'72 Restomod

Let's see, what have I been up to?
The differential (3.64 open) felt funny to me. When you turn the flanges opposite directions, you could feel the spiders gear teeth rolling over each other with some pressure. Never saw that on a diff before, didn't seem normal. So I discovered Pete's Gear Shop through this forum, and called him to ask about a rebuild. After I described the problem, he said that's totally normal for these, there is some preload on the spider gears. He agreed it isn't normal for any other diff. Very nice and helpful guy, and his rebuild prices are good. So I took his advice to leave it alone, and instead just put new output shaft seals in it and painted it up.
I also put new boots on the CV axles. I got smart this time and had my local engine shop cut the old boots of and put them in their jet washer so I didn't have to deal with any old grease at all. Still got new grease everywhere, but that's a lot easier to clean up.
I rebuilt the newer style power steering pump with the kit from BMW. Pretty easy to do, except for removing one little snap ring. It's the kind with no holes in the ends for pliers. Discovered the 524td pulley on the power steering pump I used is not the same as an M30 one. Had the wrong offset. So I managed to find the correct pulley used from a friend.

The wrong pulley. This one fits the diesel as well as M20's.


And the right pulley.


I also discovered that the M30B35 has an overdrive pulley for the AC compressor. I guess to make up for the larger interior volume of the E34 and E32 while using the same old compressor from E30's and E24's? I dunno. But I didn't see any logic in running my AC compressor faster, especially since I went with the Sanden 709 (more flow than the 508) on a car with a very small interior. So I changed that to the M30B34 pulley as well.



Been doing lots of work on the wiring... I'm going to examine every inch of the harness and redo any suspect connections, fix every previous modification, and add all my new circuits into the old harness before rebundling the whole thing with PET sleeving instead of tape. I learned a couple of useful things... The front end of the harness is actually detachable from the main one. There's a dozen or so spade connectors, one molex connector to the gauge cluster, and a connector to the dimmer switch.

Front and main harness separated


I also learned you CAN remove the entire harness from the car. The part that goes to the trunk goes through some veeeery small holes. At first I thought they must have put the terminals on after it was snaked through. And they might have, but it fit back thorough. Reinstalling it will be interesting. Not as easy to push a rope as to pull one, and I'll have added an extra wire or two.

All stretched out on the floor


Just like unwrapping a 4000 year old mummy
 
Finally got my powder coating back today after waiting like 3 weeks. Had the valve cover, power steering tank, and an E28 air cleaner box done in satin black.



 
I'm working on a box to house all the relays and fuses and wiring connections I'll need in the engine bay. Back when these cars were new, it was typical to have "indoor" type connectors mounted "outdoors", as with the 2 relays mounted on the fender. And you could reasonably do the same with all the new connections I need, and it would probably work for a long time. But you'd never see that on a new car, and I'm looking for new car reliability here. So since the battery was already moved to the trunk I took advantage of that space. Could have probably mounted the box right onto the battery tray, but it had already been removed, so I'm making some brackets. The box itself is a "nema enclosure" used in industrial electrics, not anything made for cars. They only come in unappealing shades of grey and tan, so I painted the box black. Here's the exact one I got: https://www.polycase.com/yh-080604 There are many shapes and sizes, many cheaper than this one, but it was the only one I could find the perfect size. The boxes have some rails in the corners probably made to hold PC boards or something, so I used some 1/16 black ABS sheet inserted into those rails to mount my relay sockets etc on. There will be a cover between the relays with an 8 circuit fuse holder mounted to it. The horn and high beam relays that used to be mounted outside will be included in the box (I removed the original mount for them), along with added relays for the low beams, aux driving lights (2 relays for these since I'm wiring them to a momentary push button), and high and low speed electric fan. That's 7, so there's 3 extra sockets for whatever else. In the inside photo you can see 2 auto resetting circuit breakers for the electric fan (30 amp) and power windows (20 amp). I figured with those two circuits it would be nice if they came back on after an overload without replacing a fuse. Power for all this comes directly from the starter post with an 8awg wire. The forward part of the original wiring harness will go into the box and basically get chopped off there, and I'll re-make everything from there forward to the lights etc. Two reasons for that, going into and back out of the box requires extra length, and the front part of the harness to the lights was already damaged, repaired, and damaged some more so it's worth going with new wire.



 
Here's my bracket setup. I tried to use existing holes (only had to drill one).




The main reason it isn't pushed all the way forward is so that the lid can open wide and stay open on it's own.



Forgot to mention I finished the fan and condenser install. Here's a bracket I made to mount the low speed fan resistor. Since the resistor gets hot and the fan is all plastic I needed a way to mount it in the airflow stream without risk of melting the fan housing.


I started wiring up the power window relays with the 3 amp diodes that are recommended. The insulation on the diode legs is just stripped off of some wire. I didn't have any other small tubing available. It takes 3 hands to put the terminals on this way, but somehow I managed.

 
Almost forgot! Received the World Upholstery carpet set this morning, just 8 days after ordering. Looks very nice! This is their "import loop" carpet. There's close to 20 pieces and no instructions, but I'll figure it out.

