Subaru Conversion, CSOB style... Options

[jsteele22]

I've been thinking about what it would take to do a Subaru install
into my 914, and making it as inexpensive (and as home-brew) as
possible. I have a friend who is a machinist with a lot of enthusiasm
for the project, and a nice shop. He's done a couple of adapter plates
before, so I'm confident in that part. What I'm more curious about is
the flywheel. My idea for this is to take the stock Subaru flywheel
and machine it down to a radius of 4-5-ish inches, and then bolt a
stock Porsche (okay, VW) flywheel to it. So the Subaru FW becomes
just an adapter hub. Then, the thickness of the adapter plate is
chosen to get the input shaft to reach the proper position in the
friction plate/pilot bearing.

What do all you hybrid gurus out there think of this ? Am I
overlooking anything glaringly obvious ? (I haven't seen the pieces
in person, just in Haynes & on EBay.) Sure, the assembly will have to
be balanced carefully, but I think we (he) can handle that. The
engine I'm looking at is an EJ25 (165-ish HP) or, more realistically,
an EJ22 (130-ish), so it won't be an axle-snapper like some of you SBC
folks are driving.


Another issue is the engine mount. I've seen pics of Scott's, and
another one (tube steel) that I think Friid had made up, but not the
ultra-secret Renegade design. One idea I had on this is to not use
the stock Suby engine mount points, but instead make the adapter plate
several inches wider than the bell housing. Then each side of the
adapter plate could have an "L" shaped bracket bolted (sideways) onto
it; the bottom of the L would bolt vertically onto the plate at two
points, and the back of the L would point (horizontally) forward to
hang from a cross bar, either in the conventional (lower) position, or
up high across the top of the engine bay. This would take essentially
all of the torque off of the mounting bar bolts, and would leave an
open path for the shift linkage. In practice, I'm sure there would
need to be a little cross-bracing to prevent side-to-side motion, and
also to keep the L from straightening. Again, oh learned ones, what are
your opinions on this setup ? I *think* that suspending an engine
from the adapter plate is essentially what all the Subaru airplane
folks do.


I'm really pretty excited about the idea of putting a Suby in my car.
And it would be even more cool if it turns out to be affordable.

Please let me know what you think....

[jsteele22]

QUOTE (Mueller @ Oct 7 2005, 04:01 PM)

how about something like this for the motor mount? the bar is bolted to the adapter plate..the little "wings" attach to the engine mounts under the suby motor, and the other end of the bar attaches to a bulk head mount.... the factory 6 uses a single bolt on bulkhead mounts and has been used for bigger/heavier six motors

Hey, that's a pretty interesting idea; there's a lot that I like about it. Much of the engine weight is supported farther forward (at the stock Suby mount points), and no risk of bent bolts like was feared with the sideways bar strategies (connecting to stock 914 mount points on the chassis.) The force on the engine adapter plate will be much smaller in magnitude, will point straight downwards, and have less vibration to contend with. This would swing my vote back towards an aluminum adapter plate (see previous entry in this thread). I think that the suby engine casing doesn't surround the flywheel 360 degrees, but is open at the bottom; so it would be possible to have a thin adapter plate and still have a meaty section at the bottom for bolting the bar into. Also, the bar doesn't interfere with the shift linkage, another plus. I think (we'll have to see) your idea could be used with a mid-engine radiator setup, which I really want to do.


The main thing I'm concerned about is just how well the bar will prevent up/down motion of the engine. The P6 engines you mentioned mount to the bulkhead over a very short span, whereas this is a pretty long reach. I'm not saying that there is a problem, only that my first hunch is that it looks kinda spongy. OTOH, the stock 914 mounting scheme struck me as very "airy" at first. (I also thought those guys at CERN were blowing a little too much hot air when they called their cute little idea the "world wide web".(IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif) )

BTW, I think it is so cool that you can just jot down your ideas in a 3-d CAD system. I just use words or wave my hands around.