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Steve Huck, Sterling Heights, MI email@example.com 9/1/2008
PeeWee 4 Cylinder, 4 cycle
The last engine designed and built by Bob Shores. Click here to go Bob's page for this engine.
This is the Bob Shores Peewee V4. It is the famous 4 cylinder with a 5/8 bore and stroke. Having never built a casting based project, I had been looking for a casting based project to be my first. I saw Bob Shutt at the 2007 NAMES show and liked the V4 project. At the time it seemed to me to be beyond my skills. Seeing it again RUNNING at the 2008 show, I came home, tracked down Dirk, and bought the castings.
It is built using castings and plans purchased from Dirk Tollenaar. The plans are not the greatest, I am guessing because Bob passed away before getting a chance to finish the plans. This added to the difficulty of the build and ultimately the reward. I started drawing the engine in 3D cad to verify the drawings and allowed me to "fix" a few things. This lead to about 60 drawings of parts that needed dimensions, but mostly redesigned and added parts to change the looks of the engine to my liking. All things considered, I'm glad I picked this project. It has been a mountain of fun.
I don't have the gene that allows me to build to the plans. Of course this lead to the fancy motor mount system. I also made some additions like a counter balanced crankshaft, dip stick, balancer and timing pointer.
Just finished machine work on the peewee heads. If you build the Peewee, DO NOT make two heads from the drawing set. The plans show only the head for the 2-4 cylinder bank. This head will not work for the 1-3 cylinder bank. The 1-3 head is one of the things that will need to be reworked before it is machined.
I changed the plan so that Uncle Dale's (Detrich) plugs would fit. I also plunged an end mill in .125 at the port openings to help me locate the hole and to clean up the entry for drilling. Other than that, they are stock Bob!!
I have completed the valve cages. They are pressed in and ready to go. The valves are finished and installed. The rocker arms are completed. That completes the heads.
This is the distributor for the Peewee. Made from clear acrilic rod it should be cool to see the smorks jumping all over the place in there.
This is the camshaft that was created by following the steps in the article. Click Here to go to the article. That being said, I used the "hot" table that can be found at the Bob Shores engine Yahoo group. The cam was made with extra duration and a smidge extra lift. The distributor gear is bored to fit and pressed on the shaft. Then the outer diameter of the gear is turned to size and the rear bearing is pressed on. The timing gear and front bearing are reamed to a slip fit. The timing gear was modified to fit behind the front cover by reducing the thickness of the hub and redrilling for the set screw. The gears came together very nice with no noticeable slop.
The water pumpis also complete. I changed the pump so it discharges from the rear and milled a pocket in the front for an o-ring incase the shaft leaks. I also changed the pulley to a modern performance pulley. None of the performance outlets had one in stock so i was forced to make my own.
Sense the last installment there is the addition of black paint. I also made the rods and rings. I used bob shores method on this set. If they fail i will try the method using the fixture. The rods are like little H-beam rods. The wrist pin will press into the rod and float the piston. The Intake manifold is also complete.
Here is an update on the build. The carb is completed as is the radiator. I deviated from the bob shores method. I did'nt want to make the punch and squish the tubing for the core so i designed my own method. I made a fixture to drill the holes and another to space the fins for soldering. The tanks were made from solid and the fittings and things were soldered into the tanks. The tanks were then soldered onto the core. All worked well and I am happy with my first attempt at a radiator.
Things are moving along. The plumbing is almost finished. The radiator and fuel tank are complete and mounted. I am working on a tubing bender for the exhaust system. The entire project has been relocated to a permanent slab of corian. I'm getting close!!
Time to take the Peewee out of the work in progress. The little bugger is done. I think it is running well and couldn't be more pleased. All that has to be done is clean and polish and paint the pipes flat black.
I was in the garage trying to get the thing to fire. It would run on 2 cylinders only. When I cranked it by hand the Peewee would fire in the center of the rotor. I took the copper plate off the rotor and moved it back about 22.5 degrees and told my wife "grab the camera, I think it's going to start". This is the video she took.
First run video: http://www.youtube.com/watch?v=P5WEAdKPG1M
This video was taken after some tuning of the carb was done and thing were running well.
Final video: http://www.youtube.com/watch?v=1-JRQGPswVA
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