Yet another Customised Optima Mid Custom Special

[Coelacanth]

I like the way the LWB mids look like a real competition buggy. The short mids just dont look quite as serious. I like the way the lwb handles too.

To me the swb looks better, but one cannot argue with the handling advantage the lwb gives. There is a reason after all why all modern buggies have lwb. I have personally seen how my lwb mid soaks up the rough stuff , i cant imagine the swb would do better .

How much of that can be attributed as much to the increase in tire diameter from 2" to 2.2" as a 10% increase in wheelbase? Not to mention the trend in track design these days having 1:10 cars make ridiculously long & high jumps that are way out-of-proportion to what 1:1 offroad buggies do....hence the need for longer wheelbases and bigger wheels & tires. It's all relative, IMHO.

Just playing devil's advocate here, but I wonder how well today's cars would perform on the tracks from 25 - 30 years ago? Maybe the longer wheelbases & bigger tires might suffer on the smaller, slower-speed, less flight-worthy tracks from BITD.

[EvolutionRevolution]

I like the way the LWB mids look like a real competition buggy. The short mids just dont look quite as serious. I like the way the lwb handles too.

To me the swb looks better, but one cannot argue with the handling advantage the lwb gives. There is a reason after all why all modern buggies have lwb. I have personally seen how my lwb mid soaks up the rough stuff , i cant imagine the swb would do better .

How much of that can be attributed as much to the increase in tire diameter from 2" to 2.2" as a 10% increase in wheelbase?

Increasing the diameter of a wheel does not increase the wheelbase (which is measured from axle center to axle center)

[rccars4sal]

I just recently visited a track under construction, and yeah,, the jumps are soooo big,, no way I will submit any vintage car to that. Its like when we were kids and jumping the poor rc off a cliff into the dry pond,, or over the trampoline or a pic nic table. My slash handled it well, but im sure 25 yr old car would break.

[Coelacanth]

To me the swb looks better, but one cannot argue with the handling advantage the lwb gives. There is a reason after all why all modern buggies have lwb. I have personally seen how my lwb mid soaks up the rough stuff , i cant imagine the swb would do better .

How much of that can be attributed as much to the increase in tire diameter from 2" to 2.2" as a 10% increase in wheelbase?

Increasing the diameter of a wheel does not increase the wheelbase (which is measured from axle center to axle center)

No kidding; a LWB chassis does, however. Re-read the embedded quotes. I know what wheelbase is.

[Coelacanth]

I should clarify what I meant:

Even though 2 cars may both be considered 1:10 scale, if one has a 220mm wheelbase vs. 200mm, 2.2" wheels vs. 2", runs faster & more powerful electrics on a bigger track, is that bigger car truly "better"? Or is it just a functionally bigger car that should obviously perform better on a bigger track? Conversely, on a smaller, tighter, twistier track with proportionately smaller jumps, wouldn't the proportionately smaller car outperform the "more modern" larger one?

I'm not sure what the ROAR specs were for cars in the 80's, but the Optima (for example) had about a 260mm wheelbase, give or take 5mm. The ROAR specs for 2005 (had to Google it) suggested a max. wheelbase of 292mm, more or less 12% longer. So, going with 2.2" wheels & tires instead of 2" makes perfect sense. Modern buggies are simply bigger than back in the day, and probably evolved that way to better handle the faster speeds & bigger tracks of today. But is it the longer wheelbase that makes them "perform better"? Or the bigger tires?

Or just the simple fact that the cars are outright bigger, and merely scaled up proportionally to suit modern track sizes & electronics?

I would bet that, all else being equal, a SWB car with smaller tires would outperform a slightly larger LWB car on the smaller, tighter, less jump-crazy tracks of yesteryear. It's all relative.

[hondaman]

I agree with your thoughts about the smaller car being at an advantage on the smaller track.. the larger car would be at a disadvantage in ease of drivability inthose conditions and likewise the opposite would be true.. at the 1:1 scale this is most definately true.. I have been to autocrosses where a smaller lower powered honda civic is faster through the course than a larger more powerful corvette.. buto. A larger track like a willow springs,the little civic is at a huge disadvantage..

