My 'lil deuce coupe: Build thread of my 1975 BMW 2002

Hi Everyone!

I've lurked here for years but never posted a build thread so here goes.

A little bit about me: GRM and the Challenge were my first introductions to motorsport back when I was in college with Wreck Racing. After graduation I worked in the automotive aftermarket industry and was involved with a Subaru time attack team doing engineering development before I moved to the UK to work in motorsport.





When I was in high school I bought a 1975 2002 from my late Uncle's automotive shop. My uncle was a big influence of my automotive interests, and probably the reason I was crazy about 2002s at a young age. Unfortunately after high school the car sat without much work done to it as I built up my motorsport career. I'm hoping to get the car running within the next 3 years for the car's 50th birthday. The goal is to do a modern interpretation of a 70s GT racer. In the short term I plan to swap in a k24 with Jenvey ITBs (the version that look like Webber sidedrafts). In the long term I plan to do look at doing an Alpina style widebody and hopefully with some aero/aerothermal design to enhance the performance of the car while trying to look mostly period correct.

Here's a picture of my late Uncle's 1969 2002 and my gateway into the 2002 world:

 

Here's a picture of the car from when I was 16:


 
This car has sat in various parking lots and storage for years. Finally today I had it towed to my friend's shop where I'll be removing the old M10 and trans and starting to plan out the eventual K-Swap with a Getrag 260 out of a 325i.



I live in England and the car is in America so updates will be sparse, but I hope to share my journey with you all, thanks for reading!

 

Cool.  I have a 76 2002 parts car that was free to me so let me know if you want free to you parts.

Following

Stampie said:

Cool.  I have a 76 2002 parts car that was free to me so let me know if you want free to you parts.

Wow thanks for the offer and your generosity, I'll let you know.

Following this for sure - my first new car was a 1970 '02 (color: Colorado) so I have a soft spot for these cars.  Your uncle's '69 is great!

You had a cool uncle.   

Thanks for the comments, I shared them with his kids and they really appreciated that!

Been a busy weekend, finished pulling the old engine and trans this weekend and this week I'll be looking at how the transmission fits in the car and hopefully doing some prelim CAD work.



Saw my old parking permit, probably the last time this car drove on its own!

New old mustangs, camaros, challengers...why can't BMW make a retro 2002....

Very cool project. 2002s are awesome!

Agent98 said:

New old mustangs, camaros, challengers...why can't BMW make a retro 2002....

Agree! I guess the newer M2 is the closest we will get.

Yeah, awesome!

My mgb gt shares a similar plot arc - bought when 16, drove a couple years, took it off the road for "projects" and now is in the middle of an engine swap. Albiet it's slow moving project. 

I'll read along and try to draw inspiration from you. 

Link to build thread, wow I even started the build thread a long time ago...

https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/rcutclifs-1974-mgb-gt/99434/page1/

Wow, been a long time! I remember you showing me pictures of this car back in the day. Excited to see what you do with it, especially given your career experience. Let me know if you're ever in Atlanta.

maschinenbau said:

Wow, been a long time! I remember you showing me pictures of this car back in the day. Excited to see what you do with it, especially given your career experience. Let me know if you're ever in Atlanta.

Will do! I need to make a trip out there, its been too long.

Robbie (Forum Supporter) said:

Yeah, awesome!

My mgb gt shares a similar plot arc - bought when 16, drove a couple years, took it off the road for "projects" and now is in the middle of an engine swap. Albiet it's slow moving project. 

I'll read along and try to draw inspiration from you. 

Link to build thread, wow I even started the build thread a long time ago...

https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/rcutclifs-1974-mgb-gt/99434/page1/

Thanks for sharing, I'll take a look!

k swapped 2002 should be really fun!

This is going to be fun to watch! Are you pondering a K20 head swap if you want this to rev? I'm guessing your base engine goal is to start with a K24A2 and not a Z3?

In reply to RKTFiST :

Yup start off as you have said. Not sure of anything beyond that at the moment.

I also hae a '75 2002 , a very long term project and will be watching your progress.  Have you pulled the carpet yet?  The foam used as insulation attracted and retained moisture.

The results, are predictable.

