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Inline Slant 12
https://slantsix.org/forum/viewtopic.php?t=62888		 Page 1 of 3
Author:  THOR [ Tue Oct 02, 2018 1:27 pm ]
Post subject:  Inline Slant 12
Are ya gonna call me crazy? Probably.

I am looking at purchasing a 1931 Chrysler 4 door from a good friend for a "good" price :twisted:

Since the frame on it is super simple, I've been building a twin engine setup in my head...backed by a 727 auto and 8.75".

I did some searching and found a thread from 2003 regarding running 2 engines in 1 car, but it never really got anywhere. I am thinking of a 60 degree offset, so I wind up with cylinder firing every 60 degrees. They would each run their own ignition system and intake manifold but the exhausts would be tied together after collectors for scavenging.

I don't need much assistance in the way of fitting it all to the car; that part should be fairly straightforward after the frame fab work is done, but I definitely need assistance in coming up with a plan for a coupling to go between them. I'd like them on the same plane, crank to crank. Maybe a machined shank of billet with a 6 bolt flange on one end and a keyed shaft on the other? Break out your crayons and napkins!

~THOR~
Author:  coconuteater64 [ Tue Oct 02, 2018 1:38 pm ]
Post subject:  Re: Inline Slant 12
I am really intrigued by this! Maybe you could look at these couplers and find something. https://www.baldor.com/brands/baldor-dodge
Author:  THOR [ Tue Oct 02, 2018 1:55 pm ]
Post subject:  Re: Inline Slant 12
Thanks for the link!

A bolt together solution like the one I have attached would likely make the actual install much simpler!

The plan I have in mind is to build an engine cradle to hold both engines, and then use poly mounts to put in on the frame. Doing it this way I believe would be the easiest and most effective way to ensure that the engines are always completely centered to each other, unaffected by frame twist etc...

I would also be able to just unbolt the trans and peripherals, and pull the whole cradle from the car for any major engine work.

If I knew how to use CAD, I would draw it up there and post it up... haven't legitimately used any 3D modeling software in a looooong time. So paper and pencil it will likely be!

~THOR~

Attachments:
coupler.jpg
coupler.jpg [ 9.67 KiB | Viewed 8555 times ]
Author:  coconuteater64 [ Tue Oct 02, 2018 2:16 pm ]
Post subject:  Re: Inline Slant 12
I love it when a plan comes together! If Ma Mopar can mate five engines together to cram into a Sherman tank, anything is possible. I think the idea of keeping the engines together on a frame, and then mounting that frame to the car's chassis, would be the best way to keep the blocks from wanting to wiggle into different planes and snap the crankshafts. The only head scratcher is cooling.
Author:  THOR [ Tue Oct 02, 2018 2:46 pm ]
Post subject:  Re: Inline Slant 12
Cooling is definitely something that will become interesting quickly. I have a few ideas for it already, the key is how to package it.

~THOR~
Author:  emsvitil [ Tue Oct 02, 2018 5:20 pm ]
Post subject:  Re: Inline Slant 12
Is the front of an engine strong enough to attach to the rear of another ? ? ?

The rear has a flange and bolts, the front only a woodroof key. I'd think you'd shear off the key...…….

Connect them flywheel to flywheel in the middle, power takeoff there and then back to tranny.

Either one engine reverse rotation, or geared to get correct rotation.
Author:  coconuteater64 [ Tue Oct 02, 2018 5:34 pm ]
Post subject:  Re: Inline Slant 12
Tractor pullers do it all the time. Cut a second and third woodruff key slot in the front of the crankshaft.
Author:  emsvitil [ Tue Oct 02, 2018 5:55 pm ]
Post subject:  Re: Inline Slant 12
The woodruff key is only for alignment, it shouldn't have a load on it.


After I typed my first response, I remembered how the flywheel is attached to my mazda rotary engine.

It uses a 2 1/8" nut torqued to 300 some ftlbs on a tapered shaft. A tapered shaft can take the load.

The standard 3/4" bolt isn't strong enough. So machine the front as tapered, and then machine threads on the outside of the snout for a nut. Might need to install 3/4 bolt so snout doesn't collapse under compression.

I'd also think you'd want some give in the coupler as there's no way you can keep the engines from flexing a little on the frame.
Author:  emsvitil [ Wed Oct 03, 2018 3:19 am ]
Post subject:  Re: Inline Slant 12
https://petrolheadgarage.com/Posts/how- ... c-engines/

https://www.jalopyjournal.com/forum/thr ... ne.624584/

http://www.speedtalk.com/forum/viewtopic.php?t=18906
Author:  THOR [ Wed Oct 03, 2018 9:32 am ]
Post subject:  Re: Inline Slant 12
Hey Ed,

You bring up some excellent points. While I have a feeling that the engines being in their own separate carrier will reduce the chances of alignment issues due to deflection, obviously there will likely still be some, so some sort of isolator (rubber or poly?) installed in the coupler would likely be the best plan of attack.

Thanks for the article links too, I read through all of them and got some additional ideas on how to make this a reality.

My hope would be the development of a coupler which does not require modification of the engines themselves, if possible. Some trial and error will most likely be required on that front. I wonder how many other folks would be interested in a coupler if we could design one that actually works.

~THOR~
Author:  Dart270 [ Wed Oct 03, 2018 10:36 am ]
Post subject:  Re: Inline Slant 12
Funky and cool. I always dreamt about a V12 made from 2 Slants...

Lou
Author:  emsvitil [ Wed Oct 03, 2018 4:26 pm ]
Post subject:  Re: Inline Slant 12
For the rear engine you might get away with the normal front. (no taper modification)

But, you'd definitely would need the front crank bolt to clamp the adapter to the snout. (press fit isn't enough)

The friction due to the clamping should hopefully take the load. If the woodruff key doesn't deform, it's working.
Author:  emsvitil [ Wed Oct 03, 2018 4:28 pm ]
Post subject:  Re: Inline Slant 12
The adapter could be 2 CV joints (one which slides for length).

One CV joint on each engine with short axle between.
Author:  THOR [ Thu Oct 04, 2018 9:49 am ]
Post subject:  Re: Inline Slant 12
A CV axle is definitely a thought.

My hope is to try and keep the package as compact as possible, while allowing for easy(??) service on both engines concurrently. I think if done correctly, coming up with a keyed piece that the crank bolt would hold to the end of the snout might be the ticket.

At this juncture, we're not talking about massive power, just 2 stock 225s (I'd prefer 170s, but they are really hard to find) in a row, with single carbs, and single exhaust. Put it together and work all the bugs out before upping power and breaking things. :twisted:

~THOR~
Author:  slantzilla [ Thu Oct 04, 2018 10:46 am ]
Post subject:  Re: Inline Slant 12
Press the coupler on the rear engine and drill through for a bolt. Used geared adapters connected by a double row chain.

If you want a damper in between instead of chain, use a Lovejoy.

We use all kinds of couplers at work. One thing I can tell you is misalignment will kill them.
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