Visible V8 @ 7056 RPM. The little engine ran 7056 RPM today. And more important, stayed all together and still runs fine.
The existing oil was changed out with a different type of oil that has a lower friction. This made the difference needed to reach 7000 RPM +. This is 70.56 times faster than the original design speed. The pistons are moving up and down 117.6 times per second @ 7056 RPM.
This little engine is a real trooper and has been surprising to me that it can "take a licking and keep on ticking" just like a old Timex watch.
The stress on this engine is extreme at these speeds and my current tests show that in order to go any faster, more drive power is required. I figure a one HP electric motor will be needed to push this engine any faster. At this time, I am ok with just 7056 RPM and still all together in one piece. A one HP AC DC electric motor would be bigger in size than the Visible V8.
My goal was not so much to run at a high speed, but to solve a valve spring problem. The Valve springs would shatter above 5500 RPM. Then I would have to change out the valve springs. The new camshaft I made seems to have solved the problem. The current redline is now 6000 RPM.
A disassembly of the engine is now in order to check for wear or parts stress
Also please remember, this Visible V8 has been modified for high speeds and has more than one year of testing to run like you see here in the videos. A stock out of the box Visible V8 is not going to do what you see here. Well may be just one time. If you are going to put a motor on your Visible V8, I would keep it below 1500 RPM for long life. They will run a long time if you lubricate your engine before each run and keep it below 1500 RPM. Most people use a RC truck motor to run their Visible V8s. Several people have done this and put their Visible V8 on You Tube. If you contact them, they may be able to tell you how they did it. I have never done this, so I don't know how to do it.
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Notes from log book:
Visible V8 Test # 135. 2/3/11
Block # 3 Crankshaft # 7 Camshaft # 3
Valve lash.003
Oil, type # 4. oil pressure 10 psi, oil temp 101 deg.F
Drive motor: Dayton 1/2 HP AC DC 120 Volt electric motor
Highest speed recorded: 7056 RPM
Engine damage: none detected, still runs OK.
Valve springs: OK
Red line in this test: NA
Noise level before test: Normal
Noise level after test: Normal
Vibration before test: Normal
Vibration after test: Normal
Speed controller type # 2
Update 2/7/2011: The disassembly of the engine after test #135 shows very little wear to the moving parts. No broken valve springs to report. Nothing came loose and best of all, no stressed or broken parts. Everything was checked out and then reassembled. It is good to go again. This is crank shaft # 6, block # 3 but it still has 6 of the original rods and all eight original pistons from the very first test and they look like new. Lubrication is the key here for sure.
