Ringy Dingy

I have been putting together the piston, ring and pin kits. Then weighing each part individually in preparation for a full balancing of all reciprocating weight. During this process I began to admire the oiling rings that came with the vintage racing pistons we acquired. At first I considered using the oil rings from that set in leu of the ones from Total Seal. They sure looks the part. Its of a 1-piece design and beautifully machined. However it weighs 15 grams to the Total Seal 3-piece ring set's 8 grams. Plus after slipping it into the cylinder to check fit it appears like it would drag a lot more and rob valuable horsepower on top of being heavier. Its such an interesting piece I thought I'd share a pic or two even if I'm not using them. The 3rd set of oil rings is a 4-pice design and from the pistons I pulled from the motor. They weighed in at 10 grams. Oh, and I almost forgot the piston pins. I had 2 sets of these as well. A set from the pistons that were already in it and the other are from the Mahle racing pistons. Only 1 of the four was a gram lighter. The other three were exactly 105 grams. Guess I won't have to do too much "balancing" after all...

Soda blasting

We picked up a blast cabinet a while back and rigged it to run with the soda blaster. Worked great for de-carboning the heads after disassembly. Also noticed to large steps in the ports and look forward to "porting" these guys soon.

Where did the time go?

I told several people I would be finally putting up a new post last month but my software for retrieving photos from my camera went south and I didn't want to post anything without a picture. Anyway here's a quick pic of the cylinders after paint. Its designed to better dissipate heat and was done by Applied Plastic Coatings in Wheat Ridge. More updates will follow soon.

Frenching the rear emblem(part 2)

Tomorrow turned into today, and today turned into last week. Anyway, I got a 68mm hole saw from Home Depot, drilled a pilot hole dead center and proceeded to cut a hole in our new(to this car) deck lid. The O.D. of the piece I'm welding in almost 70mm, so I had a little room to fudge it if the hole wasn't dead center. And what do you know it was off a tiny bit. After some measuring and hand filing I had it dead center and ready to weld in place. In these pics, you mat notice that I also welded up the rear facing part of the lid where the license plate light used to be. I decided that it looked way better without that chrome trim/light piece at all, and removed it. I'm not going to be running the license plate there anyway. Hopefully I'll be back soon with part 3, welding and grinding the part in place.

Frenching the rear emblem(part 1)

I really like the look of the rear on cabriolet 700's. They have only a BMW roundel on the decklid and none of the extra badging the others use. I decided to "french" the emblem into our lid in the same spot as the cabrio. I started with a DIY exhaust megaphone, and a hand cut piece of 18 gauge sheet in the shape of a circle 1mm larger than the roundel. I centered the roundel in the circle, centered the circle in the tube and then welded it. I removed the excess tube, ground down the weld and now have a piece that is ready to be welded into the decklid. Tomorrow I'll cut the hole in the lid, weld in the piece, and grind it all smooth. The current depth is about twice what I have planned as the final depth when done.

Brake master cylinder

Today I rebuilt the master cylinder for the brake system with a kit I got from Germany a while back. I started by degreasing the body and knocking off the rust with some 100 grit sandpaper. I lightly polished the exterior of the cylinder on my bench buffer with a spiral pad, leaving most of the sand casting pits to give it a shiny but cast appearance. I heavily sanded and polished the forked piece and pin that connect to the brake pedal. I am planning on having carpeting, but will be leaving the pedal box exposed, so I needed these pieces to look nice and shinny. I then etched the inside of the cylinder with muriatic acid and cleaned it with a rolled up scotch brite pad. Next, I thoroughly rinsed all the parts including the new rubber bits from the rebuild kit in warm soapy water. I blew it all dry with compressed air and started the rebuilding part. Assembly was a breeze, even with the German language instructions. The only part I re-used was the rubber boot on the top where the reservoir feeds the cylinder. Unfortunately it did not come in the kit. Afterwards, I covered the ports in masking tape to keep debris out and put it in the done pile.

Paint it black

Just picked up some suspension parts at the powder coater this afternoon. Rear springs, sway bar and sway bar brackets.