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Old 04-03-2009, 08:10 AM   #1
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Default Driving style going from brushed to brushed equivalent...

Has anyone found their driving style altering with more power at their disposal, (backing off the throttle trying to get the power down, or being more aggressive using the power how it comes) or have you cured it by finding a better chassis setup?

I've seen a few guys very on off with the throttle trying to get the power out with brushless, hence my question.

I'm also having a lot more speed now going from 27t to 13,5 so much so that the car is trying to rotate quicker through the apexs and grip rolling more often than not. (10x15m medium to high bite carpet track on foam).

So far, I am looking at taking out front toe, and experimenting with other things, such as less additive on the front, taking off the roll bars and looking into roll centre more carefully.

I also went from a centre one way to centre fixed drive.
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Old 04-03-2009, 08:19 AM   #2
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When I first got back into touring I was running a 27t against several 13.5 cars. They are not the equivalent they were once thought. The 13.5 is much more torque than the 27t. A 17.5 is a much better match.

I really cant help you on set up. Im not sure that it would change much with more power. It simply becomes more important that you have a good one. Does that make sense?
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Old 04-03-2009, 08:27 AM   #3
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Yes, I do see what you're saying there

With 27t, I needed as much speed as I could find on the apexs, hence the one way was working well to carry the speed through the corner.

Now, even with a fixed drive to slow the car down a little off throttle, I am still too fast going into a corner, and the car unsettles itself.
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Old 04-03-2009, 08:49 AM   #4
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Are you running on the rug or on pavement?
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Old 04-03-2009, 08:54 AM   #5
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Old 04-03-2009, 08:57 AM   #6
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As said, the 13.5 makes more power than a 27T brushed, so yes, you setup will need to change.

The biggest difference I had going from brushed to brushless is as you've found, with the rear unsettling as you apex.

Keep in mind that brushless motors have next to no natural drag brake compared to a brushed motor. Basically with a brushed motor, you're either accelerating, braking lightly [neutral], or braking heavy [obviously brakes], unless you add some push or other ESC setup that I'm not going to get into.

With brushless, you can accelerate, coast very freely, or brake.

This difference means weight transfer is much more gradual, and will actually uncover shortcomings in your setup.

For myself, going from brushed to brushless, I had to [in this order]: add more rear droop so I could better see what the chassis is doing without spinning out, and then work on getting a good balance. On my car, that involved standing up the front shocks almost vertical, and playing with the rear shock angle to neutral out the car.

This added just a hint of push off throttle on corner entry, allowing you to enter very aggressively, a slight oversteer mid corner neutral power/gradual accel, and neutral handling at corner exit putting the power down.

Your preferences may differ, but I can drive my car very aggressively, put it where I want, and have it stable anywhere on the track. I'm also running a very stiff diff up front, and tuning my mid-corner/corner exit oversteer with the rear diff tightness.

Good luck, hopefully that all made sense.
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Old 04-03-2009, 09:14 AM   #7
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Quote:
Originally Posted by HarryLeach View Post
As said, the 13.5 makes more power than a 27T brushed, so yes, you setup will need to change.

The biggest difference I had going from brushed to brushless is as you've found, with the rear unsettling as you apex.

Keep in mind that brushless motors have next to no natural drag brake compared to a brushed motor. Basically with a brushed motor, you're either accelerating, braking lightly [neutral], or braking heavy [obviously brakes], unless you add some push or other ESC setup that I'm not going to get into.

With brushless, you can accelerate, coast very freely, or brake.

This difference means weight transfer is much more gradual, and will actually uncover shortcomings in your setup.

For myself, going from brushed to brushless, I had to [in this order]: add more rear droop so I could better see what the chassis is doing without spinning out, and then work on getting a good balance. On my car, that involved standing up the front shocks almost vertical, and playing with the rear shock angle to neutral out the car.

This added just a hint of push off throttle on corner entry, allowing you to enter very aggressively, a slight oversteer mid corner neutral power/gradual accel, and neutral handling at corner exit putting the power down.

Your preferences may differ, but I can drive my car very aggressively, put it where I want, and have it stable anywhere on the track. I'm also running a very stiff diff up front, and tuning my mid-corner/corner exit oversteer with the rear diff tightness.

Good luck, hopefully that all made sense.
It did, thank you for sharing your findings I shall be doing more experiments tonight!
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Old 04-03-2009, 09:31 AM   #8
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Experimenting is my favorite part of this hobby.

I had another thought, if guys you run with are driving very on-off throttle, they're probably trying to force the chassis to work the way it did with a brushed motor. By the time you're done tweaking your setup, you should be able to drive similar to brushed power, with easy rolling on the throttle on exit, and coasting into corner entry, albeit with higher corner entry speed due to less drag brake.

