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TurnipJF

Random musings on performance ceilings, model selection and value

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The postal races have, amongst other things, given me cause for the first time to run a wide range of different cars under directly comparable conditions. The results have been surprising, and have caused me to wonder about a few things.

During today's attempts for example, I was going around with my Thundershot, and after a few runs managed a lap count that matched the one I set with my M-08 a couple of days ago on the same course under comparable temperature and humidity. It is a pretty decent lap count - I am not disappointed on that front. However the Thundershot in question is a restored original from '87, powered by a relatively humble GT Tuned motor, and apart from a wing and a 4-shock conversion utilising plastic CVAs, has no performance- or handling-oriented mods. Everything else I have done to it has been to enhance reliability. The 2019 M-08 on the other hand runs on a 13.5t brushless motor, and between the more advanced kit parts and the extra hop-ups I installed during the build, has loads of reasons why it should easily out-perform the heavier, older, less powerful offroad buggy, especially on a tight on-road course. So why doesn't it?

Part of this is no doubt a testament to the Thundershot design, which despite its age is still very good. However I am sure that most people would agree that the M-08 and Thundershot are in a different league, as evidenced by their design, materials and price brackets. What business does my Thundershot have keeping up with my M-08? Or to think about it another way, what business does my M-08 have being matched by a Thundershot? On tarmac??

Have I perhaps reached the point where my driving skill has reached a plateau in line with the performance available from a 1987 brushed Thundershot, and no matter how much I spend on fancier, more advanced models, I am unlikely to see any significant performance gains as a result? Not that this will stop me from adding more modern cars to my fleet anyway - there are many reasons apart from pure performance to buy a model - but has performance now ceased to be a factor?

Or could it be that the cars are not actually as different as they appear? There are pretty big design and engineering differences between a Grasshopper and a Thundershot for example, and these are reflected in my lap counts as I would expect them to be, but the differences between the Thundershot and M-08 are far less fundamental. One is RWD, the other 4WD, and the track and wheelbase measurements are noticeably different, but both have mid-rear mounted motors, independent suspension with coilover oil dampers, similar ratios between sprung and unsprung mass, etc. Perhaps, at my skill level, the differences aren't big enough to have much of an effect?

Or following on from the above, maybe it is something to do with the law of diminishing returns? A good car will give noticeably better performance than a basic one, but a great car will not have as much of an edge over a good one, and a fantastic car will have even less of an edge over a great one. Maybe since both the M-08 and Thundershot are above basic level, their differences don't translate into performance differences big enough to show in informal postal racing?

Or maybe it is nothing to do with the cars, but rather a question of tarmac and scale? A smooth piece of tarmac for a 1:1 scale car would be more like a cobbled street for a 1:10 scale car. Maybe the offroad buggy is simply better suited to tarmac, and the M-08 is only going to come into its own on carpet?

Or I could simply be over-thinking it. Maybe I just had a good day today, and a not-quite-as-good day when I drove the M-08? Maybe the cars are of significantly different performance levels after all, and my driving, while quite consistent from lap to lap, is nowhere near as consistent from day to day?

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To make you feel a little better @TurnipJF , F1 teams can spend millions only to achieve 0.5 second gain per lap..... :)

Your nearly stock Thundershot still beats my heavily modified one (and on paper quicker one?) so in that respect I think we can agree your driving is far superior to mine.

What I would like to see is how well you would do with mine.

I still think a buggy has a slight advantage over a touring car on tarmac simply down to wider track?  (250mm vs 190mm)

Also as you suggest, a good 4WD buggy chassis is indeed much closer in performance to a touring car then people imagine. The weight difference is minimal, in fact I believe my thundershot is lighter than your touring cars?

4WD, even the rather archaic version employed by the thundershot must still give a small advantage over a 2WD car, especially on cold rough concrete/tarmac. How does the thundershot compare with your 4WD cars?

I also believe you understate your 'humble' GT tuned - I believe it is a 500g torque motor? that will give significant advantage in a 4WD buggy as you can get the torque down to the ground without spinning tyres and that will give you better drive out of corners? 

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39 minutes ago, mud4fun said:

To make you feel a little better @TurnipJF , F1 teams can spend millions only to achieve 0.5 second gain per lap..... :)

True... ^_^

 

39 minutes ago, mud4fun said:

4WD, even the rather archaic version employed by the thundershot must still give a small advantage over a 2WD car, especially on cold rough concrete/tarmac. How does the thundershot compare with your 4WD cars?

At the moment, less than 0.3 seconds difference between their fastest laps, and 2 laps difference between their totals. That may change though - weather permitting, I'll be taking the TT-02 Type S out again tomorrow over lunch. I am sooo close to achieving a sub-7-second lap...

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26 minutes ago, mud4fun said:

4WD, even the rather archaic version employed by the thundershot must still give a small advantage over a 2WD car

 

Small it is not. Take the propshaft (or just the pins out of the front hex adaptors) out of the thundershot and see what a complete nightmare it is to drive quickly And accurately in 2WD...

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19 minutes ago, EvilSpike said:

 

Small it is not. Take the propshaft (or just the pins out of the front hex adaptors) out of the thundershot and see what a complete nightmare it is to drive quickly And accurately in 2WD...

That is true. There is also a big difference between a car designed as a 2WD, and a 4WD car being made to run in 2WD. My DT-02 runs rings around my DF-02 relieved of half its dogbones for example.

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18 minutes ago, TurnipJF said:

There is also a big difference between a car designed as a 2WD, and a 4WD car being made to run in 2WD.

