Hot Bodies D413 1/10 4WD Buggy

[adam_u]

Thanks for the update, Rich.

I see you've now gone very heavy on the centre diff oil, as I believe you had come right down to about 40k - was this after Kidderminster or have you been running elsewhere?

Maybe I will leave the 100k that I built it with in for it's first shakedown on Sunday...

[Richard Lowe]

Originally Posted by adam_u

Thanks for the update, Rich.

I see you've now gone very heavy on the centre diff oil, as I believe you had come right down to about 40k - was this after Kidderminster or have you been running elsewhere?

Maybe I will leave the 100k that I built it with in for it's first shakedown on Sunday...

The initial running we did with the car the thinner oil felt a bit better, however at Southport a couple of weeks ago when it rained and the grip went right down I could feel it making the car do strange things being so thin. I'd only ever run <100k up to that point so I thought I'd try the heaviest oil I had and it was instantly miles better, much more stable and consistent. Going thicker did slow down the low speed hairpin rotation a touch, but it was still better at this than any other car I've driven. I was worried going thicker would make it more prone to wheelies but it's actually pretty much the same as with the thinner oil which surprised me a bit.

The shock piston changes have made a big difference, the initial setup I posted for RHR had a bit too much pack for such a light car which was good on the smoother flowing RHR layout but come Kidderminster and Southport it made it a bit of a handful over the bumps.

[mes]

Richard,
did you drill the kit blank pistons or did you use e.g. Associated ones? I am very interested in this car although my driving style does not suit 4WD at all.

[Richard Lowe]

Drilled the blank pistons that come with the kit

AE pistons wouldn't fit, the HB pistons have a smaller hole for the shock shaft as they mount with a tiny locknut rather than e clips.

[mes]

I see, thank you!

[Pedros20]

Here's mine all wired up & ready to go.
Should be Wednesday, RHR or Mansfield depending on the weather.

[mrroy76]

Hi, well im probably the first Norwegian driving the D413 and today where my first race with it. I have not had any time to practice with it because i came home from the US on friday and a friend of mine built it so it was ready when i came home. I have not drove any 4WD at all this year so i was also out of practice.

So i ran this setup http://www.petitrc.com/setup/hotbodi...owe_RHR201404/

Under the qualifying rounds i did a couple of changes due to traction roll and the rear felt kinda hard on the rear bumped up sometimes on minor bumps.

What i did to prevent the traction roll where moving the upper rear shock mounts one slot inward. I also had camber both rear and front to -2

For the rear shocks i switched to 25 losi oil. It got alot softer on the rear. The buggy runs really good but the driver where so out of shape compared to my 2WD driving.

Where i need to play some more is with the diffs. It also got a bit rainy and it then became very loose in the rear.

My impressions about the buggy so far is awesome.

In 7 heats i did not break a single part on this beast. So no doubt about the rigidity here. The only thing i noticed as a weakness was the pins that holds the wing in place. 2 times they popped out and 1 time the wing fell of.

I must say that i overjumped alot due to the power difference between 2WD and 4WD, and it bounced in all kinds of directions. slamming really hard sometimes.

My biggest worry is the shock caps. And the big opening in the front when it rains. Today i use some ductape to cover part of this opening from spinning water from the front tires when turning.

The surface we have is smooth high traction astro. really short grass. And we have some big jumps. I cant wait to get some more practice with this buggy.

Cheers
Roy

[Richard Lowe]

Hi Roy,

Try my current setup next time you run the car...

http://www.petitrc.com/setup/hotbodi...hport20140504/

We've learned a lot since the first test day at RHR. The car's now much easier to drive and more plush over bumps, but still feels super light on it's feet and agile

Rich

[mrroy76]

Originally Posted by Richard Lowe

Hi Roy,

Try my current setup next time you run the car...

http://www.petitrc.com/setup/hotbodi...hport20140504/

We've learned a lot since the first test day at RHR. The car's now much easier to drive and more plush over bumps, but still feels super light on it's feet and agile

Rich

Thx, i have a order of springs comming here tomorrow. I will certainly try this setup and post my feedback on it. And my adjustments if there is any

By the way, you kept the same shock mount in rear, you dont get traction roll? Maybe your springs is softer then the originals?

