it. A lot of thought has gone into these bumpers as you probably already know.
Installation-Guide Video:
*PLEASE NOTE: In order to insert the bumper shocks into the bumper you will need to use an Allen Bolt Key on the bottom of the shock in order to retract the threading. Once the bumper shock is inserted into the bumper, then screw the threading back out again and insert the asa bolt. Finely adjust for fitment on both sides.

Is this the same bumper that other car part distributors sell? You know the "EuroSpec" bumper? ...and Is this going to have that inflated "chipmunk cheek" look to it?
Nope. Completely different bumper, 100% hand-made in house in Europe. These bumpers have not been released yet. Nothing will leave the manufacturer if the weave, quality, and fitment are not 100%.

Let's see some pictures!

Full Carbon CSL Bumper -- 2x2 weave, which matches up perfectly with the direction of the 2x2 CF CSL Splitters:

Full Carbon CSL Bumper painted Alpine White with exposed carbon intake hole and 2x2 CF Splitters:

In-house painted Imola Red FRP CSL Bumper with 1x1 CF CSL Splitters AND In-house painted Mystic Blue FRP CSL Bumper with 1x1 CF CSL Splitters:

In-house painted Imola Red FRP CSL Bumper with 1x1 CF CSL Splitters:

In-house painted Interlagos Blue CSL bumper with 1x1 CF CSL Splitters

In-house painted Carbon-Black CSL Bumper w/ 1x1 CF CSL Splitters

A short video of the bumper: :thumbsup2:

Close up video of our Carbon Splitters:

Splitters Fitment Video:

Some unpainted FRP CSL Bumpers as well as various pictures of both our 1x1 and 2x2 Carbon CSL Splitters:

In-house painted LSB Bumper with 1x1 CF CSL Splitters:

(Splitters are resting in place to show both pieces fitting together.)

Fitment Pictures:
ksa74f's Bumper:[/QUOTE]

Gearhead55's Bumper:

Other products that we make, which can be combined with your order:
-Full Carbon and FRP Fenders (OE style and vented)
-Full Carbon and FRP CSL Bootlid
-Full Carbon CSL Diffuser
-Full Carbon CSL Roof
-Full Carbon CSL Airbox --> Soon-to-be released!

Carbon Roofs:

CSL Bootlids (Full Carbon and FRP):
Post-Install of Streamline CSL Bootlid -- Customer Review:
Another happy Streamline customer! :thumbsup2::parrot:

Full Carbon CSL Diffusers:

Full Carbon Fenders (OE-Style and Vented):

Information about our design and material considerations -- The Technical details:
Update 4/6/17:

Originally Posted by Bubblegunz (Post 1067627285)
Hi boyz,

I am Antony, the CEO of Streamline and I am here to give your minds a little bit of rest on the matters. This will be the only time I will schime in, because there is a lot of 3rd party info, going from 1 guy to the other and I would prefer for me to answer everything directly. I will try to be as theral as possible.

The people I work with are also creating elements for race-cars sutch as european rally-cars (where as you know nothing is left to chance and everything is tested/stress tested etc.), time-attack cars, hillclimb racers etc. The same people work at the moment for a team which has been an european hillclimb champion and has been on the european rally podium. They are currently building up the legendary audi S1 and has a lot of experience building race-cars. This means that these people know a lot more than me about what they are doing and because I want the highest quality items on the market I have these people in my team. Furthermore the exotic cars that have gone through these people's hands is insane - from the rarest possible 992 GT2 RSR to Lambo's, Porsche's etc. The point of this is not to brag, I couldn't care less about that. It is so you know that we are not just 2 people in a garage building carbon products. We are a team of people who test / create and for the most part - know what they are doing. And we are honest enough to not charge 4-5x the price of the item because we can...

Enough about us, I will begin by explaining each material as therally as I can by refering to its properties.

