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Inline Slant 12
https://slantsix.org/forum/viewtopic.php?t=62888		 Page 2 of 3
Author:  GTS225 [ Thu Oct 04, 2018 4:29 pm ]
Post subject:  Re: Inline Slant 12
Personally, I'd recommend a fluid coupler.
https://www.youtube.com/watch?v=xfaMBGMpH1o

Basically, it's a stand-alone torque converter, and is independent of any hydraulic pump. The reason I suggest this is, if by chance something should happen to either engine while running, then it won't attempt to destroy both at once, and will give you a short period of time to shut it all down.

Roger
Author:  THOR [ Wed Oct 10, 2018 12:14 pm ]
Post subject:  Re: Inline Slant 12
I thought about a fluid coupling as well.

I wonder what the normal stall speeds are (if they have a stall speed)?

~THOR~
Author:  GTS225 [ Wed Oct 10, 2018 3:43 pm ]
Post subject:  Re: Inline Slant 12
The couplers I've dealt with were used to hook an electric motor to a large wood grinder, and the instructions indicated one could "regulate" the stall speed by how much oil was put into the coupler.
I suppose one could also affect the stall with different viscosities of oil, but you would have to consult with the mfgr.

Roger
Author:  emsvitil [ Wed Oct 10, 2018 11:38 pm ]
Post subject:  Re: Inline Slant 12
I don't like the fluid coupler idea.

Due to slippage, the 2 engines will run at different speeds.
Author:  lgu32 [ Thu Oct 11, 2018 12:12 am ]
Post subject:  Re: Inline Slant 12
2 slants parallel with their own 904's behind. Customized rear axle with 2 center sections each spinning of its own wheel. No connection between the 2 systems. "Center shaft missing" and spool for each rear end gear.
Author:  GTS225 [ Thu Oct 11, 2018 3:36 am ]
Post subject:  Re: Inline Slant 12
I'm thinking a '31 Chrysler isn't going to be wide enough to easily accommodate two punkins, side-by-side. You'd also have the problem of possible different engine speeds effecting the rear wheel speed(s).
Besides, he wanted them inline.

Roger
Author:  SpaceFrank [ Thu Oct 11, 2018 8:29 am ]
Post subject:  Re: Inline Slant 12
If you don't want to modify the front of the rear engine's crank, you could fabricate a press-fit coupler with a slightly smaller bore to give you more of an interference fit. When I was in the turbomachinery repair business, we often ran calculations for torque carrying capacity of interference fits to find out how much interference was required for a given application. Of course I'd have to dig out the machinery handbook to remember how to do it now.

More interference means you'll have to get the coupler even hotter or use a bigger press to get it on the front crank. That might get complicated considering the front seal design on the Slant.

As far as connecting the front engine, would a flex plate give you enough wiggle room for potential misalignment? If so it's just a matter of drilling the bolt pattern to give you the 60° offset you want.
Author:  THOR [ Thu Oct 11, 2018 10:11 am ]
Post subject:  Re: Inline Slant 12
As far as the flex plate goes, I would imagine it would work just fine since both engines will be on adjustable mounts; I can very finely tune the alignment in the cradle.

I was beginning to think about perhaps using an interference fit on the end of the snout, but machined at a slight taper. This would obviously still require some heating, and 2 more key-ways (for stoutness), but might prevent melting the front main.

The other thought I had was to cut the end of the crank and key it there, instead of cutting 2 additional smaller key ways into the crank where the balancer resides and using the small keys. The crank and adapter would be cut for a slight interference fit, and use the stock crank bolt to retain it.

Lots and lots of ideas!

~THOR~

On the other note, the '31 Chrysler really isn't much larger than a Model A Ford... no way are 2 powertrains going in there without extensive modification... my plan is to leave the rest of the car (Cowl to rear bumper) basically unmolested.
Author:  jcc [ Thu Oct 11, 2018 10:52 am ]
Post subject:  Re: Inline Slant 12
Quote:
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~
All my engineering training always taught me I had to define a problem first before beginning the solution phase.

What exactly are we trying to solve here?

But based on what I have read so far, I see huge torsional harmonic inline crank problems , that are beyond the scope of solving by most here.

Note, there is definite reason an OEM/aftermarket style damper is on the opposite end from the FW, and why it must a very tight/pressed fit with zero movement possible.
Author:  THOR [ Fri Oct 12, 2018 10:00 am ]
Post subject:  Re: Inline Slant 12
Quote:

All my engineering training always taught me I had to define a problem first before beginning the solution phase.

What exactly are we trying to solve here?

But based on what I have read so far, I see huge torsional harmonic inline crank problems , that are beyond the scope of solving by most here.

Note, there is definite reason an OEM/aftermarket style damper is on the opposite end from the FW, and why it must a very tight/pressed fit with zero movement possible.
I'll be the first to admit I don't have any proper engineering training.