 
I haven't been keeping up here... there's so much to do that isn't interesting to look at. I've been dealing with some surprise floor rust I discovered under the sound deadener. Not bad at all for an E9, but still something to deal with and it's holding up installing the wiring harness.

After months of contemplation, I finally came up with a cable accelerator that I'm proud of. Just a simple lever, the same as any cable operated one in existence. The key is creating a pivot point lower down than the original one. You can't get enough action on the top lever if the pivot is so high up. I made a pivot that bolts onto one of the pedal box bolts. I decided to use an E21 cable on the basis that it uses a hook to attach to the lever instead or the rubber grommet that E30, E28, E34 etc use (when the grommet eventually fails, the cable falls out). I think the E21 cable is going to end up being a problem on the engine end though, should have looked for an E12 or something M30 powered that might still have the hook. Easiest option is probably just to use the grommet style from an E28 or E34. The grommets don't fail all that quickly. Then you just need a round hole in your upper lever instead of a hook on it. I tested all this to make sure it does not interfere with the heater box. I'm not sure you could do this job with the box in place, but there is no interference once the box is reinstalled.

The general layout.
080D6FAA-4489-4101-9A3B-EA8A34531555_zpsns4qmfbi.jpg
080D6FAA-4489-4101-9A3B-EA8A34531555_zpsns4qmfbi.jpg


The pivot point, cut from a SS square tube.


Cut and bend the original accelerator lever. I increased the 2 bends to offset the rod more to the right.


The finished lever. The upper and lower levers are welded to a short piece of 1/2" OD tube that fits some small bronze bushings on the inside. It pivots on a 1/4" shoulder bolt. (never make anything pivot or rotate on the threads of an ordinary bolt, it doesn't work well).


The top lever is just some scrap metal that I cut into an exact copy of the E21 hook.


Cut a square hole to accept the cable.








 
Everyone except me probably already knew this, but the clear lenses for the front corner lights from Rogerstii don't fit over the US reflectors. It was just a simple matter of cutting the reflectors down (I took off 7mm). Then because they show through the clear lenses and are ugly yellow plastic, I painted the backs of the reflectors silver.









 
The owner of the car had this light mounting bar made already and I mounted some Hella driving lights to it. The bar is aluminum and very light. Looks very good I think!



Oh, and I got tires put onto the new Coupeking Alpina wheels



Some ebay valve stems I had on hand. They look real nice, but I'd try to find better quality next time. One of this 5 piece set was unusable.


 
More pictures! Installed the bumper, taillights, and a custom plate mounting bracket the owner had made with LED lights. No, the car is not registered as "machinery", I just had a plate from my generator to test out the lights with.






Since I have the AFM attached to the valve cover like an M30B35 engine, I leanred I cannot use the B34 intake boot. The AFM is in a slightly different place making the boot too short. There's only one car that uses a B35 with this type of air cleaner, and that's the 88-89 E24. So I had to get the boot for one of those. Much higher priced of course, around $45.






The new front corner light gaskets from BMW do not fit at all! After some trying to make them fit, I just cut about 10mm out of the middle and glued them back together.





There was a rusty spot above the subframe mount. I thought I would just drop the subframe and paint over it, but it turned out to be much more than I expected. The floor is actually rusted out, and the rusty part left visible is the reinforcing plate above that inside the car. So I removed the reinforcing plate and am replacing the floor below it as well as the side wall that makes up the inner rocker.



This area had a patch screwed on over it.








Here's my scheme for realigning the reinforcing bracket the same as it was. Cleco fasteners.



This part of the car is 16 gauge steel (probably 1.5mm actually).
 
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Gary Knox said:
Layne,

What did you use for the boot from the front of the air cleaner to the fresh air duct on the body? Looks good!
Click to expand...

That's just the stock piece from an E28. It's thin plastic, not rubber. I shortened the metal pipe going into the airbox as much as possible. The downward angle of it isn't ideal, but the boot seems to bend enough. I'll probably put hose clamps on it.
 
I finished the repair to the subframe mount area. Got the subframe, diff brakes, etc all installed. Installed an additional fuel line while the subframe was out alongside the original (new one is now for delivery and old one becomes the fuel return). I learned the diff mounting bolts are pretty hard to find if you don't want to pay $6/ea from BMW. M12x1.5 is a fairly rare size and I could only find them in class 8.8 (probably fine, but I prefer to use 10.9 for everything, especially something like this). Then I discovered VW part # WHT003468 A perfect size bolt in class 10.9 and it even has a flanged head. Cost under $1.50 if I recall. The only problem with those, the heads are 18mm! I hate using 18mm (or 12, or 14, or 16) anywhere on a BMW.

I did smooth out these welds and patch the area to the right, but I don't seem to have photographed that.














Found a couple small cracks in the parking brake area of one rear rotor. Maybe it was driven with the parking brakes on? Decided it was best to replace them, but BMW has no rotors, not even in Germany. Found some from Mesa Performance, but I believe he said it was the only set they had.



