Das Kart. A build diary of a cheap sportscar.

My children are approaching driving age, so I needed an appropriate project to begin for all of us to share. I have also be saying to my son for a few years that I would like to do a kart build.  So I mentioned the idea at dinner, and we decided on the criteria for our upcoming purchase. RWD, or AWD, manual transmission, under $1,000, and within 500 miles.  That is really all it takes to make me happy.  I had always pictured doing this build with a wrx, but I kind of expected to end up end some vq powered turd, as they make up a large portion of cars fitting my criteria. 

After dinner we started looking at cars to see what was out there, and within 10 minutes I bought this car.

So here is the nitty gritty. It spent it's life in Minnesota, and was totaled for body damage.  A tree fell on the car from the left front towards the b pillar. Damaging the fender, hood, a pillar, roof, and passenger mirror, and destroying the windshield. The car is a 2003 BMW 325 XI, 130k miles, 5 speed, and original tires.  The interior smelled like a bowling alley in the 90's, it wasn't cleaned often, but seemed to run ok, and the 100 feet I drove it didn't give me any cause for alarm. The car was purchased on 3/1/21 for $750

I found a glass guy said he would do the windshield for $250 cash, and I accepted.

The glass was installed without incident, and I was excited to start playing with the car.  I ran some baseline tests, but the car had enough deferred maintenance there was not much point.  The rear shocks were dead, and the fronts didn't feel much better.  There was an ignition issue, and it had the original radio.

The most important thing to me, was to get a weight before I took anything off. 1/2 tank of gas, the car appeared totally stock, and original. 

what a pig.  Ah well, balance is nice, and this just means more weight to take out.

Obviously the muffler had to go immediately.  We weighed all of the components that we removed at this stage, and took notes.  Not too many surprises, but the muffler was 36 lbs! At this stage, the car was in what I consider "trackday" trim. Everything heavy, or easy to get to is pulled.

I also did plugs, and coils, CEL went away, and the car is running great. At this point I was just using this car as a daily.  Trying to find out all the things that need attention, or weird things going on with the car before the weather starts to get nice, and I want to really start getting after it.

Above is the first pile of parts we removed.

I bought these wheels and tires from a local pick n pull for $150.  I believe they are from a 5 series, as the diameter is larger, and made the already too high ride even higher.  I also picked up a pair of rear shocks for $15.  I removed the hood, trunk, and both bumpers. 

Then I broke the rear glass.   I should have known better, as it didn't take much.  Truth is, i wasn't going to try and sell it, so it may have just been easier to get rid of this way.

I have drawn some lines where I intend to cut.  Most of the areas just follow body lines, and I can always cut more off later as I add structure back in.

Ok, this seems like a reasonable time to start cutting this perfectly good car in half.  I used a sawzall for pretty much everything.  I used an angle grinder for some small stuff.

Back of the car gone.

While working on the car, my magazine showed up, along with my EA plates for my other car.  In my state these plates are much cheaper, and you are only supposed to drive from April-oct. 

I welded this "bumper" on a while ago to try and be somewhat legal, the lights and CAI I had laying around.

I taped the lights on and drove it around, and man was it terrible. Obviously I did not want to be short with my main hoop.  It will not be as tall as it looks in the picture, but I do not see much benefit in this particular car to keep the cage tight to the occupants. 

The rear tubes will land here.  I plan to tie them in with the shock tower.

My next post, I will weigh the car again, and detail the roll bar install.

That went from 0-100 really quick. Never seen a manual, e46, awd sedan IRL let alone a BMW kart.

Haha! I love when I get to break the glass too. 

Well that escalated quickly. 

Yes, kart it all!

Yeah, sorry. I have bee glossing over a lot.  Allow me to summarize. At this point, the car has only had parts taken off. With the following exceptions.

Windshield $240

New plugs, $27.21

Used rear shocks $9.98

Used wheels/tires $150

CAI $0

$427.19

I also put in a Pioneer stereo, and phone/tablet mount.

