Ken Perkins Piet

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Richard Roller
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Ken Perkins Piet

Post by Richard Roller »

piet engine installed.jpg
I just wanted to let everyone know what's up with Ken Perkins Piet. I've reassembled the engine and have it sitting on the mount. I still plan on flying the Piet to Brodhead this summer. There are paperwork issues and I may have eye surgery soon, but that is the plan.
Steve D
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Re: Ken Perkins Piet

Post by Steve D »

As always looking good. If your eye surgery is a cataract lens replacement i had one done almost 20 years ago and it was easy. Just follow their directions.

Quick question. I have been conversing with a guy who may make some Ford Model A heads set up for dual spark plugs. Do you think there is a market for them?

Blue Skies
Steve D.
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

I wouldn't know if there would be enough demand for dual plug heads. Ken had talked, off and on, about doing that on his, but never did. I know he sold several drives for dual mags. I believe Ron Stoinoff has dual plugs on his Piet project.
JCB
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Re: Ken Perkins Piet

Post by JCB »

I bought my dual plug Lion aluminum head from Charlie Yapp...

http://www.secretsofspeed.com/lion-speed-head

Saves weight and adds ignition reliability.

John
Steve D
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Re: Ken Perkins Piet

Post by Steve D »

the secrets of speed site claims up to 120HP for a model A. Given that it is heavily modified is it a grenade?
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taildrags
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Re: Ken Perkins Piet

Post by taildrags »

Steve; if you just look at the A engine, which was about 200 cu.in., had a compression ratio of 4.11:1, and was rated 40HP at 2200 RPM in the original setup, see if you think you can get it to make *three times* its rated power output without cranking it up too much higher than its rated speed, which is pretty close to 'about right' for Piet speeds. Here's what one restorer with a hot-rodded engine said he did to get 100 HP out of his:

"The racing engine has insert bearings, a vintage Cragar OHV head (original from the late 1930’s —and not cracked!), counter-weighted crankshaft, lightened flywheel, V-8 clutch, full pressure oiling to the mains, Stromberg 97 downdraft carburetor with headers, and a 12V alternator system. Other than for the 12V system, the car is hopped up as one would in the late 1930’s."

Shaving the head, no doubt, would be one hot rodding tip. So, how high do you want to run the compression? With higher-octane fuel, the compression can be raised without detonating as readily, but you also raise the forces on the rods, piston pins, and crank. Can the stock parts take 3x what they were designed for?

Putting out more power means removing more heat, so the cooling system has to be beefed up. More water pump power draw? Larger radiator?

I dunno... each of the four cylinders, about 50cid apiece, would be responsible for putting out 30HP if the engine is to put out 120 HP as the website claims. That's 0.6 HP per cu.in. To put things in perspective, a stock O200 has about the same displacement and number of cylinders, it runs about 7:1 compression, and is rated at 0.5 HP per cu.in. It's pretty easy to get 120HP out of an O200 but I don't think anybody can say that the Ford A engine and the O200 are built anything alike as far as reliability.
Steve D
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Re: Ken Perkins Piet

Post by Steve D »

It appears you would not be stressing the engine much to crank it up to 70 HP or so! The model A's just sound so cool. Reminds me of the OX-5. The engine is turning so slow that it just doesn't look like it should be flying!
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

Ken's Piet ran this morning, the first time in 6 years. It started on the first pull with a hot mag. Minor oil leaks on the rear of the engine so far.
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

Hi everyone. It doesn't look like Ken's Piet is coming to Brodhead this year. The paperwork is still not straightened out and I can't see good enough yet. So I'll be driving, but I will be there.
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taildrags
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Re: Ken Perkins Piet

Post by taildrags »

Hi, Ken; not trying to be argumentative since I don't know exactly which paperwork issues are holding up renewed operation of the airplane, but if it was never de-registered, after a major change like what you've just performed on it, a logbook entry is made and the aircraft goes back into Phase I testing. It can be operated, but it's again subject to the more restrictive Phase 1 limitations such as the geographic area where it can be operated, a limitation to day VRF only, and no passengers can be carried. This continues until the test time is again flown off and the aircraft's papers are revised to reflect the new weight & balance including aircraft empty and gross weights, CG location, Vx, Vy, and Vso. This is all in 91.319(b) of the regs and in fact, you can just leaf back through the aircraft's logbook and you should find a logbook entry at the time the airplane originally entered Phase 1 flight testing and when that testing was completed and it entered Phase II. A logbook entry is made when Phase 1 testing is completed and the aircraft is returned to Phase II.

Now, if the registration was not renewed and has to be re-activated, the paperwork has to be filed and the fee paid.
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taildrags
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Re: Ken Perkins Piet

Post by taildrags »

Er... whoops... I should have addressed that to Richard, not to Ken ;o)
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

Oscar.
The engine work is not an issue. It’s the engine that came out of the Piet. No change in the installation or the airframe. The issue is that sometime in the last few years as the Piet set on the ground the airworthiness certificate and operations limitations have disappeared. They were kept in a zip lock bag along with the weight and balance under the pilots seat cushion. I’ve searched everywhere I can think of, at Ken’s old house and the hanger, but no paperwork. Unfortunately, Ken is no long available to ask. The weight and balance I can redo, I did them originally. I recently acquired a certified, under seal, copy of the original airworthiness and limitations from Oklahoma City. I plan on taking them to the local FSDO as soon as I can and see if I can get them to act. They haven’t been much help so far.
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taildrags
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Re: Ken Perkins Piet

Post by taildrags »

Richard; if you have any idea when (more or less) the airplane was first signed off, we can dig up the Phase 1 flight test rules that were in effect at the time. They have changed over the years, and if I recall correctly, there are some distinct benefits to having your operating limitations based under the older wording rather than the more recent wording. The FAA registry shows the registration being dated 7/1/1999 which would definitely place it under the older flight test rules if it was signed off for flight testing anywhere in that general timeframe. Are there no logbooks available to show when first flights were made?

And does it still have the "pair of dice instrument" in the front cockpit?
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

Hey everyone. I finally have the paperwork straightened out on Ken Perkin's Piet. It's amazing how fast something can get done when you get hold of a FAA Fed that is interested in helping you. I will be finishing the condition inspection soon. Then I'll get it back in the air. Can't wait!
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

Oscar. I apologize for not answering your question about Ken's Piet front cockpit instruments. I missed it entirely. Yes, it does still have the two dice instrument that say "Flying is a gamble". It also still has the "navibird" installed. I did take out the toilet paper roll moving map, it was always in the way when trying to get someone into the front cockpit.
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

Great day everyone! Ken’s Piet, N34KP, has flown again! This morning I flew it across town from KIXD to K34, in Gardner, Ks. It ran like a fine watch, smooth. When I put the engine back together I tried a few different techniques, trying to dry up the oil leaks. So far, so good. The first time I’ve flown this a/c without an oil slick on the belly when I landed. K34 will be a good home for this Piet with no brakes. Two grass runways. I’m looking forward to some good flying weather and some good flights. See you all in Brodhead in 2019!
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taildrags
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Re: Ken Perkins Piet

Post by taildrags »

Richard; that's great news! Always nice to see classic airplanes like this one get air under their wings again!
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Richard Roller
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Re: Ken Perkins Piet

Post by Richard Roller »

Yes, Oscar, is is good to see the old bird fly again. I took it up again today to get back in the groove. A bouncy landing yesterday. Much better today. Piets are so much fun to fly.
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