BMW Compact Rally Car Build

[DaveKern]

Managed to sneak in a little bit of work on the BMW over the weekend. Rally rules call for adding additional protection for the gas tank. There are many ways to skin this cat, but my preference is a few layers of kevlar. Unlike HPDE sheets, the kevlar can't get ripped off on stage, its bonded right to the tank.

Here's a shot of the gas tank after the first layer of kevlar had been applied.



I ended up with 3 layers on most of the tank, and 4 layers in some of the areas that I figured were more likely to be banged up with rock spray.

Dave

[DaveKern]

Picked up the car on Wednesday from SCR Performance/Built-by-Bones. The roll cage is done! Colorado weather in the spring/early summer is typically nice in the mornings, and spotty T-storms in the afternoon. I had to move the car in the afternoon, so I was really hoping I'd be able to avoid rain since the car hasn't been painted yet. I got really lucky, and managed to get the car moved to its new temporary home without it getting wet...missed the rain by ~10 minutes.

First up is a shot looking towards the roof structure.



Next is a shot of the windshield area. Note the super nice gusset plating with punched & flared holes, which add lightness and strength!



Here's a shot thru the windshield looking rearwards.



This one is a shot of the passenger side door opening:



Getting to the back of the car, here's a pic taken looking forward from the rear hatch area.



Finally is a shot of the floor so you can see how we've tied the seat rails into the roll cage structure. Some floor pan notching allowed us to mount the bars even lower than you'd think.



Next up will be to add lightness, i.e. cut out stuff that's not needed. If anyone has thoughts on what can be cut out that I haven't taken care of yet, I'm all ears.

Also, with the Euro debt crisis, exchange rates are getting pretty favorable. I may be placing an order for a compact body kit somewhat soon. Should anyone be interested in combining an order to save on international shipping, please let me know. Parts I'm getting will be coming from www.hh-ms.com

Thanks!

Dave

[ChItalian1027]

Looks good Dave!!

[tiFreak]

sick, that's one hell of a roll cage

[Jean H.318TI]

thats the cage i want

[cooljess76]

Holy Hell! Looks like a giant robotic black widow built a nest in your car!

[mohaughn]

You should take a look at some of the mod level cars built for BMW CCA. A lot of those guys do full cages like what you have with all of the gussetting and support at the A and B pillars. In a lot of cases, they gut all of the interior metal. Like the metal pieces that are immediately to the sides of the rear passenger seats. Most of that metal is not structural at all, and pointless once you tie a cage into the unibody like you have.

There are actually some pretty good photos where one of the guys went at his car with a hole saw.. I'll see if I can find the thread in the build forum for you.

[scandflik]

I am building a 95 M3 rally car. I was wondering what suspension you are using and how much travel you are hoping to get. Also what wheels do you have? I am shopping for wheels right now.

[DaveKern]

Originally Posted by scandflik

I am building a 95 M3 rally car. I was wondering what suspension you are using and how much travel you are hoping to get. Also what wheels do you have? I am shopping for wheels right now.

I am working with JVL on suspension for the car. He uses beefy non adjustable bilstein dampers. Since the hatch and coupe/sedan don't share the same rear suspension, the rear stuff we are working on won't fit, but I'm sure he could put something together for you. Pricing on my setup is going to be right around $1900.

For wheels I will be running Compomotive TH wheels, which I scored from a guy who used to rally a compact ~10 years ago. There are pics earlier in this thread.

Dave

[PrimeTimeSlime]

Hey Dave, Any updates on the car?

[DaveKern]

Originally Posted by PrimeTimeSlime

Hey Dave, Any updates on the car?

No real progress to report. I am in So Cal at Mitsubishi HQ at the moment. I dropped my Evo off with ACP (nos energy drink rally driver) so he can have a backup car for the races.

What does that have to do with the BMW you ask? I now have an empty garage, so the compact is going to get some love over the next two weeks.

My goal is to have the bottom of the car prepped so I can start bolting some parts onto the chassis. My garage is so full with bmw parts scattered across the floor, but I suspect that the loaded up chassis won't take much more room, so hopefully I can get it to fit in there with the evo.

Dave

[DaveKern]

Spent the 2nd weekend in a row in the garage cleaning off the bottom of the car. The liquid nitrogen worked well, but there's still so much gunk all over the place. Very frustrated. Really wishing I had just sent the car out to get acid dipped right about now. The OCD in me wants the underside down to nothing but roughed up paint so the macropoxy will stick well.

Now a question for you guys - I'm looking at picking up a clutch for the car and would like to do a lighter weight flywheel as well...but I can't afford to break the bank on them. I just figure while the engine and trans are out of the car, now's the time to upgrade. My plan for this first season is to keep the M3 engine as is (intake, exhaust, chip), so I won't need super amounts of power holding...but I also want to be able to clutch kick the car and not worry about the clutch giving up.

Thanks,

Dave

[J!m]

UUC is a great source for clutch/flywheel packages.

Check them out (or better yet- give a call!)

Nice build by the way! I have a friend who wants to do something similar...

[DaveKern]

Made some progress tonight. Finished prepping the transmission tunnel and parts of the rear portion of the car. Mixed up 24oz of the macropoxy and went to work. Its a two part paint that lots of guys are using on budget builds instead of expensive undercoatings or plastic sheeting. Supposed to do a pretty good job of protecting the metal from rock blast. I'm trying to split the difference on my build, so will be using a mix of kevlar and macropoxy to keep the chassis in good shape.



The stuff goes on pretty thick so you could see brush marks, but as it sat there, it started to smooth out a bit. I may see if I can thin out the mixture a bit for the next time I do it...but so far so good.

Dave

[wolferj-RIP]

Originally Posted by DaveKern

Spent the 2nd weekend in a row in the garage cleaning off the bottom of the car. The liquid nitrogen worked well, but there's still so much gunk all over the place. Very frustrated. Really wishing I had just sent the car out to get acid dipped right about now. The OCD in me wants the underside down to nothing but roughed up paint so the macropoxy will stick well.

Now a question for you guys - I'm looking at picking up a clutch for the car and would like to do a lighter weight flywheel as well...but I can't afford to break the bank on them. I just figure while the engine and trans are out of the car, now's the time to upgrade. My plan for this first season is to keep the M3 engine as is (intake, exhaust, chip), so I won't need super amounts of power holding...but I also want to be able to clutch kick the car and not worry about the clutch giving up.

Thanks,

Dave

+1 for UUC/Fidanza LTW flywheels...