With that all done I went back to some minor rust in the rear floorboards. I had already welded up some holes in the fronts but got distracted with the subframe area. Made a little panel that I cut in half to patch both of them.













Now the floors are all done. I got dynamat and insulation installed today and can get back to putting the wiring harness back in.
 
Would you figure you cut 50 thousands off the quench?
 
sfdon said:
Would you figure you cut 50 thousands off the quench?
Click to expand...


Took me a minute to understand the question... The cylinder head work was a long time ago! I'd say that's about right. I went from slight contact to a minimum clearance of .040. Due to the piston being a dome shape, and my head modification being a cone shape, the actual clearance is slightly varied.
 
Photobucket is becoming outrageously hard to use because of all the ads... and my posting here is suffering because of it. But I'll forge ahead. I had my mother sew a headliner for the car when I was home for Christmas. Without a sunroof, it's just 4 long stitches in a big sheet of suede fabric. Easy for her, but more than I can do with a sewing machine. Clipped it up temporarily waiting for me to glue it. Already looks great. I got the material from here: http://www.yourautotrim.com/imausubl.html



I made a giant sized to-do list to keep me on track better :)



I did loads of work on wiring to integrate the new relay/fuse box and engine harness connector with the old front end harness. Once plugged in, everything worked the first time and nothing melted.













 
Finally got around to modifying the M30B35 pulley to fit the 3.0 water pump. Probably could have just found a 3.0 pulley, but this worked.



Also got the whole cooling system hooked up. Not much to photograph there, but I had to learn that you need the 1982-only E24 lower radiator hose to connect a motronic engine to a E9 radiator. I used E28 hoses for the three small ones that return water from the heater branch to the coolant tank. And E9 hoses for the supply to the heater from the head and the top radiator hose. Speaking of the heater, I took it apart to refurbish before installing, and learned about its peculiar operation, never shutting off the hot water supply to the core. That combined with the rotten rubber on the flaps, would easily make it feel like the heat is on all the time. So I replaced all the rubber on the flaps with some 1/8" closed cell sponge rubber from a local gasket shop, and devised a shutoff for the heater's water supply. I read Rob Seigel's heater bypass threads, and his theory that it's better to bypass the core than to shutoff the water supply, but I don't agree, for two reasons. 1) Every other M30 powered car has a shutoff valve on the heater and does not overheat. 2) The water that is bypassed travels back to the intake side of the water pump, not to the radiator. There is no net heat loss by bypassing water from the back of the head to the water pump inlet. So I proceeded with the shutoff scheme. I found a suitable valve, and made a custom cable that connects it directly to the heat slider on the dash. Then zip tied the old heat control flaps into the full hot position (so all air flows through the core rather than around it). Once my system is proven, I plan to make more of these cables and sell the setup to you guys. You might notice that I switched the heater core inlet to the top pipe. It fits better that way, and doesn't make a bit of difference. The water flow through the core is side-to-side, the physics of hot water rising play no role here.





 
Finally got around to modifying the M30B35 pulley to fit the 3.0 water pump. Probably could have just found a 3.0 pulley, but this worked.



Also got the whole cooling system hooked up. Not much to photograph there, but I had to learn that you need the 1982-only E24 lower radiator hose to connect a motronic engine to a E9 radiator. I used E28 hoses for the three small ones that return water from the heater, and branch off to the coolant tank. And E9 hoses for the supply to the heater from the head and the top radiator hose. Speaking of the heater, I took it apart to refurbish before installing, and learned about its peculiar operation, never shutting off the hot water supply to the core. That combined with the rotten rubber on the flaps, would easily make it feel like the heat is on all the time. So I replaced all the rubber on the flaps with some 1/8" closed cell sponge rubber from a local gasket shop, and devised a shutoff for the heater's water supply. I read Rob Seigel's heater bypass threads, and his theory that it's better to bypass the core than to shutoff the water supply, but I don't agree, for two reasons. 1) Every other M30 powered car has a shutoff valve on the heater and does not overheat. 2) The water that is bypassed travels back to the intake side of the water pump, not to the radiator. There is no net heat loss by bypassing water from the back of the head to the water pump inlet. So I proceeded with the shutoff scheme. I found a suitable valve, and made a custom cable that connects it directly to the heat slider on the dash. Then zip tied the old heat control flaps into the full hot position (so all air flows through the core rather than around it). Once my system is proven, I plan to make more of these cables and sell the setup to you guys. You might notice that I switched the heater core inlet to the top pipe. It fits better that way, and doesn't make a bit of difference. The water flow through the core is side-to-side, the physics of hot water rising play no role here.





 
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Layne said:
Photobucket is becoming outrageously hard to use because of all the ads... and my posting here is suffering because of it. But I'll forge ahead.
Click to expand...

I personally find Photobucket unbearable. Or any ad driven hosting site for that matter.

To me, the best option for including photos in a thread is to use the "Upload a File" option at the bottom of the message window. This uploads the photo straight from your computer or phone to the e9coupe server. You never have to deal with those other sites.
 
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