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 Post subject: BMW based build
PostPosted: December 10, 2020, 8:01 pm 
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Joined: October 26, 2020, 11:24 am
Posts: 43
Location: Mineral, VA
The usual lurking, reading, staying in the background applies to me as well.

Good, that's over with.

I acquired this donor over 10 years ago, but didn't have the physical space to take it apart, nor the means to build my Locost.
1975 BMW 2002, 4 speed manual, IRS. I went with the 2002 based on the price to buy it (not much, body is SHOT), and the fact that it's a carburetor fed, distributor ignited, manually shifted car. Independent rear is a bonus, and a hindrance, as we'll see in the build.

With no further delays, here we go!

Attachment:
Engine in bay resized.jpg


So, little did I know that the engine and transmission DON'T come out of the top of the bay, but the bottom. Success would elude me for just a few hours (actually days because I get only a few hours in the garage after work and household duties are completed to the satisfaction of the Kaiser.

Attachment:
Engine and trans out resized.jpg


After many head (and other key areas) scratching, the engine and the transmission were no longer together. About 59K showing on the odometer, and after disassembling the engine, it was pretty accurate. No ridge in the cylinder walls. At all. Knocked the head off, and the pistons dropped out. Here's what it looked like without the head on, and pistons still in the bores. What I didn't know was that the difference in compression between Cylinder 1 and the other 3 would cost me.

Attachment:
2019 06 12 Engine before machine shop resized.jpg


After saving what I could, by whatever means (we have TWO kidneys, who knew?), I had enough to send the block, head, flywheel and assorted bits off to the machine shop. Head was in great shape, rods checked out, and the crankshaft didn't need turning just polishing. The block was another story. Cylinder 1 was rusted and pitted, but the other three were in great shape, and I while I knew that I couldn't just hone it out, I didn't realize it would take .030" to get it right, so I had to order custom pistons.

Attachment:
2019 08 31 Engine after honing, boring, decking resized.jpg


Attachment:
2019 10 13 Piston resized.jpg


So I buttoned up the engine, covered it with a sleeping bag, and got to work on the frame.


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BMW 2002 donor, M10 motor, 4 spd trans, IRS, tube chassis.
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 Post subject: Re: BMW based build
PostPosted: December 12, 2020, 8:19 am 
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Joined: October 26, 2020, 11:24 am
Posts: 43
Location: Mineral, VA
I liked the idea of using square tubing, but that's a lot of cutting and welding. So, I did something different: bent it. Got a bender, built a work table and started to bend metal. Measure once, mark it with a grease pencil and cut as many times as needed to fit, right?

Attachment:
2019 12 19 Bender mounted resized.jpg


Attachment:
2020 06 14 Build table beginnings resized.jpg


I wanted to bend the whole lower portion of the frame in one shot, but, I'm not that good. No where near that good. So I split it into two halves, length-wise.

Attachment:
2020 06 24 lower frame half resized.jpg


Got the other side bent, and welded the two together. I'm using 1" x 0.120" wall metal. Heavy, yes, but I got what the bender would bend without kinking or collapsing the wall.

Attachment:
2020 06 25 lower frame halves joined view 1 resized.jpg


Attachment:
2020 06 28 upper frame rail resized.jpg


At this point I realized that the upper I bent wouldn't work, so I made another one, just like it, but more better. Sorry, no pics of it. Time to make 2 into 1!

Attachment:
2020 07 05 setting upper rail height resized.jpg


Got a few braces installed on the two-now-one portion of the frame.

Attachment:
2020 07 05 upper and lower frame tacked with bracing resized.jpg


So, knowing I'm made of more squishy bits than the car is, I figured I'd need some reinforcement on the rear of the passenger compartment.

Attachment:
2020 07 19 rear bulkhead additional bracing resized.jpg


Attachment:
2020 07 22 rear bulkhead bracing finalized resized.jpg


A few more pieces, and the frame is ready for the suspension bits and parts to be added.

