Motor Orientation

[Sean Maisey]

A couple of cars I have recently looked at have me thinking "out of the box" on the whole conversion process...

What if I took a very different approach to converting the car and turned the motor sideways?

Fabricate a LD200 sized box to hold a conventional LSD like a Franklin racing unit. Attach via a short drive shaft.

This is how the Legends cars and Diaso do it.

The beauty of the solution is that it would allow a completely stock rear end of the car, and in a later Tattus or VanDiemen would make the conversion process much easier.

Am I missing something. Would the intake and exhause be workable around the engine bay frames? Drive loss of chain drive vs. direct?

This idea has me intrigued...

Sean

[Rick Eskola]

Sean I had thought about that very samething.
My thought was to modify a Winters Quick change rearend the mini version used
by Diasio and the Baby Grand stockcars.
I would remove the axel housings and machine pieces to except CV joints and add
halfshafts.
Turn the engine sideways, and run a short driveshaft to the yoke of the Quickchange.
This might get kinda pricey, but so are chains and sprocket replacment.
Gearchanges would be easy. Don't know how much this unit would weigh or what kind
of power loss. "Just thinking"

Rick

[R. Pare]

It can be done - I don't see any reason why not at least as yet.

The problem with the available IRS units is size and weight - they are huge compared to what is actually needed - most of the centersections available weight about 60 lbs, whereas a bespoke unit for this application can probably be done well under 20 lbs for about the same price.

The biggest problem is deciding on whether to put the drop gear ahead of the diff or behind it ( behind is easier), and whether or not there are the drop ratios availabe that we need.

[Sean Maisey]

Looks like the Dwarf car guys have more or less standardized on the Toyota "8 Bolt". Small, light(?), cheap and lots of ratios available... Looks like a good candidate.

[R. Pare]

I'm not sure that I'd go to a CWP like that and expect it to do the job. Unfortunately, we may need more ratios than what they have available, so a rear of this type really needs a drop gear. While not the cheapest stuff available, I'd probably stick with a CWP from the LD200 (since it is the de-facto "standard" at this time) and use a set of change gears as the drop gears.

Plus, changing drop gears is a ton faster and easier than changing a ring and pinion!

[Art Smith]

Richard-

what functionality is included in your estimates of 60lbs and 20lbs? are both stiff enough to be used as a stressed member of the frame in torsion? I'm looking at significant structural loads from the pushrod pivots and A-arms in back given a wing and/or a diffuser with the large tires.......................... if the "third member" case isn't up to the job that means more weight from 4130 to provide the structural stiffness in torsion. the larger the fifth spring rate can be made the lower the car can be set-up opening other more interesting doors.

if you listen to the pundits (not recommending you do that), there should be a buyer's market for used LD-200's and their change gears for the foreseeable future........ stock (aluminum with NO lightening) Hewland LD-200 case, side cover, bearing carrier, rear cover, and steel studs weigh 24.1 lbs as measured on my shop electronic balance (picture enclosed). readily available ring & pinions and change gears solve most of the hard problems significantly reducing the potential project risk at the cost of weight. while not necessarily an elegant solution, it's weight reduction strategy is extremely straight forward and lends itself to an incremental implementation.


Art
artesmith@earthlink.net

[R. Pare]

If the mounting system is that the case is to serve as as part of the chassis structure, then the weight would go up a bit for sure. I was trying to compare using like mounting systems - using a Winters or Speedway mini QC IRS rears (which weigh in the neighborhood of 60 lbs with a spool) will require a tube structure to mount it and the suspension, so my comparison was with this unit designed to mount the same way.

As an off-the-cuff guess, a unit designed much like the Stohr "spar" as a stressed member can possibly come in at around 30 pounds total, and probably less. Again, that is just a guesstimate as I haven't actually designed one as yet.

Remember when looking at the LD200 that there is a lot of material there that would be cut away if used in the manner I'm talking about. The pinion and layshaft can be shortened a lot if only one set of gears are needed, and with it all of the shift system weight, etc.

If I were to really get serious about this sort of project, I would make it as a two-piece mag casting, split at the diff bearings (like the mid 80's March 86T box), or even split top and bottom, with diff preload adjustment like for the Ford 9". The machining then gets really easy, and CWP setup can be done in less than 30 minutes.

Not a tough project at all, but would take more money and time than I am willing to invest right now! (I'm swamped right now anyway). If I could get an order for 10-15 of them, it would become feasable as something for next year.

[sidney]

I looked at this type of option as well, but I couldn't determine how to balance the weight of the motor right to left and still drive off of the Input shaft to the LD. I think the Dwarf cars have unequal axles. This idea interestes me, but I worry about balance left to right in the car.

