Want to start a brushless speed demon.
 

i had a project in mind and i seem to be having some trouble getting started, i posted questions about it in the rcuninverse.com and they say to start a post here about it cause rc-monster is all about brushless.

my problem starts with what rc to use, i was thinking 1/10 scale for speed but some were saying that 1/8th would be the way to go, here is the link to the other thread i started http://www.rcuniverse.com/forum/m_9017451/tm.htm im finding it hard to beleive that a 1/8th can make my 100+ goal the motors are made for torque not speed right. i also started to look at the 1/16th scale revo would it be possible with that? so what would be a good choice for starting this speed project? i don't want and onroad rc although i know that i could probably make the goal with one but there also limited to just on road, would like a off road one cause then when im not speed running i can play with it off road as well. any suggestion on how i can read my goal would be helpful, even some links that i could look at. if more info is needed let me know and i will try to get that. money isn't a problem cause i don't mind saving up cause it is just a project not a must have now, lol. so don't worry about price or buget

thanks

shark

Ofna GTP with a MMM2200 combo and some large 2-speed gears from RC-M.

Id think this over though as its very possible to go this fast, but parts will wear much faster and components are not going to last as long and if uve never drivin something this fast ur gonna crash it, id suggest something more reasonable like 65 with a efficient setup and also think the gtp 2 with a mamba setup is good on 5-6s.

GTP 2 converted to single speed (2 speeds and electrics = no good). I think the conversion gives you a center diff, lock that sucker up tight so you don't unload all of your power. After that a 2200KV MMM combo on 5-6s with proper gearing should push you to 80 without a hitch. Gear up some more and 100+ is possible but I think you should start off making runs around 60 MPH and work your way up from there so you can get a hang for the handling and get your car totally dialed in.

Electrics motors are definitely torque monsters, but that's not what they're all about. Basically your speed comes down to the overall reduction ratio and how many RPMs you're turning. Brushless motors have the torque to pull MUCH taller ratios than a nitro and can turn twice as many RPMs without a problem, so you're on the right track already just by ditching nitro for BL.

If you want all out speed, then build yourself a 1/10 dragster. 100MPH in 132ft.

The crt.5 is hella fun and can go stupid fast with foam tires. When you are done filling your need for speed, put on the offroad tires and have some more fun.

1/8 can go 100mph, but it just cost more. But like SPY said, learn to handle a car at 60mph and go from there.

so what kit would be the best kit, (please be specific as im still not familiar with all the names of different kits) would be the best kit to start with 60 and work my way up to 100+ with out have to buy a new kit every time i want to go faster? prefer off road cause like snellemin said when i done with my need for speed i can slap on some off road tires and have some off road fun. what motor would be good to start with?

still working with my savage x brushless but i think im going to keep that a basher.

Check out the net about speed Start here, one of our fellow posters
http://fastestrc.blogspot.com/2008/1...ph-by-nic.html

jze has/had the worlds fastest monster truck at 80+ some MPH and a guy here claims 90+ some with a revo. To break 100 with a 4wd you would be king, and need to be very rich. Think about your goal, money and have you gone 75mph ? I flipped my truck and hit myself with it and nearly broke my leg lol

im just asking whats your budget for this project ?

well considering that i don't mind saving up funds for this project, my funds pretty much limitless theres nothing that i can't save for, i don't have to have everything right away, but $600 to $900 for a kit would be a good place to start.

I am building a lightened g-maxx for this same purpose to enter it in a ISC event coming to my town. My goal is 100mph if a revo can do 91.2 a lighter , lower cog g-maxx cam probably do a 100mph. My biggest problem is tires and gear ratio.

sounds like fun, yeah the problem im having is i don't know were to start, lol. alot of people that i asked on another forum said a buggy would be my best bet, let alone the motor and esc. might try some proline street tires heard they were good.

well hope you acheive your goal man good luck.

taped HPI phatlines.

as for gearing, you might want to consider talking to mike- he might send you an rc-monster banner and some pinions :)




As for Shark.. your best bet is to find an 8th scale buggy... relatively durable (nothing is durable at over 50) and just work your way up from there

get a baseline setup for 60-70ish then work from there.


and make sure your tires are balanced or they will rattle the car to shreds.

