A vintage BMW race car build....Racing all over California with VARA in C-Sedan!

[iwantspeed]

great work

[bmw1602.com]

I decided if I was going to ever finish this I would have to start working on it during the week, so I started to go to the shop after work these last 2 days.

Good thing too as we are making great progress....

welded in the subframe posts,


Welded the tube section to side of the "box" as well for additional support.



also did some additional "seam welding" where ever the mig gun would let me.




last step before I weld the cover/base plate is to drench/cover the entire area with POR-15

[bmw1602.com]

Next we started working on the main "X" on the down bars. In case you were wondering DOM tubing is 1.5"x0.095 thick. This is in line with the rule book for a 2000lbs car.



I'm using his welder and Im still trying to figure it out but Im getting decent results.....







Me sparking it up!





It's getting tighter and tighter back there everyday .... more tubes to come !







here is the completed section........ next the "X" to connect the subframe to the cage.

[Rickysbmw320i]

All i have to say nice damn job! amazing!

[bmw1602.com]

thanks!!

Welded the plates in and completed the subframe connector tubes....incredibly I have never seen another '02 with this done to it. I've seen people weld tubes to the area but never actually do it like all the e30 and e36 guys do.






My "comrade" Dimitri, none of this would of been possible without his chain smokin' helping hand.



We are using a Harbor Freight tube notcher in case you where wondering.

Next we tacking in the subframe downbar.

[bmw1602.com]

I have to smile when I remember the funky ass positions you have to get in when welding a cage!

here I am welding the first tube connecting the subframe tubes to the rear tube node.







I can't stress this enough.... when welding ANYTHING get as comfortable as you can get. The more comfortable, the better you can see the cleaner the material is the better your welds will be.....mine are not perfect but it's amazing how much better they are when I happen to be in a more comfy position. Supporting your mig gun with your other hand can be tricky at times when welding in weird positions, but is vital to use you second hand to stabilize the nozzle to give you most control over what you are doing as possible.....

Much like Jaffster I initially planed on Tig'ing the cage but in the interest of saving time I opted for the MIG. After welding some of these tubes I have a hard time imagining doing some of these beads in weird positions with a TIG.... having to manage the filler rod and the pedal would of really been a challenge! not to mention just fitting the tig torch in some of these tight confines.....

in any case he is me after I found a "comfortable position allowing me the best view of what I was welding.



the result I must say almost brings a tear to my eye....hehe

Personally I never seen this design done on any 2002 or e30. I think it's elegant and make perfect sense "engineering wise" and much better than other "subframe connector tube" designs. I just looked at it and this is the design that made the most sense.









All the "black" tubes are the new tubes in case you did figure that out already.



here is a closer shot of the finished subframe tube





like I said not perfect.....but not bad either....

[bmw1602.com]

Decided to add a horizontal tube across the main hoop legs and stitch it to the transmission tunnel. This tube should help considerable if the car gets t-boned right around the main hoop/door area. It should help keep the cage from collapsing inward. Basiaclly should help support the mid-section of the cage in a side impact.

It's safe to say after my new (coming soon) door bars and all the new tubes the car should be much safer.

It was trickier to fit than I thought as we had to cut a diagonal notch for the diagonal bar from the main hoop.....

this one was not so great...





The driver side weld came out nice.



Then I welded the tube to the transmission tunnel, should help integrate the cage in one more location to the unibody (there are many others)





and now the complete view of this weekends work...including the new tranny tube....

[B.Watts]

IAfter welding some of these tubes I have a hard time imagining doing some of these beads in weird positions with a TIG.... having to manage the filler rod and the pedal would of really been a challenge! not to mention just fitting the tig torch in some of these tight confines.....

Some of the pros I've seen doing cages have taught themselves to use a finger control on the torch instead of a pedal control. And then they use MIG for those tight positions where they can't get the TIG.

[Steve J.]

You can get some interesting techniques when using the food pedal...it becomes an elbow pedal, knee pedal...you know a body extremity, and it can operate the pedal if needbe

Mig is great at filling gaps while keeping structural. Tig is great for all those very tight fitting tubes where there is zero gap (less gap the better obviously).

Your welds look ok, but it might need some more voltage, they don't look like they are fully penetrating in those last couple pictures. You should do a test peice with the same technique/settings, and cut it to see the weld penetration. its probably pretty good, but its worth it to check the settings to make sure you are getting a strong weld.

