Fast enough to compete with a Mini-z

[LBRC]

First Dodge Shotgun NASTY Car.
http://lbspd.com/v-web/gallery/albums/album85/6_G.jpg

Fun set of soft rubber racing slicks.
http://lbspd.com/v-web/gallery/albums/album85/3_G.jpg

Body modified from a Windracer antenna decoration, note; not all will fit some are too narrow.
http://lbspd.com/v-web/gallery/albums/album85/4_G.jpg

http://lbspd.com/v-web/gallery/albums/album85/2_G.jpg

Back to the title I sent Epoch1-43 aka MZR a set of similar Shotgun modified cars to try out so I thought I'd post links, to some of the initial comments.

fast enough to compete with a Mini-z.. but we didnt
From Mini-ZRacer.com Event: 1/27/2006, Ann Arbor, MI (http://mini-zracer.com/forums/showthread.php?t=20550&page=3&pp=15)

Well I just go tback and they are still running. This thing was very fast! It was faster than a dialed MR-02 with Atomic (bushing) Stock motor. It had so much power the car wouldn't hook up because of the hard tires. BTW, we were running on RCP.
From Ripper7Racing.com: Waiting is Unpleasant, W/ link to Building a HP Epoch (http://ripper7racing.com/forums/index.php?showtopic=5257&st=0&#entry54186)

Link to my photo gallery "Building A HP Epoch" (http://lbspd.com/v-web/gallery/album80)
Note: There are in-depth descriptions under most of the photos; to see more than a title you have to click on a photo thumbnail, once you see the a full sized photo then scroll down to the description section below the photo. The Gallery is divided into albums with sub or nested albums so when you click on a album thumbnail it opens the nested album.

[LBRC]

Sorry for the double post but I had too many photo’s, hopefully we will get to see some photo’s form the Ann Arbor GTG with the car in action.

The above comments referred to a car running a 19K dual motor set with 8 tooth pinion gears. I also sent a car with a somewhat more powerful 22K motor set and 7 tooth pinions.
The mount on the chassis shows a 22K motor set with 7 tooth pinions, the lower left is a 19K motor set with 7 tooth pinions, and the right is a 19K motor set with 8 tooth pinions.

http://lbspd.com/v-web/gallery/albums/album85/5_G.jpg

I also sent Steelwoolghandi a similar car as a trade for some custom painting, I hope he doesn’t mind but here’s a quote form a PM about the car:

I really like this car I have been having a lot of fun with it, I almost beat my nephew's X-mod he had upgraded it to a 6 cell and its fast but the Epoch was right there with it the whole way.

The big thing is you were right you have to weigh down the back we actually took the cars to a nice skateboard park all concrete and lots of places to run the cars in fact a cool straightaway. The Epoch outperformed the X-Mod hands down but for all out speed he had me. But for me I would rather have better handling then speed. You could have the fastest RC car in the world but if you cant turn it all you have is a fast drag car!

The steering motor is much better than the standard Epoch motor more responsive. I think this car is a blast and have had a great time with it. I personally would not change a thing (well except the weight issue). I think putting a spring between the motor section and chassis would help keep the back a little tighter and I might not have to add any weight? the problem I am having is the back bounces to much it causes the back wheels to hit the wheel wells. I might try something to see if I can get it to work I will let you know!

Hope to hear more about the cars as they get driven and run through the ringer, good and bad, LoL bad is good if you don’t know what someone doesn’t like you can’t try to fix it. They do take a little getting use to, you can’t just pull the throttle and steer even on a 2L RCP track with these cars you have to work the throttle.

[hobbycar]

LBRC, we ran your super custom lipo dual-motor epochs at our Minizracer.com Ann Arbor GTG yesterday on the RCP track and it is fast. Took some skill to keep it from flipping but it could stay with the Mini-Zs on the straights. Definately tons of speed.

I have video and I'll post it when I get it resized accordingly.

Great job!

-hobbycar

[LBRC]

Hey great, which motor setup did you like best the white pinions with red end-caps, or orange pinions with orange end-caps?

Did one have noticeably better handling?

Was one faster?

[Draconious]

Umm... how well would it run with just one of the these motors in it?
most likely the torquiest...

I want some cars that run longer rather then go faster, but a hair of speed increase would be ok.

[LBRC]

One motor turns out to be a very poor choice, too little power.

Two motors = just the right amount power (not speed).

One motor = 1/2 the needed power so you not only get no torque, the motor also gets too hot, and coreless motors especially small ones don’t do well hot, creating heat instead of motion uses up more battery power than two. Additionally for your effort you get to burn the brushes off, just the motors little way of letting you know it had to work it too hard.

That’s the bad news the good news is that with the turbo’s power efficiency, the ball bearings, and the coreless motors running at max efficiency you get much longer runtimes too, sort of a win-win situation.

Especially with the Kan 180’s or the LiPo battery packs these cars have a much longer run time than stock. LoL last summer I ran an early dual motor version on my track for over 50 minutes straight with an E-Tec 420 LiPo pack, made me want to paint a body pink and put an energizer sticker on top, it just kept going and going. Not sure how the two cars I sent to Ann Arbor are actually doing in the runtime category, but they should be getting at least 10 to 12 minutes when double charged on a Epoch charger, 12 to 20 minutes on a peak charger with the Kan-180 NiMh battery packs, and a solid 30+ with the one 340 LiPo pack I set. Runtime is also dependent on how much wall bashing and/or wrecking you do.

The dual motors turn out to be very efficient especially once moving, not just fast. Think of them as a turbo charged small block, it can be fuel efficient but when you step on the gas it can also really fly. What it’s not good at is going up hill or pulling a load, that’s where a larger slower rpm motor with more torque would be more efficient.

