Author Topic: 917 180 degree V 12  (Read 85042 times)

Offline steamer

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Re: 917 180 degree V 12
« Reply #150 on: July 21, 2016, 07:13:17 PM »
Been thinking about that Mike.  Is bet the photo I posted was to a turbo 917.     It would make perfect sense.

Dave, you could be right about it being from a 1,500 HP Turbo 917. That crankshaft could well be an aftermarket product used to rebuild an original engine to make it more bomb proof.

Who you going to trust?

Mike




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It's going to be a heavy crank.   Even if it wasn't it'd need a big flywheel, so I don't see an issue with a big heavy crank.

Dave
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Offline Admiral_dk

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Re: 917 180 degree V 12
« Reply #151 on: July 21, 2016, 10:47:10 PM »
Dave - are going to make it a two part crank with a Hirth-joint ?

If so - I would personally consider a three part crank, with the gear in the middle as the third part. It would admittedly require the double amount of Hirth-joints - but it would make the gear a lot easier and both cranks can probably be identical ....

Just an idea.

Offline steamer

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Re: 917 180 degree V 12
« Reply #152 on: July 22, 2016, 06:10:08 AM »
Maybe Admiral,   I just might make it 1 piece and cut the gear in place.

Dave
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Offline steamer

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Re: 917 180 degree V 12
« Reply #153 on: July 24, 2016, 01:55:57 PM »
Hey Mike,

What would you think of 4 carburetors, centered in the middle of a group of 3 intake stacks.   The stacks either side of which would be dummies and blocked off.   Then put a transfer port in where the slide throttle would go.....

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Vixen

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Re: 917 180 degree V 12
« Reply #154 on: July 24, 2016, 03:37:15 PM »
Dave,

Four carburetors, each feeding three cylinders, would be an elegant technical solution. Better technically, perhaps, than two carbs, disguised as turbos, feeding each bank of six cylinders. Although the dummy turbo route could be made to look more realistic. In the end it will be down the aesthetics, which solution looks best and most like a Porsche 917?

What sort of carburetor are you thinking of, and how difficult will it be to disguise them? I have found the rotating barrel (not butterfly) type of Walbro carburetor, to be very stable and reliable. Unfortunately the diaphragms do not like methanol being designed for gasoline. Keep the carburetor bore small if you want an easy handling engine, you are not trying to produce hundreds of horsepower.

Mike
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Offline gerritv

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Re: 917 180 degree V 12
« Reply #155 on: July 24, 2016, 03:43:47 PM »
While searching for something completely unrelated, I came across this interesting description of making camshafts.

Page 175  of Machinery Volume 28, 1922 (https://books.google.ca/books?id=jwU0AQAAMAAJ) has a complete schedule of operations. Seems worth creating a set of indexing plates to do the required machining.

Gerrit
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Offline steamer

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Re: 917 180 degree V 12
« Reply #156 on: July 24, 2016, 03:58:05 PM »
Hey Gerrit....I'll probably use cam calc when the time comes...

Though and index plate showing where the events are would be useful to avoid indexing errors..

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline steamer

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Re: 917 180 degree V 12
« Reply #157 on: July 24, 2016, 04:00:20 PM »
There may be an opportunity for the use of the air boxes......

http://www.porsche917.com.ar/ZTecmotor06.JPG

Though having the bare velocity stacks is more attractive to my eye...

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline steamer

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Re: 917 180 degree V 12
« Reply #158 on: July 24, 2016, 04:02:23 PM »
Dave,

Four carburetors, each feeding three cylinders, would be an elegant technical solution. Better technically, perhaps, than two carbs, disguised as turbos, feeding each bank of six cylinders. Although the dummy turbo route could be made to look more realistic. In the end it will be down the aesthetics, which solution looks best and most like a Porsche 917?

What sort of carburetor are you thinking of, and how difficult will it be to disguise them? I have found the rotating barrel (not butterfly) type of Walbro carburetor, to be very stable and reliable. Unfortunately the diaphragms do not like methanol being designed for gasoline. Keep the carburetor bore small if you want an easy handling engine, you are not trying to produce hundreds of horsepower.

Mike

I would probably run this engine on Gasoline anyway....Some Cam 2 perhaps....for the right "smell"....Nothing like the smell of 120 octane in the morning....though at about $10/gallon.....
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Vixen

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Re: 917 180 degree V 12
« Reply #159 on: July 24, 2016, 04:25:17 PM »
Quote
....for the right "smell"....Nothing like the smell of 120 octane in the morning....though at about $10/gallon.....

Well there is perhaps that smell of marzipan (almonds) from a Mercedes Silver Arrows burning a cocktail of Nitro Benzine, Acetone, Ether and a little Methanol at 2 miles per gallon. It makes your eyes water and your heart beat faster.

Mike
« Last Edit: July 24, 2016, 08:28:25 PM by Vixen »
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Offline b.lindsey

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Re: 917 180 degree V 12
« Reply #160 on: July 24, 2016, 04:38:32 PM »
Quote from: steamer
[/quote

I would probably run this engine on Gasoline anyway....Some Cam 2 perhaps....for the right "smell"....Nothing like the smell of 120 octane in the morning....though at about $10/gallon.....

About the same as Coleman fuel Dave. You get this project done and I am doubting the fuel cost will be of much concern.  ;D

Bill

Offline steamer

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Re: 917 180 degree V 12
« Reply #161 on: July 24, 2016, 04:42:11 PM »
Quote from: steamer
[/quote

I would probably run this engine on Gasoline anyway....Some Cam 2 perhaps....for the right "smell"....Nothing like the smell of 120 octane in the morning....though at about $10/gallon.....

About the same as Coleman fuel Dave. You get this project done and I am doubting the fuel cost will be of much concern.  ;D

Bill

Yeah....but Cam2 just has that smell!.....Bubba knows what Im talking about....
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline steamer

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Re: 917 180 degree V 12
« Reply #162 on: July 24, 2016, 07:47:12 PM »
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline stevehuckss396

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Re: 917 180 degree V 12
« Reply #163 on: July 24, 2016, 08:09:37 PM »
Quote from: steamer
[/quote

I would probably run this engine on Gasoline anyway....Some Cam 2 perhaps....for the right "smell"....Nothing like the smell of 120 octane in the morning....though at about $10/gallon.....

About the same as Coleman fuel Dave. You get this project done and I am doubting the fuel cost will be of much concern.  ;D

Bill

Yeah....but Cam2 just has that smell!.....Bubba knows what Im talking about....


Yes I do!!

Turbo Blue is only $7.00 a gallon. Cheaper than Coleman and smells way better!
Do not be like the cat who wanted a fish but was afraid to get his paws wet.

Offline steamer

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Re: 917 180 degree V 12
« Reply #164 on: July 24, 2016, 08:47:00 PM »
Quote from: steamer
[/quote

I would probably run this engine on Gasoline anyway....Some Cam 2 perhaps....for the right "smell"....Nothing like the smell of 120 octane in the morning....though at about $10/gallon.....

About the same as Coleman fuel Dave. You get this project done and I am doubting the fuel cost will be of much concern.  ;D

Bill

Yeah....but Cam2 just has that smell!.....Bubba knows what Im talking about....


Yes I do!!

Turbo Blue is only $7.00 a gallon. Cheaper than Coleman and smells way better!

Awesome!!!!
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

 

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