[bmw1602.com]

Yes I have tried the foot pedal in-between my knees and using my elbow before too....In the end the mig just gets the job done so much faster! definately not as pretty as my tig welds..... I might Tig the door bars and related dimpled gussets around the cage....

I'm using a 220v hobart mig welder, I have it turned up really high actually, I did do some tests on a slice of tubing and a plate and the penetration looks good. I can actually see the puddle melting both tubes while welding. It's looks very different than the weld pool when I'm use my 120v miller. During my initial tests with my 120v 20amp Miller to see if I could get away using it since I was using .95 wall tubing. I could tell right away I just didn't have enough heat in both metals to get full penetration. Which is why I towed my car to my friends shop to use his 220v Hobart.

I wanted the extra current/power to ensure there was enough power to properly melt both tubes together even where I might use .120wall tubing. After doing all this welding this last week and looking at these pools real closely. I'm pretty sure that I'm getting proper fusion.

Hopefully I never have an opportunity to find out....

[turb02]

Pedro, do you have any races in the midwest anytime soon!? I would love for a cage like this in my project!!!

[bmw1602.com]

Pedro, do you have any races in the midwest anytime soon!? I would love for a cage like this in my project!!!

at this point if I make it to ANY track by next year I'll be happy...I still have so much to do! brakes.......motor rebuild...new wiring....

I encourage everyone reading this to start learning the skills necessary and try to do things yourself! It might take some practice but it's incredibly rewarding.

I never rebuilt a car engine before.....I'm looking forward to it!

[bmw1602.com]

What do you think my car is powered by?



A hungry poor brazilian !!




This is what happens when you drink beer and work on your car




But seriously, I was in there to check the hood clearance on our new new "strut tower" design. If you look back at my ver.1 and ver2. ......something just didn't work for me. Thanks to Dimitri I think we finalized on a "strut tower" tube design. I feel much better now !

First step was to check the hood clearance........I shave my hood reinforcement support bar that I fiber glassed in just enough to make room for the tube.



Next I broke out the cardboard and started laying out the strut plate and tranfered it to steel, using 1/8" plate. It was a total bitch to cut it out while maintaining straight lines etc.... even more challenging to cut out the center opening.





Next the moment we've all been waiting for......drum roll please

First hole in the firewall.....!!!!!!!!!!!!!!!!









Getting the hole cut and lined up in just the right spot? ....priceless!



TUBING is 1-1/4 x .120 wall

It's all downhill from here!

let's see how our idea all comes together

[bmw1602.com]

quick update.....

welded in the dash bar, in preparation for the strut tubes...so they have a place to join to..

[PEI330Ci]

Great thread! It's really refreshing to see a non-e36 build being done so well.

Thanks for sharing

[bmw1602.com]

Thanks! It's keep me motivated!

Now I just need to get a nice DSLR and work on the shop lighting to get the same amazing pics you get!

Just wait to see what I'm doing with the shock tower tubes....I think the design we came up with was better than my versions 1 & 2 that I posted earlier in the thread...

Unfortunately I will not be able to work on the car at all next week.....

[bmw1602.com]

Front Completed!

Well after much thought about my previous ideas for the front shock tower tie-in....We came up with another Idea. Problem was when we start actually looking at all the different sheet metal structures that make up the "shock tower" on the 2002. After many ideas we decided that with this design we leave the stock structure of the strut tower unchanged. Basically I will use the new tubes and gussets to integrate them into the stock structure and the resulting design should increase the overall stiffness and strength of the front of the car.

Basic idea was to lay a thick 1/8" plate over the top of the mounting area. The run horizontal tubes from the dash bar (like many e36 and e46 designs) and then run one tube from my existing lower "dash bar" to give it some horizontal support.





vertical support tube mount to the lower dash bar...



here is a good side view of the completed design.





the gap on this tube is not as bad as it looks it just the way the tube is laying there as none of this is tak welded in yet....


Completed layout (not welded yet...duh)





Maybe not as pretty or elegant as I might of imagined but we managed to come up with a unique effective design.

This is what it looks like in one big pile...... ready to get prepped for welding....

[bmw1602.com]

Granted I'm vintage racing and the racing is not at the same agressive level of what I encountered on the "Setup" tv show or even your local NASA or scca race. But the single door bar always made me uneasy and was never a permanent solution.

I decided to maintain the main tube already welded in and transform the existing tube into a door X design. This should once again help with chassis stiffness and more importantly safety.

I will be adding dimpled "taco" gussets to the X as well as many other parts of the cage.



Dimitri played a joke on me!.......who knows the tubing might actually be from china.



