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Steve Huck, Sterling Heights, MI firstname.lastname@example.org
Chevy V8.(kinda) CO2
This is a spinoff of the V1 David Kerzel project. It is 1/4 X 1/4 with 8 cylinders. Hopefully it will work and stay together. The tough part will be making a crankshaft strong enough. The plan is to press together Crank parts around bearings and capture the bearings between the block and oil pan. When finished it should resemble the Chevy V8.(kinda) About 50% of the parts will be non-functional so that it will look better.
While you are at it, can you mark the "Chevy V8 kinda" finished. Here are the photos of the finished project. Folks are writing wondering when I am going to finish.
N.A.M.E.S. was great! Sorry Gail but the HOSC did'nt place but I did get 80 votes that netted me an extra $80
First in class. (Sherline Challenge)
Third over all.
480 bucks in prize money.
These are the crankshaft modules. There is a crank disk with a pin on it and a crank disk with a hole in it. There is a 11 X 4 X 3 mm Bearing that slips on the disk with the pin and then the other disk is pressed on to capture the bearing. Then the hole is drilled for the crank arm and the rod is pressed into that hole. There is .0015 to .002 inches interferance and the side with bearings were put in the freezer.
The eight holes in the other side and the holes in the flywheel disk are .0625 and are a nice snug fit.
I drilled the Disks every 45 degrees so i can adjust the firing order to experiment.
With the oil pan on, The crank turn very nice and the pins are nice and tight.
Pistons are done though 3 of them are a bit to tight. I may have egged them when I pressed in the wrist pins (easy fix) . I'll get the lower end moving smooth and then I'll start on the ball seats.
I got to thinking that I could sleeve the bore with some bronze tubing and then make drill rod pistons. If these wear out or I make another one, I may try that just to see if it works.
Well it should run as soon as i get some fittings and a regulator to get some air to it.
I made all the seats and parted them off a bit big. Then i put all the seats in the mill vise at the same time and milled them to .113 so they were as close to the same as i could get them.
Took about 65 Lbs of air but it ran. Sustained run for about 45 seconds before the air compressor ran down. This thing uses alot of air. Sounds pretty cool. I had to add a bunch of screws down the air rail to stop the leaking. I also put a cheater chunk of steel on the flywheel and it runs longer tho it runs not bad without it. Getting the pins in the pistons the proper length is a bear. Now it's time to dress it up!
First off. . . Merry Christmas and a healthy new year to everybody. We are getting some substantial snowfall so I made it to the shop.
Now that the micro V8 is in running condition, (see video), it is time to make some of the cool stuff. Here are the valve covers with the breathers.
Video link on YouTube : http://www.youtube.com/watch?v=N2cCYrqq6fU
That was running at 60 - 70 lbs. When you say tight, what kind of piston clearance are you talking. I made these .246 - .247. I thought that would be loose so it would run at lower pressure. I think the lower running pressure would be easier on the crankshaft parts.
At first I had problems with the pins in the pistons being too long. That might have something to do with one of the crank pins coming loose. All the other crank pins are still tight. If I were to do it again (and I will) I would do the crank disks with drill rod instead of bronze.
It was hard to tell where the leaks were so I made a test fixture to check the seats. They were all good. I reground all the piston pins to closer to .010 and that was the first run. Surprised us both.
I now have drawings for a double size V8 that will use a camshaft to lift the balls off the seats. That will allow me to lift the ball higher and longer after TDC. I think it will run smoother and with allot less pressure. If it works I will try to convert the micro to a cammer.
Video is on the way!
Taken today. Note the alternator and pulley.
You can poke the ball with a piece of .032 wire from the bottom.
Copyright 2007, Florida Association of Model Engineers and engine builder as noted above, All rights reserved.