1/10th scalers break too easily in my opinion to be a speed machine. I also would shy away from a revo as it's just not practical.

I am with the ofna GTP and MMM/2650 combo for all out speed. But as others have said, start with a reasonable goal like 65-70. I can tell you, just 60 mph is hairy with a little RC car.

In your original posts on RCU you stated you wanted to run 100mph on a somewhat gravel-ey road thats why you wanted a 4x4 truck. Most guys have trouble breaking 60 on a messed up road, and ALL speed records are on roads liking to a drag strip or an actual drag strip. Only way to do 100 with a truck IMO on a messed up road is a 1/6th FG with about 4 grand into it. If you can't drive your 1:1 car down it at 100 how can an RC. Fastest ive gone is 75ish with a losi speed T on 3s 4800kv geared so long my friends took it till I couldnt see it then said floor it over a radio and when it got near me it caught air and came flying at me like a pissed bumble bee. I can tell you when its going to rain now from my ankle thanks to that truck, I will never fix it. Nearly killed me lol... I agree GTP long gearing, but you wont be driving it on that messed up road. It will be flat pavement or nothing

well i wanted it to be 4wd drive cause i figured better control and partly the road and im a 4x4 nut lol, the road was made with glue and gravel there is no loose graval now its a pretty decent but nothin like a highway or freeway. so a decent 8th buggy and highest kv i can find? so basically it will be the bearing i use will be what gets me to my speed then?

dude sorry hear about ur ankle, i got in the way of my savage when it was still nitro cause it shifted ofv a hill scraped the hell out of my leg.

high kv equals bad


Low kv and more voltage.


and you should really look for a smoother test location. blacktop is best.

4000kv on 4S is the highest I would go in a GTP and the Tekin ESC handles it just fine. You would be able to push it harder with a high amp MGM ESC that Monster Mike sells.

Taped phaltlines are only good to about 75mph after that you need to glue 40# test carbon fiber thread fishing line on the out side of the tire. Custom foam tire on new pro-line vtr wheels is what I need. I sent mike a email telling him what I am planning I dont want any handouts but It would be nice if I could get a custom center diff out of him. If I break a record with his parts it could be good for business. A nice banner on my fifth wheel at the event. Magazine are going to cover it also. But if he is to busy to even answer my email maybe he doesnt need the extra business.

so this would be better? http://www.amainhobbies.com/product_...r-Combo-1350kV

then gear higher as i want to go faster low spur and high pinion right for gearing up, still not really understanding this gear up or down stuff. what do you up or down?


why do you glue fishing line around the ouside of the tire, the part of the tire that touches the road or were the wheel and tire meet?

I used motorcycle twist line.. what do they call it ? you know how you have to drill a hole through every bolt and nut and wratchet thin metal wire to keep them from falling apart to race on a track? I had my buddy twist that around my wheels back in 1995 (before i knew about taping or cared) 55 mph old ofna gtp nitro and it handled so well keeping the center of the tire stuck and sparked the whole time ( 2 bands on each side of the center line) poor mans double radial.. just a thought


it only really sparks at the bowtie knot that you have to tuck in ..its really sounding like a good idea, but im drunk

4S will work for a 1/10, but 1/10 involves alot of setup work to get it right AND stay on the ground at those speeds.

For an 1/8, you need to be at a minimum of 6S to even have a shot!!! I have personally done 80+ on a LOSI 8T running a 5S, 3500kv setup but it is a 1-2 pass wonder!!

If you want my opinion, and don't take it personal, it sounds like you do not really have a clue of how an RC reacts at the speeds you may have seen on videos or anywhere else. I suggest you get yourself a decent 1/10 sedan that you can get ALOT of parts for, drop in a Mamba 6900 or 7700 on 3S (yes it can take it!!), and get back to us after several flips, broken diffs, and a whole lot of headaches!!! THEN you will have a very small idea of what it will take to build a 100+ car.