Now for the driver side I decided to run and additional tube connecting the center of the x to the door sill tube. This should help in a side impact. Also as I said I will be adding many gussets...



So now I'll feel a bit more safe in that seat.....

[bmw1602.com]

After seeing some this on some other build threads I'm really surprised I didn't think of this before!

Basically just a tube that's connected to the cage so you can jack the car up from one centralized point and get both wheels in the air at the same time. Which is great for enduro pit stops ala Nascar style or just convenient so I can place both jack stands at the same time.

I would of liked to have placed it a bit closer to the middle of the rocker but there was some things in the way (maybe side exit exhaust). The bigger issue was also the sill tube bends out and the jack tube would not of lined up. In the end my location works perfect.

Would of been sweet to have air jacks but.......yeah right!

Was simple cut the hole with the hole saw - then slide the tube to mar the trim point - then cut a notch.......done.



after the notch was cut.......



testing with the jack........



I might weld a plate to the end of the tube...






Nothing like some cold beer to celebrate the end of cage fabrication !!!!



Bottoms up! ......yeah it was freakin' hot in the valley.....it's always hot there.....

[PEI330Ci]

Great work so far! I really like the DIY aspect of this build.

Strut towers look good, it's a difficult chassis to build for in that area. Is it possible to have the inside top tubes attached towards the center of the dash bar? It would help triangulate things better, but I'm unsure on fitment with other components. I know working through firewalls is a tricky thing...there is a ton of time put into the routing/fabrication on my car. Keeping the stock windshield wipers in place made it even more difficult.

Thank you for posting clear well lit pictures making it easier to see what the heck you are talking about.

[bmw1602.com]

Great work so far! I really like the DIY aspect of this build.

Strut towers look good, it's a difficult chassis to build for in that area. Is it possible to have the inside top tubes attached towards the center of the dash bar? It would help triangulate things better, but I'm unsure on fitment with other components. I know working through firewalls is a tricky thing...there is a ton of time put into the routing/fabrication on my car. Keeping the stock windshield wipers in place made it even more difficult.

Thank you for posting clear well lit pictures making it easier to see what the heck you are talking about.

Thanks! We are doing our best with the limited tools and skills we have. We ran into sooo many situations where we wished we had the right tools!

I would of LOVED to go at a more diagonal angle with the inside tubes but I would of run into serious clearance issues with the carburetor and the distributor...... I still might run some short gussets tubes...

Also...another very important reason.

This design leaves the engine bay open to future configurations... after some vintage racing I will upgrade the engine package (which will make me illegal for vintage) and do some time attack and NASA GTS racing..... crazy I know.

My possible future engine packages
1-Turbo m10 (megasquirt)
2-M42 N/A around 180-200hp
3-Turbo M42 200-300hp
....
4-S14 - but this one is low on the list despite the easy swap because of the high cost for this engine.

At that future point the brakes will be upgraded, bigger flares, 15x10 wheels with 275/15 tires.....will be pretty good........pretty good. maybe in a year or 2.....

something like this........





Group 2 Flares (period correct)




Someday..........

[bmw1602.com]

So it only took all weekend to weld all the tubes in! Granted I only managed to get started after lunch everyday but it was alot of work!

I'm very happy with the finished product! Even tough in my crazed mind I kinda have an itch to add a few more tubes.......hehe.....

somebody stop me!

....next step is adding all the dimpled gussets......

here is this weekends work.....

First the plate.....



then the bottom support tube.......before



after


here it is from the other side...


then the top tubes





then stitched it to the fender



here you can see the 3 tubes that make up the strut tower tubes and the dash bar diagonal connector tube ( at least thats what Im calling it.)



left fender



closeup of weld....240V MIG welder FYI.....





A-Pillar strut tube joint.....



here you can see the diagonal dash bar connector tubes......I will gusset the lower dash bar to the transmission tunnel to ties it in further.

[bmw1602.com]

top view of a strut



top view......and yes that's my 200lbs ass standing on the dash bar....it's stiff!



Driver door bar ..... soon with gussets.



passenger door bar



front view




I THINK I'm ready for those 500lbs springs now!

[PEI330Ci]

Beautiful welds.

I think you'll be surprised just how smooth stiffer springs are with a solid chassis under you.

[5mall5nail5]

Wait a sec -



Judging by the pin hole in the center of each puddle, are you holding the trigger, then letting go, then starting again? The foot of the weld puddle in each of those spots is terribly cold and I worry your penetration is non-existent!