I had the stuff on hand to piece together a cai, so I could delete the stock airbox.  I also removed the air conditioning, the smog pump, and I accidentally wrecked the evap canister, and one hose during the ass removal proccess.  I will need to address this, but I am not sure how I will proceed yet.

looks like fun!  i still have my E46 ZHP and enjoy driving it... not as much as my vette-kart. surprised you are keeping the dash or anything interior related. 

i agree with your rear cut line, leaving the rear fenders... its amazing how much junk open wheels fling forward.

OOF! This is not the number I was hoping for. There is some evidence that this scale is high, but it should be relative to itself. 

The way these doors connect to the car is a thing of beauty.  Three fasteners, and a wiring harness to unplug, and the door is off the car.

This is about where the cage will land.

Here are some pics of the templates I made using a profile gauge.

I wanted the main hoop to be at the same height as the stock roof, and I am happy with the results.

Another pic of the box.

Moving towards the rear of the car, and the process continues.

Starting to look like a sportscar.

Good fit is important.

A little while later, and the back is good to go.

I have been leaving a lot of "car" just so I don't completely screw myself.  It's time however, to start trimming up some of the areas I left a little proud.

So much for what was left of the fenders.  I will probably cover them back up, but it's not too much of an issue with these poopy tires.

I want to keep all the stock emissions stuff, but it's big. 

I drove it around like this a little, and it was hilarious. 

Thisis great. I hope you posted on a BMW forum somewhere. 

Wow, a year already... I am now going to get this thread up to date, as I am better at working on cars than I am about making build threads.  The stock seats need to go, and I am taking the easy way out with these seat brackets.

I then chopped the remaining roof, and b pillars, and installed the seat.

The dash is removed to facilitate the front section of cage, and to remove the heater core, and associated bits.

The blower motor housing is also the firewall, which creates a large hole upon its removal. This is taken from the front of the car, looking at the back of the blower motor housing.

Now it's out.

Here is the template for the front of the cage.

Bending, and test fitting the drivers side front bar.

The drivers side in place.

and passenger side.

I cut a section of the dash structure out to mount the steering wheel back on. My plan is the connect the cage to this part of the oem steering mount.

At this point, any reasonable person has already realized that this car is now driveable again.  So I went and drove the car around, and there are a few issues that need to be addressed.  The windshield moves around, and not a little bit. I cut out some gussets, and made it strong.

The rear shock towers are pretty ugly, and I plan to chop them off.  The stock springs are way too tall now, and the car sits with the suspension near the end of its travel range as a result. I made some spring adapters for some universal springs.  I did some math based off the earlier corner weight data, and some interneting.  I am starting with 200lb springs. This is the upper spring mount area.

I got some other bars put on the car, and picked at a couple things. At this point I pivoted to another project, as I needed to get a car ready for a lemons race. This is how the car looked in late summer/early fall as I worked on other things.  After a string of failures in other automotive pursuits I put this car into the trailer in october, with plans to leave it there until at least the first of the year. Here is what it looked like when I put it up for winter.

I have to admit that when I first read this thread last year, up to the point with the big cliffhanger, I had... doubts. Hence not commenting.

Now it seems I need to go buy a hat so I can eat it. Because this thing is amazing. 

I can understand why one would think that.  At this time it appears that this story has a happy ending.

What's the weight sitting at now?! 

I haven't weighed it again, but I will try to find out soon.  Maybe 2700?

My son and I play racing games, and we started building a sim rig.  Got the seat problem taken care of.

In January I bought a car that needed to live in my trailer, so I pulled the BMW back into the shop, and started picking at little stuff. I bought a heater core delete kit, as well as a firewall block off plate from bimmerworld.  The intake manifold has to come off, and the block off was installed.

My kids started bugging me about painting the car, since it was just sitting there.  So we decided to paint the front, since we planned to rattle can it anyway.  After much deliberation we "agreed" on the closest we could get to laguna seca blue. 

There. Now the kids will be placated for a little while.  I removed the front strut assemblies and suspension arms, and I will be replacing all the bushings.  I bought oem replacement front struts, and hr springs.  This is really the only combo I can buy off the shelf that I think will work for me.  If this setup doesn't work well enough I will have to make something. For whatever reason, I didn't really take pics of the bushings, and front suspension stuff.