Attachment:
2020 07 28 frame side view resized.jpg


Stay tuned! See if he can continue the build with minimum self-destruction! More JackFrost action coming next week!


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"If it's broke, fix it. You can't make it more broke"

BMW 2002 donor, M10 motor, 4 spd trans, IRS, tube chassis.
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 Post subject: Re: BMW based build
PostPosted: December 13, 2020, 11:08 pm 
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Location: Eastern Oregon
Nice start, Interested to see this develop. Keep up the good pictures and narration!

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 Post subject: Re: BMW based build
PostPosted: December 14, 2020, 11:11 pm 
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Posts: 43
Location: Mineral, VA
So, onto the rear end! (I've heard the proctologist use this phrase, not comforting. At all)

With the 2002 using a trailing arm suspension attached to a large cross brace, and mounted at 4 points, my thoughts turned to attaching said large chunk of metal.

Attachment:
2020 07 28 trailing arm mount lateral brace drivers side resized.jpg


I'm not sold on the small, curved piece of metal going vertically from the arm that the cross brace is attached to, but nothing is fully welded at this point, just tacked.

Attachment:
2020 07 28 trailing arm mount lateral brace passenger side resized.jpg


Attachment:
2020 07 28 trailing arm mount rear view resized.jpg


More bracing! Wow, who would have guessed? But first, I had to attach the differential, which meant a custom mount for the rear cover (really, that's how they did it) and make it copacetic with the new poly mounts I ordered.

Attachment:
2020 08 15 diff mount 1 resized.jpg


So, I came up with this. Overkill, undersized? It don't move, and there's a lot more metal back there, and I have something which to attach the coilovers.

Attachment:
2020 08 16 diff mount outer bracing rear view resized.jpg


Attachment:
2020 08 24 coilover upper mount rear view 2 resized.jpg


I'm confident it will work. Had the coilovers in single-shear at first, and that didn't fly with the internal engineer (me), so I redesigned it to have a double-shear mount, top and bottom. I'll re-make the upper mounts, as they're not the same height off of the floor. They're out about 3/8" which bugs me to no end.

With the back done - for now - I move to the front end.

Come back next week for more JackFrost action. Thrills! Chills! (It's winter, after all) Spills! Well, drools actually, but only when the wife is walking around the garage... :wink:

Attachment:
2020 11 28 rear coilover mounts tacked resized.jpg


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"If it's broke, fix it. You can't make it more broke"

BMW 2002 donor, M10 motor, 4 spd trans, IRS, tube chassis.
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 Post subject: Re: BMW based build
PostPosted: January 3, 2021, 2:12 pm 
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Joined: October 26, 2020, 11:24 am
Posts: 43
Location: Mineral, VA
So, onto the front end!

Knowing the wheels wouldn't hold themselves in free space, I decided to make lower control arms that would utilize the donor's lower ball joints. So, I came up with this idea:
Attachment:
2020 11 23 LCA ver 2 in progress resized.jpg


Attachment:
2020 11 26 LCA ball joint mount in progress resized.jpg


Now, I ain't a jeeneeus, but I did recall seeing a lot of posts about getting clearance through the UCA for the coilover, and since I'm building a car to suit my tastes and not doing the logical option, I came up with the idea for a pushrod suspension:

Attachment:
2020 11 26 LCA ball joint mount welded resized.jpg


Attachment:
2020 12 11 suspension pushrod 2 resized.jpg


Notice how the LCA looks different from the other pictures? Yup, found out that I'd have easier time mounting the steering rack if I flipped the LCA's and moved the wheels back, therefore giving me more room in the future for the rack. Anyways, onto more pictures, it's why we love build logs, lots of pictures!