The problem I'm trying to solve is how to couple 2 slant sixes in-line, for a straight 12 configuration. It doesn't need to last for 100,000 miles, and it doesn't need to make a ton of power; I just haven't seen it done before. Given that this forum hosts the most knowledgeable folks I've ever found regarding a slant, it seems the most reasonable place to ask the questions.

~THOR~
Author:  Old6rodder [ Fri Oct 12, 2018 12:42 pm ]
Post subject:  Re: Inline Slant 12
Sounds like a fun cobble.

I'd likely try a dual roller chain & sprockets set-up or a rubber padded dog style connector. Both available industrially, each allowing an amount of angular misalignment that should fall inside home cobbling limitations. Of course each would need adapting to existing components. Crank flange (and/or flywheel or flex plate) to one side, crank snout to the other.

That given, many are the diggers that managed it in the past with far higher HP mills than slants. There should be some record of some of'em.

I'd lean toward the dog style for its pulse cushioning and slide together feature, and time'em together for the same reason.

One dog part could be welded to the flange end of the forward mill fairly readily. The other to a crank dampener core, then Jesus bolted to the crank. A hardened key'd give you the best you'd get with this set-up. Likely not good for anything more than stock HP mills.

As I said, sounds like a fun cobble. 8)
Author:  jcc [ Fri Oct 12, 2018 6:33 pm ]
Post subject:  Re: Inline Slant 12
Quote:
Quote:

All my engineering training always taught me I had to define a problem first before beginning the solution phase.

What exactly are we trying to solve here?

But based on what I have read so far, I see huge torsional harmonic inline crank problems , that are beyond the scope of solving by most here.

Note, there is definite reason an OEM/aftermarket style damper is on the opposite end from the FW, and why it must a very tight/pressed fit with zero movement possible.
I'll be the first to admit I don't have any proper engineering training.

The problem I'm trying to solve is how to couple 2 slant sixes in-line, for a straight 12 configuration. It doesn't need to last for 100,000 miles, and it doesn't need to make a ton of power; I just haven't seen it done before. Given that this forum hosts the most knowledgeable folks I've ever found regarding a slant, it seems the most reasonable place to ask the questions.

~THOR~
OK, then to know when you have properly achieved your goal, it needs to be two slant sixes , preferably in line, that is unique, runs, is a solution able to "bragged" about ( my words) :D, longevity is not crucial, ton of power is not important. I assume last goal would be slightly less then twice a standard /6 output, to minimize coupling issues, etc. I would have liked to hear what the budget target is, to allow for unintended consequences in the build.

Fine tune the above for your own goals, and good luck.
Author:  Old6rodder [ Fri Oct 12, 2018 8:39 pm ]
Post subject:  Re: Inline Slant 12
Here's a link to an old thread on the HAMB looking into the cobble. Tends to wander, as is typical there, but some decent info and a few still working links.
Author:  THOR [ Mon Oct 15, 2018 11:05 am ]
Post subject:  Re: Inline Slant 12
Quote:
Quote:
Quote:

All my engineering training always taught me I had to define a problem first before beginning the solution phase.

What exactly are we trying to solve here?

But based on what I have read so far, I see huge torsional harmonic inline crank problems , that are beyond the scope of solving by most here.

Note, there is definite reason an OEM/aftermarket style damper is on the opposite end from the FW, and why it must a very tight/pressed fit with zero movement possible.
I'll be the first to admit I don't have any proper engineering training.

The problem I'm trying to solve is how to couple 2 slant sixes in-line, for a straight 12 configuration. It doesn't need to last for 100,000 miles, and it doesn't need to make a ton of power; I just haven't seen it done before. Given that this forum hosts the most knowledgeable folks I've ever found regarding a slant, it seems the most reasonable place to ask the questions.

~THOR~
OK, then to know when you have properly achieved your goal, it needs to be two slant sixes , preferably in line, that is unique, runs, is a solution able to "bragged" about ( my words) :D, longevity is not crucial, ton of power is not important. I assume last goal would be slightly less then twice a standard /6 output, to minimize coupling issues, etc. I would have liked to hear what the budget target is, to allow for unintended consequences in the build.

Fine tune the above for your own goals, and good luck.
It will certainly be unique. Lol

While I am not planning to dump a ton of money into the project, I do expect a few thousand dollars will be spent in engineering a couple and cradle that will function as intended. I do have a number of excellent fabricators in my car club, and I expect that when we actually start welding, we will run into a number of issues.

The glory here is that there is no time restraint.

I'm leaning towards trying the double roller chain and sprocket, and the rubber insulator approach. I'll likely create both for testing and see which is more likely to deliver what I am looking for.

~THOR~
Author:  Old6rodder [ Mon Oct 15, 2018 12:00 pm ]
Post subject:  Re: Inline Slant 12
Possible to add a sprocket to front of existing dampener on aft mill? Strength issue?
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