Ian

[R. Pare]

While I have no idea what the lateral position of the tranny shaft would be in a longitudinaly oriented motor, most likely if a bespoke spar design is done, the crosshaft can be moved sideways ( as well as the CWP) to minimise any misalignment. Also, most likely any particular setup will require u-joints to correct misalignment.

Balancing any left/right weight discrepancy can probably be accomplished just by careful placement of ballast, the batteries, oil tanks, etc.

[Sean Maisey]

The more I think about it the more I like this idea. If a "Stohr Spar" like replacement for the LD200 could be produced it would be a pretty neat package.

- Use one standard LD200 ratio to change final drive. Shorten (or spacer) gear stack accordingly.
- Use all LD200 hard points allowing use of stock suspension intact.
- Use the stock bellhousing casting
- fabricate engine mounts utilizing the stock Pinto upper and lower (pan) mounting points.
- Drive shaft parts readily available from the Dwarf car crowd.

With a little work this could make the conversion process VERY achievable for the masses. It literally could become a bolt in change for a lot of the chassis, and would definitely minimize the frame reengineering...

This approach could use a lot of off-the-shelf parts and really drive down costs and allow commonality of parts from Pinto/Zetec/F1000 configurations...

Very interesting...

Sean

[Art Smith]

This approach could use a lot of off-the-shelf parts and really drive down costs and allow commonality of parts from Pinto/Zetec/F1000 configurations...

use of an LD-200 case/derivative case versus other potential solutions has lower technical risk and lower schedule risk at the cost of weight. it will get someone running quickly but I doubt it's a low cost solution. getting the weight out will mean sooner or later nothing can be used straight from Hewland. Titanium &/or Magnesium, 5-axis milling, and custom turning operations are all expensive and will be required to get the solution down to competitive weight. it's my sense the LD-200 case is a "time-to-market solution" for those interested in market share............... the in-board pick-up points currently supported by the LD-200 are living on borrowed time; they're gone as soon as someone with a workstation completes their work relocating the pick-up points for the benefit of the wider tires, an optimized diffuser, and to incorporate a low-drag fairing for the half-shafts..............

Art
artesmith@earthlink.net

[Sean Maisey]

Art,

I do not disagree. I am primarily interested in getting some cars out on track and getting some force behind the F1000 concept.

There is little doubt that enterprising individuals will build purpose--built cars that are optimized to suit the rules. These cars will certainly outperform 1990s vintage conversions - eventually.

The problem that I see is that formula car participation is plummeting at an alarming rate in the SCCA. I want to do something NOW to present attractice alternatives... I see converted FC cars as a quick way to build support for the class. I do not think any reasonable person thinks they will be competing for a Runoffs win in a 1995 VanDiemen conversion some day down the road.

One of the chief objectives of F1000 is to create a neat high performance car with F1 like shifting, brakes, motor for a minimal amount of $$$.

I have competed at the Runoffs many times and in several different classes. I can not reasonably travel to Kansas, so I am more interested in making racing fun and affordable now. The thought of an open wheel version of my old Stohr DSR is exciting to me now. Running at better than FC times with 12,000 rpm howl and paddle sequential shifting, left foot braking, big brakes etc... gets my juices flowing.

Will somone wealthier jump in and spend Ferrari-like $$$ and go faster? Doubtless. I will still have a lot of fun pretending to be the Williams Cosworth team...

Your mileage may vary,
Sean

[bryancohnracing]

If you kept part of the shifting mechanism, you could use a single ratio for as your "drop gear" and keep reverse installed on an LD200. How's that for a bonus to a F1000 car?

As for the alignment question, just how far "out of alignment" could one run a shaft drive from a motor to gearbox?

Think of all the shaft drive bikes out there. The swing arm's have a fair range of motion, so surely a drive shaft could live with some kind of permanent angle of "attack".

Good thinking Sean!

bryan

[R. Pare]

Brian: I believe that most u-joints can operate up to about 30 degrees, depending on the design. Many CVs can operate higher. The problem then becomes just how short the distance is between the tranny shaft and the front of the LD, and how much power is lost thru the joints, containing the side and thrust loads, etc. You would need to make a new LD input shaft to allow it to attach to a joint, and be short enough to minimise the intermediate shaft angularity. This type of conversion on the surface sounds good, but it has it's own complexities.

However, a spar can be made that will bolt right in, possibly using the existing engine side framework. The question then becomes whether or not they will clear the engine and it's ancillaries, and chain to lower a-arm clearance.