Attachment:
2020 12 12 pushrod suspension drivers side ver 1 resized.jpg


Attachment:
2020 12 12 pusrod suspension pass side ver 1 alt view resized.jpg


So, as soon as the Federal Express driver drops off my present to myself, I'll be able to mount the coilovers inside, and hopefully, move onto the UCA mounts and get them put into place. I did cheat and order the items to make the uppers, pictures coming soon (I know ya'll like pitures...)

Thanks for reading, and come back for more JackFrost action next time! Thrills! Vertical compression engine mounts DO NOT like being in a shear position!! Chills: heater is broken, still And spills! plenty of drool on the floor, wife came through the garage again... need a spill kit installed on the wall.


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"If it's broke, fix it. You can't make it more broke"

BMW 2002 donor, M10 motor, 4 spd trans, IRS, tube chassis.
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 Post subject: Re: BMW based build
PostPosted: January 17, 2021, 5:51 pm 
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Joined: October 26, 2020, 11:24 am
Posts: 43
Location: Mineral, VA
Good evening everyone!

In my mechanical magical journey, I have learned many a new thing, and the first I learned a long time ago, DO NOT FINISH WELD ANYTHING!

The rocker pivot for the pushrod suspension was equal on both sides, center to center. Yeah, it didn't work with the coilovers I ordered. So, I had to do a mulligan. That, or spend a lot (for my budget) more money for different coilovers and springs.

Attachment:
2021 01 07 pushrod ver 3.0 with coilovers resized.jpg


After discovering my error, I finally figured out through the help of a good, long-time friend, that I needed to have a 2:1 ratio, roughly, to make the coilovers work. As I have plenty of scrap metal pieces sitting around, I redid the pivot, and I'm pleased to report its much more betterer.

Attachment:
2021 01 10 revised rocker ratio resized.jpg


Then, using store-bought bracketry and tabs (sorry for the spelling) I located and tacked in the UCA mounts to the frame, and put the control arms in place.

Attachment:
2021 01 17 UCA situated resized.jpg


Next thing on the list is the spindle assemblies, but that's gonna take a sharp drill bit. Mine ain't sharp (Hell, I ain't sharp, but I'm building a car. Scary). But we have a bit sharpener at work and I intend to try it out. Once that's remedied, and once I've located a 7 degree tapered reamer that I can borrow, I should be able to mount the spindles, then onto the steering rack. More pictures to follow, and follow JackFrost for more thrills, chills and spills!


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"If it's broke, fix it. You can't make it more broke"

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 Post subject: Re: BMW based build
PostPosted: January 20, 2021, 5:08 pm 
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Joined: July 19, 2015, 9:31 pm
Posts: 19
Hi: I'm doing something similar. Same pistons 9.5 CR. Opel front end, BMW rear end. I put her together, and the rear end was only sheet steel, and it bent, so, back to the drawing board. I'll just try to straighten the sheet steel and reinforce it. I have a Jones for rear discs, so might go that route. The driveshaft is very short. So, it's a short BMW with an Opel front end. Did you ever consider using the front of a 3 wheel motorcycle?

Jack


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 Post subject: Re: BMW based build
PostPosted: January 21, 2021, 9:27 am 
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Joined: October 26, 2020, 11:24 am
Posts: 43
Location: Mineral, VA
nikijack wrote:
Did you ever consider using the front of a 3 wheel motorcycle?

Jack


You know, it didn't occur to me to try that. It's a neat idea, self-contained steering, upper and lower control arms with springs. I was attempting to use everything from the donor I could.

I did keep the table-top I made, it's a good idea for the next one... :wink:

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"If it's broke, fix it. You can't make it more broke"

BMW 2002 donor, M10 motor, 4 spd trans, IRS, tube chassis.
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 Post subject: Re: BMW based build
PostPosted: March 14, 2021, 9:26 pm 
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Joined: October 26, 2020, 11:24 am
Posts: 43
Location: Mineral, VA
2 MONTHS! It can't be 2 months. 2 months ago, it was cold, snowy, and ended February with ice.... Yeah, you don't like the weather in Virginia, just hold your breath, exhale and count to 15. It'll change....