Very much so. I took the propshaft out of my Terra Scorcher as I thought it would be fun.

Hey, it's not like being wrong is a crime or anything...

 

 

Edit: Actually, it was fun driving the car around in 2wd mode, but that's because it was a lot more difficult to keep it from spinning and sliding everywhere. It's a giggle doing massive unexpected power-slides and donuts when you're just messing about, a pain in the wang when you're trying to get as many laps in as possible inside of five minutes...

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I definitely feel that at the moment I am the limiting factor rather than my cars and I have reached a level of xx laps being possible on a given round with my driving style, concentration, eyesight, reaction times and consistency.

For example, without doing any practise runs, my first postal race attempt always results in a lower score than my final attempts BUT it is not actually that far away. On all the rounds so far my initial 'banker' attempt has normally been less than 0.5 seconds a lap or 2-3 laps short of my best attempt. The best attempt may come after hundreds more laps. So I only see a very small improvement in my lap times regardless of the number of laps I do in practising a round.

I believe my cars, especially the modified Thundershot and the Avante2001 are easily capable of at least 2-3 more laps per round than I am managing, in some cases as many as 10 more.

This born out by the fact my youngest daughter with a stock silver can thundershot has come within 0.5 seconds of my best lap times on two rounds. Depends on the track and surface though. She is more consistent and quicker on tarmac than grass, and on small twisty tracks than fast ones.

Today I managed to get just 2 laps less on wet grass in the same buggy (other than tyres) than I managed to get on dry tarmac. Now you could argue that historically most of my driving has been on dirt so I should do well there, maybe so, but I still find it rather odd that I am unable to achieve far higher lap counts on the grippy dry tarmac on super soft compound sticky tyres than I can on wet grass. Further evidence that I have hit a ceiling for my current skill level rather than a ceiling of the cars outright performance - oh and to add insult to injury, other than a tyre change, the car was still running a full tarmac setup with very low ground clearance, firm road biased shocks and taller road biased pinion! Had I set the car up for the grass I may well have matched or even beaten my tarmac times!

I did the grass race just 30 mins after the tarmac race so I can't even say it was day to day variances in my driving! :)

EDIT: @TurnipJF, I too have a similar issue between two of my cars. My Avante2001 is essentially an Egress with a different shell, it is full carbon and has all the technical improvements that were done to be a good race machine (mid motor, longitudinal battery, centre diff, more efficient drivetrain etc),  yet there are only 1 or 2 laps difference between it and my thundershot (essentially a basher) in most of the rounds so far. In fact the thundershot has beaten it in just about every round. This is just not plausible on paper. So I think it is just that I'm incapable of extracting the performance from the Avante2001/Egress that maybe somebody like Lee Martin could? I find that the very high performance cars are a bit twitchy/nervous and require far more concentration and skill to control at speed than the more forgiving Thundershot. So at a certain lap time I start to find the Avante2001 becomes too much for me to handle despite it having far more to give in the right hands. 

EDIT2: Just checked the specs of your GT tuned again, there is no question, my thundershot is by far the quicker buggy, almost twice as fast. Mine has been GPS'd at 43mph max speed (although we'd never run that high a pinion in racing). I don't own a GT tuned but I have run a Kyosho magnetic mayhem truck motor in my thundershot in a previous round and a GPS test showed a maximum speed of 25mph. After comparing the specs, the Mag Meyhem is very similar torque and rpm to the GT tuned. I know for a fact that I gained 0.3 seconds per lap by lowering mine too so add that on top of the speed difference and it is likely to be over a second per lap faster than the GT tuned thundershot running standard ride height. And yet yours has still beaten mine in two rounds now? That tells me your driving/skill level is probably at least 1 second per lap quicker than mine. So my skill ceiling is a lot lower than yours but I guess we all have a ceiling. I'm now 52 so reaction times nowhere near as good as when I was in my teens and twenties and I have not raced regularly to maintain those skills either. This leads me to conclude that in your hands my thundershot may well be capable of doing 7.2 second lap times on round 5 in your hands, maybe even faster. I will have to wait to see how your thundershot has done. :)

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@TurnipJF Perhaps there is a Driver's Threshold... I've a feeling that you haven't reached yours yet. 😉 

There is a physical limit that something like a RC Car can reach. There's only so much grip tiny Tires can achieve, given the small amount of weight they carry. Very light weight only seems to be a factor in 1:1 Racing.... 

A 1600lb Ariel Atom or 1400lb F1 Car can easily out handle a 3000lb Porsche, despite Tire Compounds. Thing is, these factors don't directly scale down. The Atom is still exerting more pressure on its Tires than a M Chassis Car or RC Buggy ever could.

I'm so bored right now that I could go through the physics of it all... but it's redundant for your purposes. 

In the 1/10th Scale World, things can get odd. That Thundershot WILL out handle a few bespoke 1/10th Scale Race Cars - with equal Tires. The wider Track IS a factor, as well as 4X4. Buggies also have quite low CoG. One would THINK that 1/10th High Performance TCs would be the best handling Cars - but physics says otherwise. Those were meant to be SCALE representations of their 1:1 counterparts. As such, they're underweight, under Tire-ed, and overpowered...

That's always been the challenge of RC TC Racing, and why I believe it's so popular. RC Buggies, really reached the peak of their development by the late 90's. They handle phenomenally, but there's no quantum leaps left for them.

It's possible that you could set an unbeatable Record, if you had a properly set up Team Associated RC10B74 4X4 Buggy..... But in a way, it takes all the challenge and fun out of the Postal Challenge.

Wouldn't it?

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