There is a huge misconception that Carbon is a "stronger" material than fiberglass. If you google the word "strength" this is what comes up:

"the strength of a material is its ability to withstand an applied load without failure or plastic deformation"

What will be a huge surprise to many people is that Fiberglass can withstand a higher ammount of load per area than carbon fiber - meaning it has a higher tensile strength. The highest quality fiberglass has about 35-40% higher strength properties than carbon for the same ammount of force applied at the same area. Lower quality fiberglass has about a 15-20% higher strength properties in this regards. High grade fiberglass is actually used in spacecarft where they need high-strength material which needs to be thin at the same time.

Kevlar is on par with the lower-quality fiberglass in terms of strength, and a not as strong as the higher-quality material out there.

Comparing this to aluminium, the carbon fiber is a lot stronger as a meterial per unit of area. So is Kevlar and so is fiberglass.

Actually the tensile strength of all these materials is a lot higher than steel. Again please understand that this is PER UNIT OF AREA not per KILOGRAM so weight is not the factor here! I will get into the weight of the materials a bit further down the line :).

Okey so why are car manufacturers using CARBON rather than Fiberglass? There is a lot to the story. Talking about chassis dinamics is where it will sort of start to make sense. Further down the line I will explain the weight differences as well, which is another reason.

As I told Leighton Carbon fiber is a very very stiff material. In terms of chassis dinamics carbon is about 10% stiffer per unit of area than steel. It is why it is used by car manufacturers for chassis development - if you look at modern supercars all of them have a "carbon tub". It is why it is a great material to be used for a roof and we wouldnt sell a fiberglass roof for anything other than a race car :).
Kevlar is about as stiff per unit of area as high-grade fiberglass. Both of them are about 50% less stiff than Carbon Fiber.
Now let us get to the weights which ties to everything. Carbon is not only 10% stiffer than steel per unit of area, but it is between 60-70% lighter. This simply because the material is a lot less dense than STEEL. Which means that for the same weight as a steel chassis your chassis will be about 72-75% stiffer and more durable (because when you go from lower to higher number percentages change, I hope you realise that).

Kevlar is about a bit less dense than carbon fiber and fiberglass is about 35% denser than carbon. Which is why you see FIBERGLASS items to be about 2x the weight of carbon fiber items.

So in terms of strength to weight KEVLAR IN TENSION will be about 25% stronger and Carbon will be on PAR with high-quality fiberglass and about 10-15% stronger than low-grade fiberglass. However to achieve the same weight the item will also be about 45% bigger. As you probably realize in a front bumper we do not have the space to put 45% more material in order to make the carbon item the same tensile strength.

So for the amount of material we can put, the weight difference comes from the fact that carbon is less dense as a material, but since the same amount of material is used – the item in FRP is actually STRONGER than from carbon fiber.

SO WHY didn’t BMW just use KEVLAR for the front bumper?

Well.. what I haven’t talked about yet is trength in compression. The problem with Kevlar is is that it is creat in tension, but very very poor in compression. The fibers in Kevlar buckle at about 20% the force needed to buckle a fiberglass item OF THE SAME WEIGHT and at about 30% of the force needed to buckle a carbon fiber item of the SAME WEIGHT. So Fiberglass in compression is about 10% stronger PER UNIT OF WEIGHT than carbon fiber. What this means is that if the bumper is 2KG from fiberglass and 2KG from carbon the fiberglass bumper will be the same strength in TENSION and 10% STRONGER in compression. However the FIBERGLASS bumper will be about 2x that weight, so effectively you will have a 2x stronger bumper .