I speak from personal experience and I can say that all the fun is trying to get there. I am sure that everyone here including myself are willing to help you out in any way we can, but I definately suggest you try something like what I described above to get your feet wet so you can really see if you want to embark on the wonderful quest of the ever elusive 100 MPH!!!:yes:

how comfortable are you doing custom work? if you want off road and 100mph here is what i would do.

losi 8t 2.0 Tekno brushless chassis and conversion kit with 44mm mount

losi 8b 2.0 buggy a-arms front and rear. put the buggy a-arms and CVDs on the truggy chassis so you have a very long but narrow and low off road car. (RCM member has done this)

also, you will need to run those GP rally 1/8 tires cuz buggy tires will just come apart. my losi brushless 8 2.0 clocked at 56mph and 3 sets of tires were destroyed just to hit that. both AKA and proline sets. 100mph is a lot tougher than you think just a heads up.

anyway, in the motor dept. i would run a Neu 1521 1.5d F on 6s lipo with 35c 5000mah rating. the MMM should be fine for the esc.

then for gearing take the 2 speed center diff from the inferno GT and mount the inferno gt center diff mount to your losi chassis. now you have a 2 spd. get the 2spd pinion from RCM with the tallest gearing possible and you should be good to go. even doing all this you will be very hard pressed to hit 100mph. youll have to make adjustments to the body or a custom body to avoid flight. also many other unforeseen challenges will occur i promise you.

i would probably even use the inferno gt shocks and mount them on the losi for super low cg. so all in all it wont really be off-road.

really what you are asking for is impossible. a 100mph speed runner on one hand and a daily backyard off road basher on the other?? aint gonna happen. even at the World RC Speed Record races where people dedicated to RC speed come from all over the world there are dozens that show up but you can count on one hand how many break 100mph. and that is in perfect conditions and a prefectly smooth drag strip.

but if i was going for 100mph what i mentioned above is how i would do it if i wanted to do it cheap and just try it. good luck!!

The biggest problem is the tires at least that the issue I am having. I know that any stock mt rubber with internal foam donut tire wont last past 80mph. So basically thats your brick wall. The carbon fiber thread is glued on the outside of the tire and duct tape on the inside on the hpi phaltlines.Heres a pic: These are pics of OverevO's 91,2 mph brushless revo tires.
http://i153.photobucket.com/albums/s...x/P1040292.jpg
These are good for at least 90mph. At 100 they might explode because it hasnt been done yet.

Brian Sigsworth has gone 105mph in a 1/8 OFNA GT2

http://fastestrc.blogspot.com/search.../1%2F8%20scale

http://1.bp.blogspot.com/_3N0hwXEVK9...nap-309426.png

Joe Ford has gone very fast in his Inferno GT2

http://fastestrc.blogspot.com/search/label/joe%20ford

http://1.bp.blogspot.com/_3N0hwXEVK9...16_vMedium.jpg

This was Joe's goal:

This is what Joe said about his setup:

I have gone 83 mph in an OFNA GT2 with a Neu 2215 on 8s. (but that is a very expensive setup). http://fastrc.blogspot.com/2008/06/t...ay-83-mph.html

I would go with:

OFNA GT2 - $190 (http://www3.towerhobbies.com/cgi-bin...?&I=LXTCJ1&P=7)
RC Monster Motor mount
Castle Creations 2200kv/Mamba Monster combo - $300 (http://www3.towerhobbies.com/cgi-bin...&I=LXVHA5&P=ML)
Thunder Power 6s 30c li-po ~ $225 (http://www.rctoys.com/rc-products-ca...BATTERIES.html)
Large pinion (22t+)

Thats fast but that car in the isc event would be put in open class which it wouldnt have a chance doing those speeds. Currently 161mph is the record. I personally think a open wheeled revo doing 91 is more impressive then an on road car doing 105.Two different classes anyway so it doesnt matter.

