Project Armo "330i" M-tech 1

[Skarpa]

For the strut tower braces I planned to use 33,7 x 2,0 or 2,6 pipe. We don't have such at work but insted we do have 33,7 x 3,5 zinc plated pipe. That's way too thick walled and heavy for this application and the zinc makes for nasty welding but luckily we have a lathe.


This didn't make much sense except that the pipe was free and I like metal turning:p I started fitting the pipe. It's a bit complicated fit with both of the pipe ends notched. As usual in this kind of cases, once I had both ends figured out the pipe was too short. I taped some cardboard in one end of the pipe and marked the shape on that.



Then I wrapped paper around the pipe and cut the ends in the shape of the pipe. Then I slid the paper cylinder off the pipe and onto a new one and it was easy to mark the shape for the ends.


I should have a ready pattern for the driver's side when I just wrap the paper inside out.


The bottom end of the pipe is slightly open allowing any condensed water to run out. At work they've told me that it's important to leave drain holes in hand rails and other closed pipe structures.



Next I had to think about how I want to join the pipe to the frame beam. to make it even sturdier. This is what I came up with:




Initially the plate went all the way to the bottom corner which provided stronger shape consisting of two triangles but then I lobbed off the bottom corner to avoid creating a pocket that collects dirt and water. It should be pretty strong even without the corner. The hole is screaming for a dimple. We'll see what I can do about that.

[Skarpa]

I finished assembling the front struts. The old front brake discs were in such a good condition that I just removed any surface rust and gave them a lick of paint on the centers and edges.

[Skarpa]

Random small stuff that I've done lately:

I blasted the diff rear cover with glass beads to get rid of most of the grime and oxidation. Before:


After:

Probably pretty useless thing to do since the part will soon be just as oxidized again but it's nice to see it clean for once. I may give it a lick of lacquer to keep it tidy slightly longer.

Next I prepared the hydroboost reservoir for zink chromate plating. There's a brass(?) sleeve at the bottom of the reservoir and I'm douptful of how well it would handle hydroclorid acid. I tried to see if I could take the reservoir apart but found no way.


So I decided to only treat the outside of the tank. The lid has a breather and I wanted to treat the lid separately so I made a temporary lid out of steel plate and sealed it with rubber and sealing compound. The hose connectors I joined together with small lengths of hose. Should be watertight now.


I also went through the rest of the parts to be powder coated. I masked alla the necessary areas and marked the color code on every part. Now I have pretty much everything ready for powder coating and zinc plating.

[Skarpa]

Nice progress! Stiffening mods look good!

Thanks!

Did you not look into the cabrio reinforcement pieces?

Yeah I did. It would have been possible to achieve similar stiffening effects using or copying the E30 cabrio reinforcement pieces but I decided to do it this way. My tubes will go directly from the A-pillar to the strut tower cutting out the middle man. I suspect that the cabrio upper frame beams are quite a lot sturdier than the sedan ones. Also, some of the cabrio pieces are already NLA. I will do some gussets to tie my tubes to the body and the frame beams and may also do the cabrio style strut tower pieces.

I dislike strut bars because they cramp up the engine bay. With these modifications I believe to achieve at least equal stiffening effect. And more so since a strut bar doesn't give any vertical support. (the last point not related to the cabrio reinforcements)

[BUDNUNTA]

Did you not look into the cabrio reinforcement pieces?

[alistairolsen]

Nice progress! Stiffening mods look good!

[Skarpa]

It's been a while since the last time I had time to work at the garage. Yesterday I got quite a lot done though, not all shown in this post. I finally welded on the bracket for the glove box


Also, I tidied up the weld seam on the wheel well side.


Once the welds had been cleaned I started thinking about additional bracing for the strut towers. Reinforcing or stiffening the body has not been my main priority in this build but I've done some stuff that seems well advised and corrects some inherent design flaws in the body or the chassis such as switching to E36 diff rear cover and reinforcing the cross member that supports the rear of the diff. Petrolhead has well rationalized the need for additional bracing on E30 front struts. E30 is missing the diagonal frame beams that go from the bottom of the A-pillar to the strut towers. E34, E36 and all the later BMWs have this structure. E30 strut towers are well supported on the inner edge but on the fender side the structure is flimsier.


E36, see the sturdy diagonal beam.


E30 has a bit similar structure but the diagonal shape is at a very slight angle and attaches to the A-pillar quite high up. This doesn't create very strong triangle shape. Petrolhead added tubes going diagonally from the A-pillar to the strut tower in his ultralight project. I decided to do the same and maybe refine the shape a little bit. The tube will go something like the ruler I'm holding. The idea is to brace the strut tower vertically and provide some sideways strength as well. I set a few rules for the tubes: They should not take any space from the wheel or hinder the plastic inner fenders in any way. I also wanted to keep the tubes straight with no bends or dents. These rules dictated that I needed to take the tubes through the body.


In this pic I'm using a vacuum cleaner pipe as a placeholder for the tube because I didn't happen to have correct size tubing at the carage. I was thinking 33,7 mm x 2,6 mm. I made a hole for the tube through the side of the foot space, through the fire wall and through the top of the wheel well.





I'll weld the tube on the side of the strut tower and A-pillar and will close all the holes around the tube by welding. It would have been quite a lot easier before I closed the battery shelf area but oh well...


