Yet another E30 project thread

[mecmw]

Well I've just embarked on yet another project...

The story goes...

I popped in to the last BMWNSW sprint at Eastern Creek to say hello to a couple of people. When I got there I noticed a very mangled car on a trailer in the car park. I didn't recognise the car at first, but eventually realised it was (used to be) a very nice E21 racecar that I had seen before at Wakefield. It was decimated! The story was that it had rolled many times after falling off the track at turn 1. Thankfully the driver (who's name I can't remember...) was OK baring some grazes on his arm, a bit of a sore head, and some general soreness from being shaken around so much.

After looking at the car it dawned on me that if it had have been me in my car, I would probably be dead! At that moment I decided to build a cage.

My current race car is a supercharged 323i that some of you have probably seen (http://forums.eurocca.net/showthread.php/23427-E30-m20). It is a 4 door shell that is in pretty good condition, however the little bit of rust in the firewall (from an exploded battery somewhere in it's history) has always concerned me a bit. To fix the firewall I would have to pull the engine out, and I figured that there was an easier way that would end up with a far better result... Buy a new shell...



I picked it up on Saturday. It is a base model Sept 1988 318i two door. I got it quite cheap on account of the fact that the engine wouldn't run. The shell is perfect.

My plan is to build a cage in this car, and once that is all done swap the engine/drivetrain/suspension across from my current car as complete assembilies (crossmembers and subframes). That way I will still have the car available (almost) the whole time.

So far all I have done is started to strip the interior. I'm up to the bastard job of pulling the heater/AC assembly out...



I also went to Jaycar and bought a little digital scale for $20 and I am being maticulous about weighing everything I pull out. My plan is to populate a nice spreadsheet with the weight of every component/assembly for the future.

Needless to say, I've got my hands on a whole heap of parts that I want to get rid of. Stay tuned in the classified section if you are after spare bits for your engine(M40)/drivetrain/interior/suspension/etc...

[Stoney]

finally, someone who is actually weighing all the parts when it comes to removing weight, did you do weigh the car, before you started stripping it?

[mecmw]

did you do weigh the car, before you started stripping it?

Unfortunately I have no way of doing this without a trip to the weighbridge. I'm only weighing "standard" stuff, so the tare mass on the compliance plate would be a good guide.

[mecmw]

OK, I'll be putting these in one big spreadsheet eventually, but I can't resist putting up a running total of weights...

So far from the interior;

Back seat - 7.39kg (top half), 5.97kg (bottom half)
Front seats - 17.48kg (drivers), 17.55kg (passenger)
Front seat belts - 1.30kg each side
Rear seat belts - 2.48kg total
Parcel shelf - 2.73kg
Glove box - 1.65kg
Front door cards - 3.02kg each
Rear "door cards" - 1.41kg each
Heater assembly - 8.00kg
Interior carpet - 8.30kg
Dashboard (bare) - 7.15kg
Battery - 14.64kg

Running total - 104.8kg

And there is still a big heap of interior "stuff" piled up inside the car yet to be weighed.

I can't believe that each of the front seats weighs more than the battery. Note that not all of this is weight reduction as obviously some bits will have to go back in...

[SimonM]

Nice work.

BTW, the E21 belongs to Craig N from Canberra, he did indeed roll multiple times at EC T1. He's pulled up fine, and is about to strip the good bits out of the car. Unsure future plans, he's been offered a good E30 shell. I agree with your assessment - if he didn't have a cage, he'd be a dead man. I'm glad I've got a cage, and it really makes me question how far people are willing to push things in supersprint formats. It might be fine if the car is fairly standard, but if you are running decent power, suspensions, tyres, big brakes, it really is time to start down the route that you have here, and get yourself some rollover protection...

[mecmw]

14.7kg of sunroof is now gone. I just need to tidy up now.

Sunroof cage.jpg
Sunroof gone.JPG

The weights were;
Sunroof hardware (guides, cables, winder tracks, fabric cover etc) - 5.2kg
Outer skin - 3.15kg
Inner skin - 2.01kg
Cage - 4.34kg

The only bit of this going back in is the 3kg worth of outer skin. I separated the two (inner and outer skin) fairly easily by breaking the spotwelds with an old chisel. The only issue is that the outer skin has a little bit of rust in one corner that I'll have to patch up...

Rust in sunroof skin.JPG

[cplagz]

If you dont want your carpet, let me know

[Stoney]

i had serious thoughts about stripping my spare e34 when i was living back at home and had heaps of spare time, just for the sake of it, i love removing stuff,

i had my rally/paddock hack R31 down to nothing, no doors, no panels, anything that wasn't needed to make the car run was removed, and with a manual and welded diff, it was fun and scary, weded in a few support and saftey bars in strategic places, and off we went in our mates 100 acre farm

point of that story, removing weight is your friend and much cheaper than adding horsepower

[e30guydownunder]

I also went to Jaycar and bought a little digital scale for $20 and I am being maticulous about weighing everything I pull out. My plan is to populate a nice spreadsheet with the weight of every component/assembly for the future.

We all start with good intentions

I pulled 11kg of insulation out of the cabin, there is somewhere around 8kg on the bottom of the chassis, not worth the effort IMHO

I'm surprised how much weight you have stripped out of the insides to be honest! My car might be lighter than I imagine.

Car looks strangely familiar Good to see it continuing on in life with a good purpose

[mecmw]

I've been quietly chipping away at the cage build lately. As of today, the rear 4 point is finished and I'm about to do the final measure up for the front hoops.

In the picture below, it's just sitting on the pads, but I am about to tack it in place while I build the front half of the cage. My plan is to do the usual cut-a-hole-in-the-floor-and-drop-the-cage trick for the final welding when I get to that stage, so I'm not welding this in just yet.



The 4-point was TIG welded together out of the car and I'm going to continue TIG welding wherever I can. My skills on the TIG are getting to a half decent standard these days; I just hope I can keep it up when I'm welding upside down with my head in the footwell later on. Here's a sample...



I also made a nice taco former and have the use of some dimple dies to make lots of pretty gussets. I did borrow a taco former of E30guydownunder, however, being the fussy bastard that I am, I decided that it wasn't close enough to size and made my own (ps:- when do you want your former back Chris?).

[mecmw]

By the way, I've been trying to work out if I need to close out (seal) the rear bulkhead and parcel shelf.

I see people do it all the time, but as far as I can tell, it is only necessary (mandated) if I have fuel in the boot. Any thoughts??

[matt_dumesny]

Welds are looking good, TIG is the only way to go for cages and exposed bar work. Though, like you said, unless you can do it left handed and upside down with the pedal taped to a bar somewhere way above your head, it doesn't count...
I learnt this the hard way.
"You can TIG alright cant you?"
"Yeah"
"Fix this up then"
A crack in the base of one of those mobile harness racing barriers, only this one had a rotator for handicap starts...

Good luck with the rest of it, no doubt it'll come up well.

[e30guydownunder]

Taco former you can hand me with the radiator before November. Welds looks heaps better than mine! I think technically you either need a Battery Box or to seal your firewall. I would argue it won't get picked up, but what are you going to do when you want a surge tank on this thing?

[mecmw]

what are you going to do when you want a surge tank on this thing?

Put it in my spare wheel well and then seal that...

[e30guydownunder]

and as thats where your battery is I would say don't worry about the parcel shelf SOLID PROGRESS by the way. Looks really good