1/10 RWD Touring Project
 

Starting my 2021 racing season by using a 1/10 rwd touring car in a field of 4wd Awesomatix etc. Ended the day with a 14.8s vs 14.1s for my 4wd. Looking good for a first time try and will post updates on this thread for those who love RWD. Learned a lot from this shakedown and in process of building a better rwd using a different chassis. RWD brings back my enjoyment of the hobby and looking forward to 2021. Cheers.


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Congrats on getting so close to the 4wd times!

Looks Tamiya M-04 based? TL-01 LA arms?

Tamiya M04 stretched to 254mm with stock TL01 LA rear and stock arm front with TB02 c-hub. Speaking of TL01, made my daughter race the TL01 and qualified 5th in the Amain in a field of Awesomatix, Yokomo etc. extending to the C-main. Not bad for a 1999 car in 2021, but have to admit the high cg, drivetrain friction, front end geometry and scrub is it's limit. :D

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Have a look at the Masami (https://youtube.com/c/MasamiChannel) and Masaaki Hirosaka (https://youtube.com/c/MASAAKIRCCHANNEL) YouTube channels... they have been working on something similar using an Snrc R3G (looks like a eco MTS touring), removed the front drive trains, and then made a custom front end with fibreglass.

They are utilising a Gyro, but honestly, looks quite good. And very close on laptime (think 4wd did a 9.0, the red a 9.8).

Lovely M-04L or Super L! I took mine out of long hiatus on a freezing day and it ran exceptionally well. I wish I could run it on a track. What is your diff setting?

Yes I've been watching their videos. I asked Masami what the laptime was without a gyro, and he mentioned it was 5 seconds slower :D

Stock gear diff with maybe 10K diff oil (but eventually leaks out).

Time to get more serious for Saturday's race. 1/10 Sakura Zero RWD. 40/60 weight balance and 120gms lighter than M04TC with better suspension geometry. Surpass 21.5 and HW Extreme blinky esc. Total race weight is 1,200gms. No gyro. :)

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Managed to qualify 4th on the grid in the A-main. It's a start :D

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Jan 30, 2021
Sakura Zero (Nsx, 1200gms) - Felt traction limited and weak power (Turnigy 3000 is light 150gm but weak). Understeer entry, oversteer exit. Vague steering feels delayed. From low to high grip times were the same, Q1 was fastest. Maybe cold weather, less tire grip (not reaching optimal heat for grip). Different tires/inserts all gave similar lap times. Removed rear anti roll bar (rear to slide with it). Far from traction rolling (need to generate more side grip and rotation).

Far from the rotational feeling of Xray with Yokomo BD10 springs. Must perfect suspension package before giving up.

Sakura D4 - Rear spool with soft setup somewhat drivable (20s/lap). When hard springs impossible to drive too twitchy. Abandon rear spool setup idea.

For Next Race: Slightly soften the diff. Add rear anti-squat. Increase front roll center by 1mm and rear by 0.5mm. Build tires with large air gap and no offset (gap between insert and tire). Bigger battery (more power and heavier weight for traction). Try combo of raising suspension arms and softening springs. Maybe lean front springs to make more progressive. Make front narrower at hex by using 24mm TC rims with 0 offset. Tighten rear belt.

:)

Very nice but would an open diff help? I would try that as a baseline and work my way up tightening the diff.

Open diff is easy to drive but slow on-power exit. Yes, softening the diff slightly is one of the things I will do :)

Finally some success. Finished the 3 A-mains in 3rd, 7th, 1rst. Nice to know my RWD can now put up a decent fight. Main changes I made were softer diff, more rear toe in, and just fine tuning springs. Front ride height around 7mm and rear at 5mm. Started the day with 20grams of lead weight in each of the rear hubs, then later 10grams as grip came up. No gyro.

Wireless scales for tech inspection :D

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RWD is allowed to be as low as 1200grams. Currently my car is a fat 1346grams.
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Ignore the name, I was driving but transponder record still tagged to my daughter. Won the 3rd Amain and set the fastest lap (against 4wds).

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At least getting better each time out. But very tiring to drive :D

Nice project! I tried a RWD TC a few years ago and it was definitely a handful to drive. I started like you, with a shorty shifted back and my ESC behind the motor but the 63/37 weight ratio just didn't put enough weight on the front end. No matter what I did to the frond end, I felt no difference on the track. At 55/ 45 the car felt MUCH better. Lots of rear toe-in helped too. Anyway I like your projects a lot, keep it up!

What corner weight scales are you using that are wifi/Bluetooth?

Skyrc