You can see our track promo here to get a feel of the surface, especially after 1:40 you can see some short great rc action https://www.youtube.com/watch?v=64_9VO8A_lc

[Balders]

Anyone with a 413 going to be at the Oople race this weekend?

[Richard Lowe]

Originally Posted by mrroy76

You can see our track promo here to get a feel of the surface, especially after 1:40 you can see some short great rc action https://www.youtube.com/watch?v=64_9VO8A_lc

From the video that doesn't look especially high traction, you should be fine with the Southport setup

The current thing I'm experimenting with is the front shock position on the tower. We moved it right to the inside hole when we were running the stiffer pistons during the first test and left it there, though after doing some more mileage I'm finding I prefer the standard middle hole as it supports the front of the car better in roll.

Next on the list is heavier front diff oil, I'm finding that I'm mostly dialling initial steering out and mid-exit steering in to the car. I'm now to the point where it's starting to get a little pushy on exit, going up to 10-15k in the front should get some of that exit steering back. Though I think that might make it a bit much for most people, I like a car with all the on power steering I can get (then some more )

[Muzzie]

I ran mine last night (Indoor) with 15K Front 100K cen and 5k rear and the car was great. All I had to do is let go of the power, turned in, then back on the power mid / exit of the corner. It was like a bullet out of a gun down the back straight.

I still like the kit pisions (4 hole 1.3mm) the car changes direction really well.

[mrroy76]

Originally Posted by Richard Lowe

From the video that doesn't look especially high traction, you should be fine with the Southport setup

The current thing I'm experimenting with is the front shock position on the tower. We moved it right to the inside hole when we were running the stiffer pistons during the first test and left it there, though after doing some more mileage I'm finding I prefer the standard middle hole as it supports the front of the car better in roll.

Next on the list is heavier front diff oil, I'm finding that I'm mostly dialling initial steering out and mid-exit steering in to the car. I'm now to the point where it's starting to get a little pushy on exit, going up to 10-15k in the front should get some of that exit steering back. Though I think that might make it a bit much for most people, I like a car with all the on power steering I can get (then some more )

Well its actually very high traction when its dry i have to cut 3 rows on each side for the front tyres and also have tyre glue after dremel has polished away the stubs after cutting. On scumacher mini pins yellow.

Im heading there tomorrow for some testing, the only thing ive done since last weekend is changing the front to 7k instead of 15k and center diff to 100k. Ig ot some other oils in the post office, like 300k so i pick them up tomorrow.

[mes]

Did you try some yellow Minispikes? All that cutting and dremelling must be annoying...
At our NORC race in Langenfeld last year, grip was ultra-high. My son kept traction rolling with Minipins and Multibytes, but otherwise the car was dialed. Some slightly to (in the course of the weekend) well worn Minisipikes solved the problem, and the car was perfect! (B-Max4 with Jörn Neumann's Maritime set-up iirc)

[mrroy76]

Originally Posted by mes

Did you try some yellow Minispikes? All that cutting and dremelling must be annoying...
At our NORC race in Langenfeld last year, grip was ultra-high. My son kept traction rolling with Minipins and Multibytes, but otherwise the car was dialed. Some slightly to (in the course of the weekend) well worn Minisipikes solved the problem, and the car was perfect! (B-Max4 with Jörn Neumann's Maritime set-up iirc)

We do race minispikes sometimes, but not when its at its highest traction. I dont know the length of our astro grass, but its really short, and with a few raindrops it gets slippery. So alot of us do run minispikes when the grass is starting to dry up. on wet its usually ballistic minispikes (green)

[Balders]

Had a first proper run outdoors over the weekend at the oOple event Mendip. Jimmy took a few photos of the car so hopefully he'll do a mini write up in his report..