SO to answer the question – WHY DIDN’T BMW USE KEVLAR? Well if you look at your brace, it has multiple angles so that the fibers always work in tension. Not only that but the fibers are connected in different directions. What this means though is that depending where the hit comes from, (from the side for example) if the force is in exact compression to the fibers that brace will have a 50% reduced strength from that impact, because these will fail very very early and only the fibers in tension will actually transfer. It is probably why my personal Kevlar bar failed from a small hit. A FRONTAL hit will make the bar work SOLELY in compression, which is not the issue here. However to adapt the brace with the bumper they would have had to have more fibers working in compression from more angles, which means the shape of the bumper couldn’t have been as it is… it will need more angles and will need a new engineering philosophy. One other thing is that one of the creators admitted that the bumper was taken straight out of one of their motorsport cars – where carbon is mostly used. I will get back to that in a sec.


One more thing is Toughness. The toughness of a material measures its ability to resist stress and strein. Which is basically its resistance to an impact. ELONGATION is an important factor here, it basically measures how far a material can strein before it fails. Well S-glass has the highest toughness per unit of AREA. BOTH fiberglasses do, where high-grade fiberglass comes first. This is because the material has the highest STRENGTH and highest ELONGATION between all these materials. Next is Kevlar, and the least tough is Carbon Fiber, because it is a very brittle material.

In order for you guys to understand what elongation is – think of a ceramic bowl and a plastic one. When dropped (a.k.a impact) the ceramic bowl although mutch stronger will brake, whereas the plastic one may not!


BMW used carbon fiber for a couple of reasons. The main concept for the CSL was lightness (and an FRP bumper will hardly be any lighter than OEM) and CARBON for a unit of AREA is as we said a lot LIGHTER as a material. If you read the interview for pistonheads of one of the creators of the CSL car he says that he asked his supervisor whether cost is a concern or the car should be as LIGHT as possible in terms of the front bumper and the supervision said – LIGHTNESS is our biggest concern. An FRP bumper would not have been that mutch lighter than the standard one – although it would have been stronger. Also they had these bumpers made and tested for their racecars and they copied the technology without further crash-tests and other testing. IT was a more effective – lighter and somewhat cheaper and more streight forwards way to go.


The front brace is the item which took most of our time. We took appart a whole CSL bumper in order to figure out exactly how it is made. We thickened the brace a little bit as well, made it smoother. A lot of research and development went EXACTLY into that brace in order to make it the best possible product. We looked at the way it is reinforced and did the same exact thing to our bumpers. To do that you need people with a lot of experience and thankfully I have such people on my team which know a lot more about how an impact will affect the bumper then I do. We further researched the brace and as I said even thickened it at a couple of points where we thought that is needed!

The bumpers had to be out 1 month ago, however we needed 1 more month (on top of the 2 months before) for research and development SOLELY on the front brace. A test variant was made – modified, tested again, and the process was repeated until we made the final variant. It is how we work – it is what we do. After all this bumper is going on my car, and I will not risk my own life because of a bumper… especially since my car sees track duties and will see such even more often from now on – I do not have a cage installed.

P.S. One more thing I forgot to mention is that you can easily repair an FRP item with any FRP producer anywhere in the world. All you need to do is give it to them shortly after the impact and with most of the pieces that are collected. It can easily be made as good as new. Carbon is a bit different.

I hope this answers satisfies all of you guys. Sorry for my English I realize I might have made many grammatical mistakes.

Best regards,
Antony Nikolov

**Shipping Terms:
Upon Shipment of items from Streamline, once the items have been collected by the shipper, the responsibility for the items then lies with them and you as their customer. Any damage must be reported to the shipper. Any delay in delivery on grounds of transport error or damage will also be responsibility of the shipper. Myself and Streamline take no responsibility in this case.

**Please also note, ALL Streamline composite parts are 'bespoke' and hand-made to order. These are not factory assembly line produced items, and as such, when ordering a bespoke product, there is a waiting period for your item to be created after placing your order.

If you would like to order a bumper (either as part of this GB or independent of the GB, please send me a PM or send me an email to:

e46IX Wed, Apr-05-2017 02:29:27 AM

Re: FEELER thread: CSL Front Bumper Group-Buy
If you can convince them to make a 1-piece lip count me in.