The only time I use the brakes at my local carpet track is diving in WAY too deep trying to make a pass, or avoiding an incident. Usually tire scrub on turn-in is all the braking I need, and pick the throttle back up at the apex.
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Old 04-03-2009, 09:39 AM   #9
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I like to experiment, buy only if I have a car that's already feeling half decent to start with

I am pretty aggressive on the throttle too, but the joy of that is I can tame myself down with the expo, or ESC settings if I need to.

Feathering the steering and wondering if it's gonna grip roll is not fun

...But it is fun seeing myself easily have the same amount of speed on the straight, with scope of more to come...
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Old 04-03-2009, 09:50 AM   #10
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Lol, I'm the opposite, I like to take a car that's utter junk and turn it into something When I first got the car I'm running now, it was set up for 19t foam tires and was a bit loose all over. Then I started by bolting up a set of 24 Sweeps, reset the ride height, installed an RS/17.5, and watching/hearing everyone in the pits either talk about me not being able to drive, or that the car was too old to be competitive. An hour of running and 5-6 battery packs being hot swapped later, some of those same people were asking for setup advice. A week after that I put the car in the A-main on my first competitive outing with it.

This week I decided there's bound to be more speed to be found, so I changed everything on the car, went to 28's now that the weather is starting to warm and definitely found more speed and grip because it will traction roll if I get behind on my steering and make a direction change too abruptly. I may try to tame it with more rear camber though, haven't really decided what I'm going to do about it, if anything since it's only resulting from my mistakes at the moment.
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Old 04-03-2009, 10:00 AM   #11
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I have been known to have 8mm ride height on foams before at a club meeting, and still put it in the A, it turned on a dime suprisingly! Flow, no flow, I just get the job done however the car takes it.

So, I just kinda put up with bad handling cars and work around it, unless its severe like this.

Excessive grip roll is a no no, I would rather eat my fingernails to the bone and pull my hair out first!!!

Well, its 5pm local time, time to put these theories to the test and get to the track for an evenings racing! Wish me luck
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Old 04-03-2009, 10:08 AM   #12
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Lol, yeah, get your ride height down to 5mm, put the work in and get a decent handling car.

Good luck.
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Old 04-03-2009, 07:03 PM   #13
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Quote:
Originally Posted by tc3team View Post
I have been known to have 8mm ride height on foams before at a club meeting, and still put it in the A, it turned on a dime suprisingly! Flow, no flow, I just get the job done however the car takes it.

So, I just kinda put up with bad handling cars and work around it, unless its severe like this.

Excessive grip roll is a no no, I would rather eat my fingernails to the bone and pull my hair out first!!!

Well, its 5pm local time, time to put these theories to the test and get to the track for an evenings racing! Wish me luck
Yeah, THAT will be a problem when you're putting more power through the car(as you do after switching from 27T brushed to 13.5 brushless motors), you shouldn't have to do anything radically different to your car, just get a good overall setup on it, because the extra power will exacerbate any flaws in a car's setup. If you're using one of the TRF 415 you list in your sig., try looking up some setups on TryHard's site( www.thard.co.uk ), they have a LOT of good setup info there for the 416 & the 415, & from there, just work on refining your driving line. Once you get comfortable with a good setup, you'll notice that you'll be going QUITE a bit faster than you did with 27T brushed(it's just a matter of dotting those "I's" & crossing those "T's"). that's how I dealt with it, wasn't a radical change, my car's setup & my driving just evolved to deal with the power....
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Old 04-04-2009, 08:30 AM   #14
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Quote:
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Yeah, THAT will be a problem when you're putting more power through the car(as you do after switching from 27T brushed to 13.5 brushless motors), you shouldn't have to do anything radically different to your car, just get a good overall setup on it, because the extra power will exacerbate any flaws in a car's setup. If you're using one of the TRF 415 you list in your sig., try looking up some setups on TryHard's site( www.thard.co.uk ), they have a LOT of good setup info there for the 416 & the 415, & from there, just work on refining your driving line. Once you get comfortable with a good setup, you'll notice that you'll be going QUITE a bit faster than you did with 27T brushed(it's just a matter of dotting those "I's" & crossing those "T's"). that's how I dealt with it, wasn't a radical change, my car's setup & my driving just evolved to deal with the power....
Well ive learnt that foams can be hard work, trueing, or getting them to stay equal sizes, but I need to keep on top of tyre rotation to do that.

Ive wound the droop screws totally out of the rear end, to see how the car is behaving, its better now but still likes to roll, high bite even without additive.... this car has plenty of rotation. I will need to take out the 1deg of front toe that is in too, and get the front kit roll bar back on, possibly.

Gonna get some 40/40 shore tyres or 40f, 37r and keep my quest on for some good times... 35f and 32r are just hooking up way too much.

Down.... but not out, hell no!
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