jedi.mind.trick

Hi everyone!
Need some help with purchasing my first kit..
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[history - unnecessary to read ]

my first RC was a RTR HPI RS4 evo3 (1/10 onroad) and my second was a GV XT2 RTR (1/8 off road) since I bought the off road I had gone away from the hobby and now I have recently rejoined and want to get something new and more capable, I was tossing up between a 1/8 truggy or a hpi baja but i think I will go with the truggy for now and I might get a baja further down the road.
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I have pretty much made a decision on the Losi 8ight-T 3.0, I know it's pricey for a non serious racer but I'd want something that was capable if I did end up on the track.
I was originally looking at the HB D8T for both the price and good reviews but there's something about the body that turns me off(the front end)..even the aftermarket ones don't add much to the aesthetics of this truggy, which is a shame..

I have an Airtronics MT-4S radio and have been looking at Savox servos (still haven't made a definitive decision on which though) 1258TG,1256TG,1231SG etc...1233SG looks the business, but being a tall servo would it be suitable for the 8T?

I haven't even started on the engine.

So i guess I'm looking for a little guidance, opinions, options, tips etc.. Any help would be greatly appreciated..seems all so overwhelming especially when you're someone who tends to read too much into everything..

Also, is there anything I need when building kits that wont come with it? like any tools(apart from the obvious hex drivers), greases, oils etc?

Thanks a lot

p.s my apologies if i posted in the wrong place.

Marciatelli

Sup man,

Well, you cant go wrong with the Losi, I personally havent got it but it receives a lot of good reviews and overall seem to perform like a beast. People love to bash with it and love to race with it too. Good choice in the truggy.

Servo talk :
The servos youre looking for are standard size servos, something around 40mm long x 20mm wide x 40mm tall.
Since you will be operating a nitro engine, I guess you will be using a hump back ni-mh receiver battery that is 6V.
For the steering servo you need something that will pull out around or more than 200 oz/in (~14kg/cm) and less than .12 sec/60degree at 6V and metal gears.
For thr throttle servo you need something that will pull out around 140 oz/in (~10kg/cm) and something with less than .12 sec/60degree at 6V.
There is no point going more with torque on the throttle servo because it is simply an overkill.
I have stated what the minimal requirements would be for steering and throttle servo, but the faster the better, just look around if you can find .10se/60degree at 6V.

Engine talk :
I am not sure what the rules and regulations are when it comes to truggy racing, you should check the rules depending where you gonna race, Im sure they will provide the info.
Well, depending on what your restrictions are, since its 1/8 Truggy .21 or .28 big block engines can be used. Anything with RPM range of 6k - 36k would do.
Just remember that they have to have 14mm SG crank shaft.
Here is a list of possible engines you could use in your project, all of them are good bashers, some better than other (check racing regulations of your hobby track before purchase):
- Dynamite .21
- Werk B5 .21
- Novarossi P5 .21
- Trackstar SEG .21
- Picco .28
- LRP .28

People are very opinionated when it comes to research so look out and do your research, there is plenty of motors that can be used and are good to do the job and their price range is very wide.

Building wise you need patience, tools and love haha. Honestly, I havent built the Losi 8ight T so I will let more competent people talk.

Mark

Maj_Overdrive

My Feedback: (11)

Marciatelli's advice and points are very sound.

For servos his recommendations on the torque specs are right on. In my opinion though .12/sec is pretty darn fast, as long as you have enough torque to go along with it you don't really need to go faster on the steering servo. Just my opinion. Also servos get pricey when you want faster than .12/sec combined with 200oz or more of torque. The throttle/brake servo on the other hand should be faster though as you'll notice it more, here I'd definitely go for something around .10/sec if you can.

I also like like his engine recommendations, specifically not going right for a .28 engine. A smaller .21 does give up some power but unless it's a really big track where you can gear for more top speed you won't really notice it much. The .28 may be too much to power out of low speed turns without spinning the tires. They also don't rev as high due to the long stroke and their fuel mileage is worse. There are some in between .24 and .25 racing engines if you're doubtful about which way to go.

I have an 8ight-t 2.0 and love it. I completely understand buying more and better than you may need, it's your coin to spend and if you're happy with it why not. I haven't tried them yet but the Losi can obviously take a Smart Diff which are supposed to be really good on a track as well. Personally the only other high end truggy I'd consider is a Mugen, they have a well deserved reputation for being built like tanks and proven on track performance as well.