I have seen this car in person and have personally seen it run. Its amazing actually! He's doing it on a fat 4s MaxCramps pack, 1515 motor, and a huge pinion. Not a bad setup! Looks great as well!

I've used 1400kv, 2000kv, 2700kv, 3000kv and 4000kv in a GTP and all are fast setups. The 4000kv setup is the easiest to learn how to handle high speeds in a 1/8 car within 250 feet of space. This space includes braking distance.

so glueing fishing wire around the tire helps with ballooning?

just out of curiosity, what if i hooked up a 3s 5000 and a 4s 5000 both 30c in series for a total of 25.9 volts, now the castle creations esc is rated for 25 volts could it handle the extra .9 volts. would it do some serious damage or just get really really really hot and would have to let it cool for like hours between each run? just curious

your forgetting that that is nominal voltage

when fully charged a 3s pack is 12.6 and 4s is 16.8

totalling 29.4

and thats not fishing line- its carbon fiber twine...

^ +1. Also, there is a TVS device in the MMM which is designed to help clamp the voltage (during braking) to something around 28v IIRC. So, 7s lipo will likely blow that device and it will no longer help prevent voltage spikes.

so basicly i want a low kv motor like the tekin 1350kv and then play with gearing right?

Personally for speed runs, I like to keep my motor at around 50-60Krpm under load. So a lower kv and/or longer motor with more voltage(higher efficiency) would be able to handle a bigger load(gearing) to reach your top speeds. I suggest you get a datalogger to help reach your goal and not blow up stuff in the process.

Goofing off I keep motor rmps at around 30k or so.

not if your main goal is to hit 100 MPH unless you have $400 for lipos and want a heavy car. a 10k kv motor and 3s will get you there but it not going on the road you spoke of. If this is a real goal going 100 mph on $900 with a 4x4 or a truck maybe 4x2 you can do it... My Idea

emaxx lowered to ground scraping, monster mikes FLM diffs, 2 castle monster systems, a wing and a prayer and dont touch the steering

Play around with the BrianG calculator and figure your optimum combination for the vehicle your going to use.

well it really is a goal of mine but playing with some figures on the rc calculations site, just doing different combos with the 8th scale motors even on 6s i don't see them getting me to my goal, i don't even think they make that high of a pinion on some of the calculations i did, lol. guess it was a fools goal i guess.

Lower the spur gear tooth count raise the diff ratio if you can or raise the kv then run 8 or 10s lots of way to hit your goal just cost more money. I think the neu 1.5d 2650kv is the optimum engine for 6s at 59400 rpm on 6s 60000 is pushing the limit. I believe 25 tooth is the biggest rcmonster sells but there are other alternatives.

were would i get a esc and motor that would handle an 8 or 10 lipo? well i found an esc that handles up to 10s theres one right here on rcmonster, but what about a motor that can handle that much power?

You can get one of the new phoenix ice or the phoenix HV110 and run up to 12s but will need an external bec (battery eliminator circuit, use mechanical brakes, and get a pistix adapter for your pistol grip radio to work.

what is a pistix adapter? cool never thought about using airplane esc do you know of a motor i could use to go witht that esc cause im sure the mamba monster won't handle 12s?

I'll take the leftover bits of whatever car you buy after you crash at 100mph...:whip:

driving that fast is a pain in the @$$ to keep it shiny side up and off of the curb...

your best bet is to get a HPI E-firstorm, drop in a MMM with a 9000kv on a 3s and have fun:yes:

FYI the motor "should" handle the RPM according to castle...

[QUOTE=whitrzac;314749]I'll take the leftover bits of whatever car you buy after you crash at 100mph...:whip:QUOTE]

haha very funny, :lol:

i didn't see whether the motor is only limited to 25 volts is it? can i use that with a 12s pack, or do i still need to find a motor that can and says it can?