Carbon Fiber Front Reinforcement Panel

[PurelliCondoms]

Any pics of your track car? Did you ended up doing a full cage? I remember I sold you one of my roll bar kit back in the RIP M3forum.net days

Hey man! Yes I did end up doing a full cage, she’s full race car now. Here’s a couple pics!

[Gt4]

[QUOTE=PurelliCondoms;n196468]

This is the neat part of composites...you can target reinforcement and change the properties by using different weights and weaves of fabric.

On the bottom of my splitter...I laid up strips of unidirectional tape front to rear under the bottom layer to provide more stiffness in that direction only. Again, twice as stiff as using a twill weave and less epoxy consumption. I believe this to better optimize weight vs using more layers over the entire splitter or bolting on aluminum L channel.

So I would like to apply this targeted reinforcement to the front plate. Any input is welcome!

I think the best idea for rigidity without sacrificing weight is to scallop those areas and create tunnels. Much like the one pictured here. Not only do you get an aerodynamic advantage creating a low pressure zone in the wheel arch, but it also increases stiffness. Too many benefits to pass up there.

Any pics of your track car? Did you ended up doing a full cage? I remember I sold you one of my roll bar kit back in the RIP M3forum.net days

[PurelliCondoms]

[QUOTE=bigjae46;n196444]This is the neat part of composites...you can target reinforcement and change the properties by using different weights and weaves of fabric.

On the bottom of my splitter...I laid up strips of unidirectional tape front to rear under the bottom layer to provide more stiffness in that direction only. Again, twice as stiff as using a twill weave and less epoxy consumption. I believe this to better optimize weight vs using more layers over the entire splitter or bolting on aluminum L channel.

So I would like to apply this targeted reinforcement to the front plate. Any input is welcome!

I think the best idea for rigidity without sacrificing weight is to scallop those areas and create tunnels. Much like the one pictured here. Not only do you get an aerodynamic advantage creating a low pressure zone in the wheel arch, but it also increases stiffness. Too many benefits to pass up there.

[bigjae46]

This is the neat part of composites...you can target reinforcement and change the properties by using different weights and weaves of fabric.

On the bottom of my splitter...I laid up strips of unidirectional tape front to rear under the bottom layer to provide more stiffness in that direction only. Again, twice as stiff as using a twill weave and less epoxy consumption. I believe this to better optimize weight vs using more layers over the entire splitter or bolting on aluminum L channel.

So I would like to apply this targeted reinforcement to the front plate. Any input is welcome!

[bigjae46]

This is awesome. I’ve seen some structural CF pieces use aluminum around any structural areas to reinforce it. But I think some oversized washers on the bolts would do the trick nicely as well.

Similar to this video around minute 5 mark: https://youtu.be/jsT561opKrU

Might be different since its a foam core piece.

Thanks. I'd probably use an infusible soric core away from the bolt holes if that's the route I go. I need a better understanding of how the plate will potentially flex. For example, I used unidirectional fabric in certain areas of my front splitter instead of just adding another layer of 2x2 or biax cloth. Unidirectional is the stiffest fabric in one direction, twill weaves split that stiffness in half in two directions. When I laid up this plate, I alternated between a 2x2 twill and a biaxial cloth.

I should be able to save up to a lb and achieve similar stiffness as 9 layers if I can lay up 5 layers of alternating 2x2 and biax and place 2-3 layers of unidirectional fabric in key areas.

[eacmen]

This is awesome. I’ve seen some structural CF pieces use aluminum around any structural areas to reinforce it. But I think some oversized washers on the bolts would do the trick nicely as well.

Similar to this video around minute 5 mark: https://youtu.be/jsT561opKrU

Might be different since its a foam core piece.


Sent from my iPhone using Tapatalk

[bigjae46]

Finally an update! I’ve put 12 days of track use on it, car pulls up to 1.61 lateral G’s according to my AiM Solo DL. The plate has survived. I won’t say that I noticed a huge difference but I did set PRs on 3 track configurations.

I was concerned that the front edge of the plate where the aluminum c-channel is bolted wouldn’t not be strong enough to take the loads of the splitter. Turned out fine.

Only change was I ended up bonding some fasteners to bolt the underbody panels too.



No concerns with damage around the bolts. Just the normal galling from torquing up the bolts.






There is one spot where the export yellowed. Right near where the exhaust manifolds pass by the plate.


Overall it’s a success!

I’d like to see if I can improve the stiffness and make it lighter. Might use 2-3 fewer layers of carbon and add targeted pieces or incorporate an infusible core

[Lee_Enfield]

Neat.

I've also been thinking of messing around with carbon fiber. But I was going to start with some easier stuff, like engine covers or other cosmetic bits like the "M3" plaque on the door sills.

I would not worry too much about the aluminum washers. If they are there to protect the carbon they are sacraficial and cheap. When it comes to corrosion, the aluminum washers will take the hit over the steel bolts or the frames when it comes to galvanic. If your concerned of environmental corrosion, you could just coat the fasteners with a corrosion preventative compound. Just a touch on the boltheads/washers.

[maupineda]

How is the carbon reinforcement plate going?

[bigjae46]

Next project: Carbon Fiber full flat floor with CFD modeled aero venting for trans and diff. 🤑🤑🤑

Well...that might be next. I need to get this plate right first. I have been planning on making a section of flat floor on the underside of the plate. Possibly filling the void with structural foam. Then two halves of the floor between the wheels.

Still brainstorming the diffuser.

TThat's a little ways off. The next carbon projects will be focused purely on weight loss - bumper, hood and roof - these should help me get to 2525lbs. Then I can re-do the roll cage in 1.50x.095 wall tubing which meets SCCA, NASA and BMWCCA. Final weight should be around 2475lbs. That should be one of the lightest E46 M3s...if not the lightest!

[bigjae46]

Nice.

CSL concept car had this:

Thanks! I saw that a couple of days ago.

I took it for a spin around the block. Felt about the same...a good thing. Inspected it and everything looks good. I hope to get it on track Apr 9 with Chin Track Days at MSR Houston to test it. The plan is to drive withe CF plate during the day, inspect after each session. For the happy hour, swap in the aluminum plate, drive a couple of laps and then swap in the CF plate and drive some laps. See if there is a huge difference. Not really expecting to be much of a difference. Mostly want to test how well the plate holds up. Specifically the front tabs where the front splitter connects to.

[Obioban]

I didn't used to follow the procedure and replace the bolts every time. Since FCP came into existence, I do.

[eacmen]

Awesome concept. Side comment, does not torquing the plate correctly contribute to any loss of rigidity? I usually just give the impact gun a few ugga dugga's

I’ll admit I don’t follow the torque procedure and don’t replace the bolts each time.

Haven’t had an issue yet.

[Kdubski]

Awesome concept. Side comment, does not torquing the plate correctly contribute to any loss of rigidity? I usually just give the impact gun a few ugga dugga's

[nahvkolaj]

Next project: Carbon Fiber full flat floor with CFD modeled aero venting for trans and diff. 🤑🤑🤑

Might be able to sell something to Mercedes AMG after that 😝