I then moved on to the firewall block off plate. The piece was nice, and came with rivets.

Here is a view showing the oem rear damper mount, and the drivers side removed.  The plan is to keep the new mounting location in line with the old, and to just shorten the overall travel length.

Here is the new mount in place.

Here is both sides completed.

I used summit racing to search for shocks that would physically fit, and matched to a similar spring rate as it would have been used.  These are rear shocks used in a ton of gm cars.  I am starting with 200lb springs in the rear.

The door bars had already been bent, but I was waiting as long as possible to install them just to make it easier to get in and out. 

I am going to remove some wiring, and clean up some things.  Soon it will be development time.

I planned to get it on track as soon as possible to start shaking it down. My initial impressions from driving it on the street was that the rear was too soft, and it needed to be addressed before getting on track.  The unfortunate thing about the e46 xi cars is the lack of aftermarket support. Most of the stuff says "*excluding xi" I  read a comment written by a stranger on the internet who said the hotchkis rear adjustable would work, contrary to what they claim.  So I bought one, and put it in.  Unfortunately my phone camera broke, and I didn't get any pics of the swaybar install.  The install was straight forward, although I had to do a little convincing with a sawzall getting the oe stuff off. Thank you internet stranger, you have helped me.  

I started with the swaybar setting on the softer of the two positions.  I know I will not be happy with the swaybar there, but would like a baseline.  It is such a huge improvement over the stock bar.  At this point, the only "performance" parts on this car are H&R Sport springs, and the 2 position 24mm rear bar with endlinks. I aligned the front of the car to straight, and 0deg toe. I am not messing with camber yet, as the tires I have are trash, and it can wait.  I set ride height in the rear to level with the front since the front end is all fixed setup.  Next up we hit the track.

The track we will be attending is Autobahn Country Club in Joliet IL.  https://en.wikipedia.org/wiki/Autobahn_Country_Club It is a safe track, and I have a lot of laps here.  I had recently just set some hotlaps in a bone stock 330i automatic on all seasons, so that is my baseline.  Autobahn south track in the stock, auto 330i 1:53.2.  My first session out my best lap was a 1:45.7 which I was pretty happy with considering I was on very old 225/50/16 Azenis. That is what the faster lemons cars run around autobahn south, and this car is pretty much just a lemons car without the outside if we are being honest. My son pointed out that we should get a good camera, and I think he is right.  Here's ol' racebrick coming in from a successful test session.

I immediately knew coming off track that I wanted to bump the swaybar to stiff. The car really understeers under power, and is just generally to pushy for me.  The rear of the car is undersprung, but the brakes felt good, and overall the car was well mannered and fun to drive.  I should also add, that at this point all assists are off.  I got the swaybar adjustment made, and went back out for the next session with my hotlaps being 1:44.5.  The car felt much better, but still way to pushy.  Power steering fluid was hitting the windshield, and I think this system just may not want to have the holy hell reved out of it.  I will need to investigate further.  My third session I dialed it back a tad, and tried to pay attention to any wierdness exhibited.  

Before next track day I will get stiffer springs, and install my big wang.  I also need to build some rear fenders.

Huh, thought I recognized that car.

Saw you at the cars and coffee on Sunday. I've got the 302 swapped XR4Ti. 

In reply to GPz11 (Forum Supporter) :

I will have to introduce myself properly next time.  We spoke a few weeks ago when I was there. 

Ok the moment you have all been waiting for.  We got it on the scales tonight, and I was pleasantly surprised.

Cool build.

Is it still AWD? May be a factor in excess understeer. Plus, it's pretty dang front heavy now compared to stock! Maybe you need staggered tires - you know, wider ones up front!

It is still AWD.  According to what I have read, this car is split 38% front 62% rear for power distribution.  I have considered doing a staggered setup, but will probably just put stiffer springs in back, and try to find some more weight to take off the nose.