So, I've been busy, but not with the car. Lockdown, restrictions, virus-related whatchamacallit, it all adds up to more hours in the shop at work, and less at the garage. Busy with customers means more hours at work, a little extra for the build project fund, but no time to work on it. Oh well, on with the show!

Knowing that the car wouldn't go very fast on the track without an engine, and, said engine needed to have better attachments than baler twine and coat hangers (I thought about it for a second), I fabbed up an engine mount from something I thought looked right from the interwebs.. and got this.

Attachment:
2021 03 14 motor mount 2mp.jpeg


Engine is in, tranny has a temporary mount. Not 100% pleased with the driver's side motor mount, and having forgotten to take pictures of it, it'll have to wait for the next update. Still not satisfied with the end results and may end up changing it as well. Again.

On to: Suspension! :BH:

I was chatting with an old friend the other day, and he suggested I change the rocker ratio on the front suspension because of something called 'mechanical advantage.' I thought 'mechanical advantage' was the benefit of having a garage and not paying for tire rotations or oil changes.

So I did. Front end is MUCH stiffer now.

Attachment:
2021 03 07 rocker bracket ver 2.0 2mp.jpg


It has a 2:3 ratio, which should work. Old ratio was a 2:1, favoring the LCA. Now the LCA doesn't budge when I lift it up, unlike before....

After this, came the front uprights/spindles. But I hit a lag, because, well, uninsulated building, bitter cold (For us. Perry and the gang can keep that stuff up there in the frozen north) and yeah, just wasn't motivated to go to the unheated playhouse. Burned a lot of wood in the basement of the house, and kept the wife happy.

Then the weather got a little better, so I had a consultion with the Reverend Elijah Craig, and figured out that if I could do those suspension parts, I'd better keep going. Wasn't going to build itself, the car was. A quick trip to the local metal fabricator, and he turned some home-designed adapters to fit into the trimmed uprights, reamed them with a borrowed 7 degree reamer, then a bolt here, brace there, add in a upper control arm from Speedway and, BOOM!

Attachment:
2021 03 07 front end view 2mp.jpg


All done before the next consultation session. Weld, fabricate, etc. before, de-brief/consult after.

And, after that progress, I wanted to see what it'd look like with the wheels on it. So, yeah... it looks like an erector set drove into a stack of tires...

Attachment:
2021 03 14 side three-quarters 2mp.jpg


All I have to do now, is get the driveshaft shortened, balanced, install new guibo disc up front, new u-joints in the back end of it, get that installed, and only a few hundred other tasks, and I might get it done before... before... well, before I can't get my stiff-jointed backside into the non-existent drivers seat. BUT, I should have the seat soon, so pedals hung after that, then the steering wheel, shaft, steering joints.... Yeah, ya'll know better than me.

Thanks for reading this far! Come back another week (not next week, inventory at the shop. Yuck) for more thrills, chills and spills (gotta get a spill kit on the wall, I'm telling ya).


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BMW 2002 donor, M10 motor, 4 spd trans, IRS, tube chassis.
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 Post subject: Re: BMW based build
PostPosted: July 18, 2021, 8:09 pm 
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Posts: 43
Location: Mineral, VA
So, for those not in the loop, our shop was designated 'essential' per our state government, and we have been wide open for over a year, hence the 4 month delay in not getting pictures posted. Typical spring time rush (sell and service handheld and outdoor power equipment), coupled with increased demand meant I didn't have the energy to work in the garage and get done what I do during the week meant it had to wait for the weekend.

I didn't fall off the face of the planet, but some days after work, I felt like I did. On with the show!

A lot has happened: Seat installed, steering wheel mounted, front suspension rethought and done almost all over twice. So, lets have some pictures!

Attachment:
2021 05 25 Seat installed, with old suspension mockup resized.jpg


Love the seat, love where it sits, love how it sits. Haven't taken the obligatory Vroom Vroom pictures yet. Open header on the motor, it'd be too loud anyway.