The last week with the car was hectic but now I have some time to make another post. After pulling the engine and trans out of the car I decided to put in the Getrag G260 into the car to see how bad clearances would be. It is pretty well known from those that do M20 swaps into these cars that the G260 does not fit easily in the 2002 and modifications to the trans tunnel would  be needed. roughly putting the trans into the car confirmed that:



The location near the pedal box is the worst offender, although since I have a 'I' transmission I have been told that these unused casted holes can be cut out:



Part of the issue is that I also have to account for the trans adapter, which is wider than the trans and 1/2" thick. Since I spend most of the year away from the car I decided to take a lot of pictures and start making CAD models of the car and transmission so that I can plan my next steps with the car.

Part of the goal with this project is also to explore low-buck techniques for engineering analysis and design. Here is a low buck method that I used to reverse engineer the K24 adapter I bought using cardboard, glue, grid paper, and a home printer/scanner. The CAD work was done in FreeCAD 0.20 which is truly free and open source. I am still learning it and comparing my experience to SolidWorks and the more powerful software  I use at work, so far however it has gone mostly well.

You can reverse engineer 2D parts with decent accuracy with this method.

1. First cut a piece of cardboard out that is larger that your part. Glue graph paper onto it. If multiple sheets are used take care to make sure grids are aligned.

2. Carefully trace out the profile of the part you want to scan. Likely the cardboard template will need to be cut into smaller pieces to fit in a home scanner.

3. Scan the template to your computer and upload into CAD (tons of youtube tutorials on how to do this for many CAD programs).



4. Check that your scan is at the correct size. Since you know the size of the grid paper you can measure the grid spacing to see if the scanned image needs scaling. Here the grid paper spacing is 6.35 mm which is close to the rough measurement I took here at 6.38mm.



5. Trace the image using CAD sketch tools. Good practice is also to constrain the sketch you make.



6. Extrude the sketch and you will have a reverse engineered 2D Part!

I am currently now working on the next step which are 3D parts. I am starting the transmission, and gathering from what I learn from that I will then do the 2002 Engine Bay and Trans tunnel.

The transmission is done in a similar manner to the 2D part, where I have scanned the front and rear trans profiles. I have also taken a bunch of pictures of the transmission and hope to use then to get an approximate idea of profile/size. The following pictures kind of show where I am at at the moment:







If this method works out, then recreating the 2002 engine bay would be the next step up in difficulty. One of the other reasons why I am exploring this method is so I can take pictures of modified 2002 trans tunnels from M20 swaps, scale them, and add them into my cad model to get an idea of what I would need to cut away. This is certainly not a perfect method but hopefully it gives someone some ideas on what can be done when you don't have access to a laser scanner.

Fast foward at year and I'm back in the US for vacation. My goal this year was to get the K24, and fabricate mounts on the car. Unfortunately everything didn't go to plan but I still made some good progress.

I first worked on removing the excess casting off of the G260 trans:

Before


After



I then went on with stripping in interior down and starting the trans tunnel modification. After removing the carpet I found
a couple trouble areas of rust that I will have to deal with. Eventually I will remove the floorpans off and put new ones in but
for now I will wirewheel and por 15 the current ones.




I then started cutting the trans tunnel. I started with the idea of doing minimal cuts, banging out the tunnel, and then adding
sheet metal as necessary:



However I later decided to cut the entire front tunnel and just refabricate it:



I went and also added into two OEM E30 mounts on the front subframe. I decided on this location based off of the
Classic Daily K24 swap video and some cad models posted by a guy on the 2002FAQ forums who is also doing this swap.



I also ended up removing the OEM engine mount pad on the subframe.

 

glad to see some action on this project.  I've got a 914 that I'm planning to k-swap sometime in the future.  

After doing all that prep work it was time to put the K24 in the 2002 and see how things fit.

Its hard to see in this picture but the water pump thermostat had a minor interference with the OEM steering box
engine mount.





We also found that the battery box was kind of bothersome when putting the engine in and out so I ended up removing it.
We ended up also removing a bunch of the engine accessories with the intent of making the fabrication of mounts easier.



Managed to get the engine in a location that I liked. The hard part with the K power pan on this car is that there isn't
a lot of clearance to the front swaybar.



The biggest issue I'm facing at the moment is that the center steering drag link hits the adapter and is right where the
transmission will need to go.



I am I'll have to fabricate some sort of curved steering link which would put the drag link in front of the adapter, such as what this
BMW E12 part:

BMW E12 link on Ireland Engineering


 

In reply to Lof8 - Andy :

Oh that sounds like it would be fun!