IMHO..As far as the wheelbase issue, this helps with straightline stability versus a short wheelbase car.. the smaller tighter track would favor the short wheelbase while the larger tracks with more sweeping turns would favor the long wheelbased cars.. newer tracks favor the larger buggy/truggy well because the tracks are larger to accomodate the speed/power of modern electronics.. 2.2 wheels would help over all top speed while the 2.0 wheels would help accelleration.. gearing and power would make the gap smaller but at just wheel versus wheel this applies.. the wider cars help with lateral grip thereby hindering turn in speeds.. this is based on all things being equal (electronics, set up, and driver skill)..

Shawn

[Coelacanth]

I see wheelbase & track width as sliding scales. All else being equal, the longer the wheelbase, the better straight-line stability, as you said. The same goes for narrower track width. Shorter wheelbase & wider track favors tighter turning/better cornering. A LWB Optima Mid isn't the be-all, and isn't the best for ALL driving conditions. Neither is a SWB Mid. Choose what's best-suited to your driving habits on your favorite track.

Understeer a problem? Shorten the wheelbase or widen the track width (or a combination of both). Steering too twitchy and oversteer a problem? lengthen the wheelbase and/or narrow the track. That's a bit simplified to show the basic concept, but of course suspension, shock positioning, weight distribution, downforce of airflow, etc. all play a part...but as I said, all else being equal.

[hondaman]

I see wheelbase & track width as sliding scales. All else being equal, the longer the wheelbase, the better straight-line stability, as you said. The same goes for narrower track width. Shorter wheelbase & wider track favors tighter turning/better cornering. A LWB Optima Mid isn't the be-all, and isn't the best for ALL driving conditions. Neither is a SWB Mid. Choose what's best-suited to your driving habits on your favorite track.

Understeer a problem? Shorten the wheelbase or widen the track width (or a combination of both). Steering too twitchy and oversteer a problem? lengthen the wheelbase and/or narrow the track. That's a bit simplified to show the basic concept, but of course suspension, shock positioning, weight distribution, downforce of airflow, etc. all play a part...but as I said, all else being equal.

I totally agree.. it is a sliding scale.. it also changes with which drive wheels are moving the car.. fwd, rwd, awd.. while one way may work with one, the others suffer.. too many variables.. makes me dizzy just thinking about it too much..

Shawn

[alcyon]

Just tested my car on road today and i hear some clicking noises as if the belt is skipping. Upon returning home i inspected the car closely. I placed one hand behind the rear shock tower and the other in front and proceed to tug and the push the ends. Sure enough..there was movement and the culprit was the rear upper deck mount. It was sliding inside the motor mount and the msc brace. The threads were stripped and all my spare mounts exhibited the same tendencies. This will definitely cause the belt to skip. Tommorow i will ask my machinist to make a new deck mount out of aluminum 6061.

[HKS_TRD]

Very keen to see how the aluminum mount looks, will you have more than one made?

[alcyon]

Very keen to see how the aluminum mount looks, will you have more than one made?

For now, I only asked for one, I can make more if there is demand. I think everyone who runs their mid hard need an alloy upper mount as the threads in the plastic seem to be very weak and strip quickly.

[alcyon]

Very keen to see how the aluminum mount looks, will you have more than one made?

You asked ?

[HKS_TRD]

That turned out amazing
And now my next question, how can I get my hands on one of these?

[alcyon]

That turned out amazing
And now my next question, how can I get my hands on one of these?

Wow that was quick. I could make them, but making one was pretty expensive, in the territory of U$50. If I could get 10 guys who wants this I could bring down to $40 shipped.
You want one ? This is just in time to allow me to play around with my mid this Saturday !

[HKS_TRD]

Yeah I want atleast one. That's better than the vintage ones I have as its a direct copy of the original unlike the ones I have. I will be getting it anodised gold and putting it on the Turbo Mid SE-X. If the 21st Century Mid wasn't done I'd put it on that. I wonder if a Lazer bulkhead and upper deck could be made to fit a mid. Do you think it would be possible to have the A&L motor plate copied?