So, I wasn't pleased with the front suspension's location being so high, and after seeing ya'lls builds with the nice nose cones from Jack @ Kinetic, I knew what I had built wouldn't fit under one of those. Never worked fiberglass, and not really looking forward to that step either, so I decided it was time for a change.

Attachment:
2021 06 27 Revised front sus mockup resized.jpg


This relocates the springs so I can keep the pushrod setup, and it allows me to use stuff I have sitting around all ready (big plus). I'm trying to use up the scrap pieces I have left over from bending the frame. I want to toss the stuff, but little small pieces keep finding use on the car. And I'm cheap, so I hate tossing stuff out.

Attachment:
2021 07 05 Front susp tacked rear three quarters resized..jpg


The steering support is temporary, but I like where it is. I'll either add some flat metal to brace it, or add more small round stock from corner to corner to brace it up. I'm leaning towards some thin gauge flat metal, 20 or 18 ga. Suggestions?

Attachment:
2021 07 01 Front susp tacked top down view resized.jpg


I still want to put more corner bracing in, and have added more than what's shown in these pictures. Got a few more pictures to take, so let's hope the next update doesn't take me 120 days to get uploaded. Time to get out to the garage!


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BMW 2002 donor, M10 motor, 4 spd trans, IRS, tube chassis.
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 Post subject: Re: BMW based build
PostPosted: July 18, 2021, 8:32 pm 
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Location: Mineral, VA
Here's a shot of the front end, showing the steering wheel and seat located. Need to get a picture of the relocated engine/transmission. Had to shift it about 8 inches forward for comfort reasons....

Attachment:
2021 07 04 full front view with steering wheel resized.jpg


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 Post subject: Re: BMW based build
PostPosted: July 19, 2021, 11:25 pm 
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Bending the tube really looks good especially in the details. Does is come out as a mandrel bend?


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 Post subject: Re: BMW based build
PostPosted: July 20, 2021, 8:36 am 
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JackFrost wrote:
Attachment:
2021 07 05 Front susp tacked rear three quarters resized..jpg


The steering support is temporary, but I like where it is. I'll either add some flat metal to brace it, or add more small round stock from corner to corner to brace it up. I'm leaning towards some thin gauge flat metal, 20 or 18 ga. Suggestions?



A single vertical tube between upper and lower rails, with a tab or threaded tube to mount the support is all you need to keep the intermediate shaft aligned to resist steering effort. Put the tube as close as possible to the support. I said vertical but in this case it would be sorta diagonal with the wider upper frame.

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 Post subject: Re: BMW based build
PostPosted: July 20, 2021, 12:44 pm 
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Location: Mineral, VA
sony1492 wrote:
Bending the tube really looks good especially in the details. Does is come out as a mandrel bend?


Depending on the thickness of the material, yes. The difficulty with bending the square tubing is my set of dies has a slightly beveled curve on the radius of the die, denting the interior of each bend. I'm still learning how to use it, as it's strictly a manual bender. I have acquired a set of dies for round stock, and will experiment as I can afford.

Next step for the bender is to work on the roll cage. Gotta pull up the GCR specs to see what I can and cannot get away with. I want a bolt-in cage, but don't think they'll let it fly. Have to read the fine print (big print giveth, fine print taketh away....)

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 Post subject: Re: BMW based build
PostPosted: July 20, 2021, 12:51 pm 
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Location: Mineral, VA
Miatav8,MstrASE,A&P,F wrote:
A single vertical tube between upper and lower rails, with a tab or threaded tube to mount the support is all you need to keep the intermediate shaft aligned to resist steering effort. Put the tube as close as possible to the support. I said vertical but in this case it would be sorta diagonal with the wider upper frame.


Should I move the steering support rod end closer to the middle u-joint (towards the steering wheel) to help, or leave it where it is?

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