[Draconious]

I figured they would burn, but I do not want the car to go any faster... for my purposes (rookie drivers).

I guess I will just try to find a larger corless lol :) Or use the stupid stock...

I would have one fast for my own use but thats about it.

Have you tried putting a capacitor in parrelel with the batteries on a stock epoch? To keep it more stable when the voltage gets lower?

[LBRC]

You’ll need a motor that reaches it’s max efficiency at about 14 to 17K rpm at 3.6 volts, Apex has my first set of test motors (green end-caps) they where just a bit hotter than the green Super Slick motors but I’m thinking that two green super slick motors in a shotgun mount might do as long as the brushes held up. Maxon makes a 10 mm x 17mm coreless that’s just what your looking for but spendy at $50 and mounting is just a bit tricky with ball bearings, although not so bad without.

[hobbycar]

Okay, video.google.com is still verifying the video. Until they okay it you can find it here on my server until my IP Address changes:

http://68.73.192.2/miniz/super_epoch_solo1000K_320x240_noaudio_001.mov (12 MB)

BTW Drac it was a bummer you didn't make it to the Ann Arbor GTG. Okay could of drove them yourself :D

-hobbycar

[LBRC]

Nice little video, do you know which car that was, red or orange motor?

[hobbycar]

Nice little video, do you know which car that was, red or orange motor?

It was the one with the orange gears but I can't remember what motors where in it.

[LBRC]

The orange gears go with the orange motors, did anyone drive the other car?

[arfin]

Nice video, wish you had it racing a Mini Z. Looks damn fast, even on that huge track it does laps in no time.

[hobbycar]

Nice video, wish you had it racing a Mini Z. Looks damn fast, even on that huge track it does laps in no time.

Oops. I actually posted the wrong video :confused:

I do have a video of it running with Mini-Zs. I'll get that one up later.

We did drive the other one; the other one seemed faster and harder to control because of the speed. And soon we had an issue with the rear suspension. It was probably something that we could have fixed in 1 minute but that would have been one minute less of driving :D

I'm sure we'll get a chance to drive both again at the next Ann Arbor GTG.

-hobbycar

[LBRC]

Can’t wait to see one on the track with a Mini-Z.

The red motors have a lot more torque than the orange motors, don’t know if it has a higher top end or not, hope the handling is just the diff and not the greater current drain though.

Last summer while testing my first versions I just swaped out the differential if there was a problem instead of spending driving time fiddling with one that was binding or sticking and fixed it later.

I am working on a few differential fixes. One promising idea that I want to try is to replace the crimp bead with a 0-80 nut threaded onto the axle, the nut would be stainless steal the same size as the bead with two flat sides, so you could simply unscrew it to clean the diff. The big one of course is that I now have a working ball diff that is showing a good deal of promise. And fortunately it wont be long before I can set my track back up.

[hobbycar]

Here's a link to the video of the Super Epoch on the track with Mini-Zs.

http://68.73.192.2/miniz/super_epoch_vs_miniz1000K_320x240_noaudio.mov (12MB)

[LBRC]

That was great, almost laughed myself off the chair, like some spastic overenthusiastic mouse. Defiantly have to get to work on the diffs.

[cdog4w]

Nice video hobbycar, thanks for posting. Really helps people to see whats going on with LBRC's work. So it looked like the epoch was lapped about 3 times by the yellow Z, did you guys go for a full race or just shoot some video and do some driving? Be curious to see how the epoch would hang in a 5 min race or something like that.

As for performance, it was definitely as fast, but a lot less stable. I'd assume some extra wheel time would help. I'm also hoping that LBRC's balldiff will make the cornering smoother which should make it much easier to handle too.

So LBRC, assuming one could find a 0-80 die, could we just thread our own axle or did you have to replace it with a whole new axle? Would be a nice mod for the cost of a die, or maybe sell prethreaded axles. Good fix until your balldiff hits primetime!

[hobbycar]

No prob on posting the video (props to Brad for shooting the vid while we were driving the cars :))

A couple things to keep in mind in watching the video.

The 3 Mini-z's in the video have been "dialed in" for the RCP Track (including using minizracer.com dry race bearings available in the Shop), were using stock mini-z motors, were driven by 3 really good drivers all with either Airtronic M8 or M11 Controllers who had spent the previous 4-5 hours practicing and racing on that specific RCP track :D

I was driving the super epoch using the stock Epoch controller and was driving it for the first time that night (starting at 1am that morning :D).

The video mostly shows the 3 mini-z guys having fun running with each other (not a timed race) and I grabbed the Epoch and jumped in to see how it would do.

I wish I would of had the chance to get another controller (e.g. the stock Mini-Z Prefex Tx) and dial out some of the steering. Or maybe put the body and wide Spec "1.5" tires I have from the Epoch Speed Racer set I bought 3 years ago. This will have to wait until next time.

Overall I think the car is AWESOME! Keep up the great work LBRC.

-hobbycar

[hobbycar]

The videos are finally approved on video.google.com:

Super Epoch solo run (http://video.google.com/videoplay?docid=-8566776847438976536)

Super Epoch vs Mini-Zs (http://video.google.com/videoplay?docid=-8443467152185546624)

[arfin]

Videos are great! I've never driven a Mini-Z before, but they seem fast stock, are they faster then an Xmod stock? I'm surprised it wasn't flipping when turning at those speeds.

[hobbycar]

Videos are great! I've never driven a Mini-Z before, but they seem fast stock, are they faster then an Xmod stock? I'm surprised it wasn't flipping when turning at those speeds.

I'm not sure about straight line speed how fast the Mini-Zs are compared to XMods but they are definately faster around a track.

Mini-Zs are great and you can read more about them at minizracer.com forums (http://www.mini-zracer.com/forums/) which is run by the same guy running these forums.

-hobbycar