Shadytype Wed, Apr-05-2017 02:42:56 AM

Re: FEELER thread: CSL Front Bumper Group-Buy
Might be an incorrect question, but I believe the aluminum front carrier is diff then the Kevlar front carrier. Will this bumper attach to both, or only one? Or do they need to specify which one we have?

daytonaviolet Wed, Apr-05-2017 02:50:13 AM

Re: FEELER thread: CSL Front Bumper Group-Buy
these bumpers look very promising. one of my main concerns are nuts for the ASA bolts attached? today streamline posted some pics. this looks like a good solution. :hattip:

terraphantm Wed, Apr-05-2017 02:58:37 AM

Re: FEELER thread: CSL Front Bumper Group-Buy
I'd only be interested if it can be made compatible with the Kevlar bumper support.

Dr M3an M3 Wed, Apr-05-2017 02:58:43 AM

Re: FEELER thread: CSL Front Bumper Group-Buy

Originally Posted by Shadytype (Post 1067626375)
Might be an incorrect question, but I believe the aluminum front carrier is diff then the Kevlar front carrier. Will this bumper attach to both, or only one? Or do they need to specify which one we have?

When I asked them this question yesterday (knowing it would come up) I was told: "It will not fit any of the 2 bumper carriers. It fits the same as the OE CSL Bumper, so the mounting mechanism utilizes the following: Number 9,10,11 on the REALOEM diagram."
(Diagram linked below)

Neither the Aluminum bumper carrier or the kevlar bumper carrier is necessary. Which means more front end weight savings (if you have the aluminum bumper carrier currently on your car)! The bumper carrier is integrated into the CSL bumper itself, just like the OE CSL Bumper. It attaches using left and right bumper shock absorbers (Those with Aluminum bumper carriers have this on their cars already, those with kevlar bumpers would need to buy them.)
~$92 each:


CSL Front Bumper Diagram:

terraphantm Wed, Apr-05-2017 03:04:21 AM

Re: FEELER thread: CSL Front Bumper Group-Buy
CSL bumper attaches directly to #9. It would be a weight savings for aluminum support cars (which have the aluminum support attaching to #9, and bumper cover attaching to the aluminum support).

The kevlar support eliminates #9, so I don't think the CSL bumper would save any weight for those cars. Might even add a little.

Also if they're going for a direct mount, I don't think fiberglass is a good idea - it would be destroyed before dissipating any energy to #9. Frankly I don't know if I would trust a non-OE engineered bumper of any material if it's performing an actual safety function (which it would be if the aluminum or kevlar bars are eliminated).

Dr M3an M3 Wed, Apr-05-2017 03:10:48 AM

Re: FEELER thread: CSL Front Bumper Group-Buy

Originally Posted by terraphantm (Post 1067626396)
CSL bumper attaches directly to #9. It would be a weight savings for aluminum support cars (which have the aluminum support attaching to #9, and bumper cover attaching to the aluminum support).

The kevlar support eliminates #9, so I don't think the CSL bumper would save any weight for those cars. Might even add a little.

Also if they're going for a direct mount, I don't think fiberglass is a good idea - it would be destroyed before dissipating any energy to #9. Frankly I don't know if I would trust a non-OE engineered CF bumper if it's performing an actual safety function.

Thanks for the clarification Terra. All valid points.

KoukiMonster Wed, Apr-05-2017 03:27:45 AM

Re: FEELER thread: CSL Front Bumper Group-Buy
I'm in. Just tell me when and where to pay. :hattip:

daytonaviolet Wed, Apr-05-2017 03:30:10 AM

FEELER thread: CSL Front Bumper Group-Buy
I agree .. that's why I have Oem csl bumper where the entire bumper and carrier is made from CF. but even with that, not sure that a CF carrier can withstand as much force as aluminum carrier even with the same bumper shocks.

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