The inner fender fits fine and the tube isn't any closer to the tire than the corner of the original battery shelf.


As I didn't have suitable tube I couldn't progress further so I used the rest of the time to make a cable holder for the right front ABS sensor since my car didn't have one.

[Skarpa]

For a while I've been following IronJoe's M3 cabrio project and the air deflection plates at the rear catched my eye. Before that I didn't know M3 had this feature. The plates make sense because the rear valance and rear bumber are like a huge umberella or a parachute at the end of the car creating drag and probably also lift.



I haven't compared the M3 and M-tech 1 rear bumbers or skirts side to side but looking at photos I think the bottom edge is pretty similar and in pretty much the same location. The M3 rear bumber bottom edge might be a couple of centimeters lower. I'm pretty sure these plastic parts would fit the M-tech 1 as well with slight modification. They seem to be about 150 EUR for a set.

Otherwise I haven't really had time to do much but look at some pictures online because my busted knee, wife's busted wrist and stomach illness all around has made the life pretty interesting for our small family lately. But here's some small stuff:

I ground smooth all the welds for the fire wall section, made the pass-throughs for the cables and primered all the areas that will be later hidden with weld through primer.


I went through all the rusty spots in the front valance with a wire brush wheel and phosphoric acid and protected all the bare parts with primer.


The throttle pedal linkage got some paint as well.


Also, as a small slip up I bought a complete Zender body kit when it happened to be available for a decent price. Actually it was not a complete kit when I bought it. I happende to see the valances and skirts for sale and at the same time another guy was selling the trunk lid spoiler:





This pic is not of my own parts. The trunk lid spoiler is in original packaking. It has been bought in the nineties but never been mounted. Then rear valance is the same as in the picture but a one-piece unit.


Also see the dashing Testarossa -style side skirts :D. Behind the car there's a Pfeba rear valance that I was considering to pair with the Zender kit because in my opinion the bottom edge of the Zender rear valance is just too high up.

I'm still mulling over this body kit business. I have a couple of options: install the Zender kit and keep the tech 1 kit on the shelf. Install the m-tech 1 and keep the zender on the shelf. Or just sell the Zender kit and get on my own or preferably make a small profit since it's a complete kit now. Selling the M-tech 1 kit is not an option. I like the Zender kit but the parts are in a rougher condition than the M-tech ones and it would take a bit more work. Also, if I decide to go the Zender way I think I'll need to find a way to lose the bumber trim because there's no side trim either. (For example do something along the lines of M3 bumbers without the fender flares) I just may be that with the available budget and hobby time I'll sell the Zender parts and continue with the M-tech 1.

[Skarpa]

While I've been sorting out parts for painting I've often laid my eyes on the S50 plenum. The paint was chipped and discolored and there were a couple of major scratches. The plenum is sand casted and it's been painted over without sanding leaving a distinct rought finish often seen in BMW Motorsport engines. Repainting the part while retaining the original finish would have bee nigh impossible especially if I'd wanted to fill the scratches. On the other hand, why go through all that trouble when I have nothing else with similar texture in the engine bay? So I decided to take an arguably even more arduous route: Sand the part smooth with an orbital sander.









It took a full days worth of work but eventually it was done. I'll have the plenum powder coated in gloss black. It should go along nicely with the gloss black valve cover.

[delamaize]

I read through your project thread. Looks cool! Also, the 3-piece bottlecaps would definitely fit the car.

Thanks Man. I have been following your build for a long time, You're work is pretty impressive. I look forward to seeing it finished!

[Skarpa]

Those wheels are absolutely sexual.... I'm envious of your abilities!

Thanks! At the moment the TRX wheels aren't much else than an idea in the air and some pixels on the screen but my goal is to eventually build a nice set of wheels that go along with the diy nature of project Armo. Hopefully I can create in reality what I've envisioned on the screen.

[Ryan...]

Those wheels are absolutely sexual.... I'm envious of your abilities!

[Skarpa]

This is what I used. And it works great.

http://www.bimmerworld.com/Gauges-Da...ing-Block.html

Yeah, I had a look at that but it seems to me that the distribution block is kind of a dead end. Wouldn't a sensor mounted in the distribution block measure the temperature of oil sitting there rather than the oil going into the engine if there's nothing that makes the oil flow past the sensor? Might be it still works fine if oil happens to form suitable turbulence that flushes the distribution block.

I don't mind having the temp sensor in the oil pan. In the level sensor it is in the middle of the sump and near the oil pickup so the temp reading should represent quite well the actual oil the engine is getting. The reading might be slightly different than in a sensor mounted at the filter housing but mostly I'll be interested in changes in oil temperature over time in different conditions.

What I don't want to do is mount the sensor at the drain plug because I feel it would be too close to large heat mass of the oil pan and would not have proper flow around the sensor.

[rzerob]

This is what I used. And it works great.

http://www.bimmerworld.com/Gauges-Da...ing-Block.html

[Skarpa]

I revisited the oil temp gauge project for a bit and learned some coding. I scaled the needle movement to my temp scale. There's a slight discontinuity in the needle movement where the coils change their polarity so I took that into account.



I'll just need to buy a sensor for the gauge and write some code for temp measurent. There's no good place for a sensor at the oil filter housing so I'll use an oil level sensor with a temp sensor in the oil pan. (Hella P/N 6PR 007 868-031)