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94eg!

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About 94eg!

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  1. Tooling? Most of the parts are machined. The molded suspension trees are few and shared with common mid-level performance chassis of the day.
  2. Even when I raced, I couldn't/wouldn't buy a new one. MSRP of $1k USD for a touring chassis? I bought my 415 MRE for $200 used with spares. TamiyaUSA had to blow out 201s for $199 for a really long time to move them. Only reason I purchased one. Personally I think the only reason they produced these kits was to chase down world titles, which creates brand recognition. There's no way they're making money on them. Of course a re-re would have zero development cost which is probably where all the $$ originally went.
  3. 94eg!

    HPI ?s

    HPI Super RS4 EP When I first built it in 2000, I ran a custom soldered 8-cell 3000mah nimh saddle pack, Speedworks 10-turn double and Novak Super Rooster. Needless to say the motor didn't last too long. One of segments of the commutator actually delaminated from the rotor and crashed into the motor can. I still have that rotor as a trophy.
  4. What front tires did you use? On a stock DS, I found the original kit setup was specifically designed for the rib-spike fronts and spire-spike rears. Once the front rib-spikes wore down to a regular tire, there was so much front grip, the rear had no hope of keeping up. Ran mostly on asphalt and sometimes had packed clay. Car ran terrible in loamy dirt due to excess front grip from tall ribs. At the time I didn't really know what I was doing. DS was my first slipper/ball-diff car, and I think I ran the diff too tight. It hadn't occurred to me to loosen it. Once I got into more advanced cars, I restored the DS and put it on display.
  5. They are made for specific racing classes during specific eras. The engineering takes into account all the cutting edge electronics of the day. As the electronics changed, the cars evolved in reaction. You can't get matched round cells anymore, so all the older chassis would need a ton of mods to run lipos. I know cause I ran a 415 MRE when lipo first took off. Filing expensive bulkheads was the only way to make even the smallest of lipos fit (3800mah). Not to mention how off balance left/right the entire car was (due to extreme battery weight difference).
  6. If there is excess Ackerman for a given vehicle path, it would act as added front toe-out. If there was a lack of Ackerman, it would behave as added toe-in. With so many other variables, one must test setup changes on-track to fully comprehend these effects in various scenarios (every turn on a given track). If on-track benefits are discovered for given conditions, then this data is added to the arsenal of "set-up" options. This was team TRF was for.
  7. The graph is comparing the angle difference between the inside and outside wheel at 3 different points. Essentially the stock Dyna Storm steering setup provides a huge amount of Ackerman.....which, in theory, provides much more accurate control in extremely tight turns (as Collin has confirmed).
  8. Blah, nevermind. Imediatlely found out that if the bell cranks aren't perfectly parallel, then it completely throws off the steering angle of the right bell crank. In fact, I would say getting the length of the drag link to perfectly match the center spacing of the bell cranks is of the utmost importance. I lengthened that rod +9% and it throws off the right bell-cranks by 1.5° in either direction (3° total).
  9. For some reason it just popped in my head that altering the length of the drag link between the 2 bell-cranks might also be an Ackerman tuning tool. I'll play around in cad and report back.
  10. That's amazing you did actual rapid prototype testing of custom steering components. I've always wanted to try making custom Ackerman c-hubs for the Avante series. I feel that chassis still has a bit of room for creative improvement (plus I'm a fanboy I guess).
  11. We'll a quick sketch in CAD revealed something very interesting. A Dyna Storm style steering system makes WAY more wheel angle difference than identical static geometry with a steering bridge in it's place. These are drawn with bell cranks at 0, 30 and 60 degrees. Cyan is Dyna Storm storm style and yellow is the steering bridge style. No actual measurements taken, so this is only for theory.
  12. BTW I believe real Ackerman is created by the angle between the steering knuckles axis of rotation and tie-rod pivot. The shimming of the steering bridge common in RC plays more of a secondary role of modifying the curve of the difference between the two wheels. I believe this why the Avante series will always have relatively awful wobbly steering. It effectively has no true Ackerman since these two pivot ponts are parallel with the centerline of the car.
  13. I'm certain Tamiya did that on purpose. From photos of the 1992 TRF211x it appears Tamiya developed this system for competitive racing. However.....when they finally returned to competitive 2WD with the TRF201, they had switched back to more common style steering bridge. I think they stuck with that through the TRF211XM. I'm not saying one is better than the other (I never raced 2wd off road). I'm just pointing out Tamiya abandoned the Dyna Storm system for whatever reason. Trying to piece together the history of engineering choices always fascinated me.
  14. Dyna Storm has a relatively impractical and outdated steering mechanism. The tie rod balls are attached to the bell cranks instead of a steering bridge like all modern cars. I remember distinctly that this causes a very sudden change of angle on the inside tire at full steering lock. Try removing the balls and drag-link and fitting a custom steering bridge cut from frp or carbon fiber. This will allow you to test various pivot point locations for the tie rods and see what fixes the problem.
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