Rich, I was using your setup and it works very well on high grip however, I did REALLY miss a slipper clutch, being able to quickly make the adjustments to calm the car down as the grip changed through out the day would have helped. I was using speedo settings in the end calm things down but even that was a bit hit and miss.

Gearing up more was the next option but was running a 7.5 on 28t pinion and didn't have anything larger.


Anyone else missing the slipper clutch?

[Richard Lowe]

What are you using ESC wise, I can post my HPI Flux Pro settings if that's helpful?

I used to run the slipper in my B44 just loose enough to stop the plastic gears detonating, when I put Durango diffs in it I just cranked it all the way tight - so for me it's been one less thing to go wrong

What aspect needs calming down?

[Balders]

thanks Rich.

V3.1 Hobbywing so pretty much the same as a Flux i believe.

From memory as its not in front of me, it was set something like 1st punch 5 second 15, 4" boost 15 turbo after .5 full throttle.

I was struggling with my un-cat like reactions at times to get the power down smoothly and had a tendency to over cook on the tighter sections. With a slipper I feel i could have backed it off a little and smoothed out the power delivery which may have helped. I should have dropped to a slower motor like a 10.5 and pumped the boost up for the straight but didn't have one to hand.

other than that its a good car, I'm really enjoying it.

[mrroy76]

Hi. Yesterday i did some more testing had changed my diffs from 15 to 7k in front and from 40k to 100k all associated oils. Still 10k at rear.

I run it with a 5.5 turn engine and 24t pinion. The sun where shinning and we had really high traction. I experienced that the front wheels lifted from the grass . Why? Is this because of to thick center oil?

Well i did feel the new setup where a bit off, did not feel comfortable with it, the buggy is quite aggressive and i overjump alot. So im concidering a change from 5.5 to 6.5 to calm it down a bit. I`m really not sure what to try on the diffs, i see some of you guys run 300k in center, but wouldnt that give me more front wheel lift? I think im going to try 10 or 15 k at front again and 5 or 7k in the rear.

Im also wondering about the front end of the buggy, and the steering, it is alot of slack between alot of the parts even if the screws are at bottom. So i dont know if i need some thin spacers to get rid of the slack? Because we can really see the front wheels are a bit shacky.

[Richard Lowe]

I'll have to check what I'm running exactly on the ESC, I do remember I'm on 5 1st punchrate and 10 2nd with a 6.5. IMO 5.5 is too much motor for the car in shorty with it being so light, not that it can't handle it just it makes the car too fast and aggressive to be properly controllable through the infield.

Over the years we've all got used to our 4wd's getting heavier and heavier and cramming more and more motor in to make them fast enough. The 413 being so light doesn't need as much motor to be quick in a straight line. At Southport in the finals starting 10th, in each of the legs I was at least alongside the car in front half way down the straight and having to back off not to plough into the back of people

I run it with a 5.5 turn engine and 24t pinion. The sun where shinning and we had really high traction. I experienced that the front wheels lifted from the grass . Why? Is this because of to thick centre oil?

Too much motor

The car is very light and shorter than most of the current 4wd's which makes it ideal for pulling wheelies! If it had a slipper and if it was set right (just loose enough to protect the drivetrain a bit) it wouldn't stop it wanting to pick the front wheels up. What you will find though is you're accelerating much faster than other cars, even if it doesn't feel like it.

I think most people will be happiest with a 7.5 or 8.5 with the car in shorty, it'll still be plenty fast enough and much more controllable than the 5's a 6's that are the norm. In my experience so far I'm 1 or 2 turns slower with the same electrics compared to what I ran in my B44, anyone that races at York indoors that has seen my car over the last few weeks with a 6.5 in compared to the 5.5 I used to run in the 44 will verify it's plenty fast enough