Building a 917 engine help!!

[jgambino]

OK so there has been a lot of talk more than a few years back on combining two 911 engines together to somewhat recreate the flat 12 917 engine. my question is how does one achieve this? i don't understand how it could be connected to the transmission. does anyone have have any diagrams or detailed pictures or input on how to accomplish it? I've been brainstorming for years over this and finally decided to post in the forum.

[Flieger]

The 917 crankshaft has the same number of throws and position of throws as a 911 crank. Each throw was wider to fit two rods though. So I am really not sure why you would want to go through all the trouble to put two 911 engines together. I think you'd still have torsional vibration problems whether you took the drive from the center like a 917 or from the rear like a 911.

I'd just use one 911 engine. To put the two together you'd need to make an adapter to hook the flywheel end of one crank to the front end (fan end) of another. Or else convert one to turn in the opposite direction and then mate them flywheel to flywheel, then have a gear setup or chain setup to a layshaft going under the engines to a tiny clutch and a gearbox like the real 917.

[jgambino]

OK that makes sense. I'm originally asking because i have an original 917 chassis and body if it was a kit car id just skI'mp out on the engine and cut corners its just I'm going crazy trying to decide the best approach to go about what engine to put in the car without ruining it.

[HawgRyder]

If you are lucky enough to have the car...why not poll the people on the board to find an original engine?
After you find an engine...there are probably there are probably a thousand more special parts to find as well.
Pictures of what you have might help.
We would all like to see another 917 come to life.
Bob

[jgambino]

i thought all the engines where either in museums or in the remaining cars that are out there and to be honest didn't one auction off on-line a long time ago for like 1 million dollars or somewhere close unfortunately i don't have this kind of money i inherited the car from my father and i really want to get this thing running again and if it cant have its original than i can at least have it remain all Porsche at least with a flat six that is built which is still upsetting but this car no matter the engine situation needs to be brought back to life in some way shape or form and I'm just trying to figure out a path maybe for now just to get it up and running and can go the flat six route while i try to locate or fabricate a replica engine. but locating an original i have no clue how to go about that at all.

[Flieger]

Wow, I had no idea. I just assumed you were making a replica. But yeah, you won't be able to afford a real type 912 engine unfortunately (I wouldn't either). So I would say just use the 911 and enjoy it while you look into getting a real 917 engine.

Is the frame structurally sound? I'd be worried about fatigue cracks with a welded aluminum tube frame that old, unless it doesn't have any races on it.

Take a look at what these guys do on their replicas: http://www.baileycars.co.za/index.php?option=com_content&view=article&id=53&Itemid=56

[jgambino]

wow thank you so much flieger thats a really good detailed description and yeah it has no races it was a spare body and chassis just in case something happened.

[HawgRyder]

Don't forget...you also need to check the frame for hydraulic integrity...the oil flows through some of it!
Bob

[MBEngineering]

HI jgambino

are these photos any good for you









drive is off the shaft at the bottom of the crankcase near the oil pump

regards mike

[Lapkritis]

You might consider contacting Porsche in a situation such as this. I would network there and be prepared for a long haul but they should be able to assist with determining authenticity and appropriate engine to match. What you may end up with in the end is you have a chassis and another guy has an engine... someone has to sell for the two to be united. If you're interested in historical preservation of these cars for future generations, it should be between parties to determine the best home. A private collection where it hides for another 50yrs may not be the best home the same as an engine that isn't correct. Opinions may vary but that's my $.02.

Best of luck.

[911pcars]

Originally Posted by jgambino

OK so there has been a lot of talk more than a few years back on combining two 911 engines together to somewhat recreate the flat 12 917 engine. my question is how does one achieve this? i don't understand how it could be connected to the transmission. does anyone have have any diagrams or detailed pictures or input on how to accomplish it? I've been brainstorming for years over this and finally decided to post in the forum.

What's your budget or the skills to pull this off? Maybe you don't realize the design, engineering and fabrication work needed to do this right.

BTW, the 917 was a single engine. What you're trying to do is put 12 Porsche cylinders in the 917. Not the same thing, but I think you understand that. Suggest you study how a 917 is built first before starting that CAD file.

Here's one path to take:
Porsche 917 Engine for sale | Rally Cars for sale | rally & race car classifieds from Raced & Rallied

Sherwood

[HawgRyder]

If I were forced to use 12 cylinders in your situation...
I would think about stacking 2 911 engines end to end (both in the same orientation).
That means the flywheel of the front engine (remember..this is a mid engine car) would be connected to the front snout shaft of the rear engine with a coupler of some kind.
This could also afford you the opportunity to place a bevel gear system on the coupler to get a horizontal fan installed.
Some sheet metal to cover the gap...and a support for the fan unit...a BIG air shroud...and separate oiling systems.
Lots of work.
A long time back we did this with 2 VW engines to create an 8 cylinder race engine...mixed results...it was heavy...had vibration problems...and was a ***** to tune.
Bob

[Das Mike.]

Got a chassis number? Let's see photos of the car!

[Lapkritis]

http://hartford.craigslist.org/cto/4612708527.html

[dhrcr911s]

that engine picture needs to be added to this post. Good luck.

IMHO, sell the chassis and body and enjoy watching someone else with deep pockets make it come to life.