The only build tip I have is to take your time. The better built it is the less headaches you will have. You'll want to pay particular attention to the shimming of the rear diff. It was a bit of a trouble spot on earlier versions but Losi did make some improvements in this area.

jedi.mind.trick

interesting, thanks for the replies!

I read somewhere that as long as the steering servo had at least 140oz+ and .18 and under .. 120oz+ for the throttle..
I've been looking at the Savox 1258 for throttle and the 1256 for steering (or even just 2 x 1256's)..the specs are: [1258 - 166oz/.08 @ 6v] [1256 - 277oz/.15 @ 6v]

Also been looking at the Werks B5, out of the 2 pipes for it (2058 & 2013) which one would be the better option? like what's the pro's & con's for each?

Maj_Overdrive

My Feedback: (11)

I personally like overkill on my servos, so I agreed with Marciatelli. I run a Hitec with 333oz on my 8ight-t but that's mostly because I know and like that particular servo. You could get away with 140-150oz on the steering but around 200oz ensures you have more than enough capability. As for speed .18 is slow, even for bashing I won't run slower than .14-.15/sec. For throttle/brake 120-150oz is where you want to be and you notice the speed of the servo more here so as fast as you can afford is what to get.

The Savox servos you've picked have good specs, that 1258 would be awesome on throttle/brake, I don't think you can go wrong with those specs. I haven't run Savox but they are known for being power hungry little buggers. If those servos and your Rx are capable of being run directly off a Lipo I'd run one instead of a NiMh Rx pack to maximize run time.

jedi.mind.trick

I know the Rx can take a LiPo..not sure about those servo's, i doubt it... i thought only high voltage servos could take LiPos?..someone in another forum mentioned he runs these off a life pack and they can handle the extra .6v would a LiFe make much difference over a NiMH?

Marciatelli

I agree with Maj_Overdrive, Savox 1258 would be the way to go for throttle!
I could suggest Savox SC-1268MG if you want to have both servos from them same company. 1268 has .13sec/60degree 15kg/cm (~208oz/in) at 6.0V. .13sec is alright for driving, not too fast, not too slow, just fine.

I am a twichy driver myself and for me .10 and .12 sec/60degree is like heaven and... not hell but you get the idea. Going beyond .14 becomes sluggish and kills the fun, and if you go super slow then you have to start turning before the turn to compensate the sluggishness. In my opinion it aint fun.

From my experience the more powerfull the servo (high speed with high torque) the more power hungry it is. 1500 mah NiMH is more than enough for few hours of runnig before charging again. Running 2s lipo for receiver is around 7.4V (3.7V per cell) but fully charged it will be 8.4V (4.2V per cell). If you dont have a high voltage operating rx and servos, the circut is gonna light on fire faster than christmas tree with candles on it.
If your rx can operate with high voltage (2s lipo) but your servos cant, you can play around with BEC's (Battery Ellimination Circuit) that are designed for the job (you have to research servo bec's). BEC is really usefull for using LiPO and just messing around making it compatable.
Yes, LiPO is much more powerful with more power capacity compared to NiMH, and it has much more constant voltage. Other than that LiPO needs a specific charger for it, its easy to deal permanent damage it if the voltage drops too low (lower than 3.7V static per cell) and its more feasible to catch fire when case is damaged/puncture. Is it worth to get a 2s then? Its your call. I like my NiMH to drop voltage, have a normal charger and overall being "I dont give a f*ck" battery.

Werk 5B is a good choice, grab some 25% Byron and it gonna scream! Quite easy to tune too.
Which pipe? I used to run my 5B with 2013 and its good, you dont need anything else. I would go with 2013.
I am not a specialist but this is what I know on the topic.
Both pipes are low-end tuned, and are pretty much similar (not the same tho) in nature.
The difference between 2013 and 2058 is that 2058 is a racing replacement for 2013. iFMAR (international Federation of Model Auto Racing) has banned 2013 pipe around 2010/2011 (I dont quite remember when) because its too loud (I approve haha). Compared to 2013, the 2058 is quiter but because of that it is slightly less efficient with the fuel.
So real talk now. If you bash, go with 2013, its loud, has a nice rpm low range, its slightly less restrictive and enjoy the sound.
If you race go with 2058, its quiter and race aproved.

Mark.