wareagle84

I ended up putting a little silicon in the rear diff to lock it up. if it causes problems I may try the lockers.

WaftyCrank

Thanks, that would be great.

ThePanda

iTrader: (68)

Ok so has anyone done this with the stock shocks? try filling the shocks from the bottom. So fill normally from the top, with bottom cartridge in place, then flip over, remove bottom eyelet and cartridge, and orings, and carefully feed oil into the bottom,pull the shaft out so the oil gets sucked in, then bleed and push out excess air. repeat several times, then, push shaft in all the way, replace orings, and add bottom cap.and pull out shaft. I did this, and i was able to build with much less air than i was ever able to do with bleeding them from the top. just the tiniest bit of air is not in the shocks, and they have a vacuum in them.

tswmcello

Intro;
Hey everyone, so I just recently acquired a sprint 2 flux with two 7cells, an extra rx, tons of extra parts, and three bodies (rx7, mustang, and honda odyssey) for $200 (I think that's a good deal?). Before I bought the sprint I read most of this thread and liking a good project (electrical engineering major at Case) I bought the sprint 2. I also have a completely upgraded slash 2wd that I raced once and may race again.

What I did;
First thing I did was move the waterproof electronics to my traxxas slash and take my sidewinder v1/ tekin 448 combo from the slash and put that in the sprint (I don't plan on taking the sprint through puddles..). The tekin 448 in the sprint runs like butter, the original vector was very torquey and jittery... something I don't mind in bashing my slash around in puddles and general messing around. I also have a 3s 6400 maH 20c, 2s 4000 maH 30c, 3000 maH 7 cell, 3300 maH 7 cell, and a 5 year old (still cranking) 4600 maH 6 cell.

What I would like to do;
I would like to race my sprint 2 this summer on a local asphalt track in the open 1/10 touring class, it has one straightway and a lot of turns. I have heard about grippers and drifters...and I like gripping but also a little slide for tights turns.

Sprint 2 Current electronics:
2s lipo, 6 cell NiMh
Flysky rx
Tekin 448 sensor less brushless 4800kV
Sidewinder v1 (still runs like a champ)
Stock servo

So far:
Upgraded to all RPM 4-40 ends (purple)
Ordered Exotek CF chassis
23T 48P traxxas pinion (I have no idea if P is right but it works fine and haven't had any stripping)

What I plan on doing:
Install Exotech chassis
Battery Bracket cutting
Spring Mod for bones (will be sad to see a pilot pen wasted..)
Front belt lifter (need bearings)
shim stupid left crank (I can't believe how much it moves!)
Maybe CVD's ($$..)
Rear belt tensioner
shims, shims..
50wt oil in shocks
kevlar belts

Questions;
Is it more worth it to shim the hell out of the stock steering, or drop $30 on a sprint 1 steering set? What setup would you guys recommend for asphalt on a technical track in summer heat? My stock servo sucks, its dying and returns very slowly, what servo would you recommend? Are there any other mods that are vital to do well in a race? Gearing recommendations?

I don't need every lap to be exactly the same or steering to be 100% perfect... I like the excitement of change and quick decisions and don't mind crashing every once in a while to learn a lesson.I will try to get a video of me racing my slash form a couple years ago so you guys can see the track.

BTW, Marv your mods and advice are amazing, I have never seen a thread with such detailed mod descriptions. As well as advice from everyone else on this thread.. very committed following for the sprint 2!

WaftyCrank

I think the general opinion is the sprint 1 steering is the best solution. I used a combination of rs4 steering set and the sprint 1 set to fix mine (you can see it in post 677) this does not remove all the slop, but with the addition of a spring or a rubberband between the steering arms you will reduce most of it.

As for the servo, I opted for the Savox 1258tg. Its quite noisy and some people report brownout issues with them, but I have had none so far, and I think its something to do with tx/rx people use, but as it hasn't been a problem for me, I haven't looked into it too far. Alternatively, you can buy a BEC as Marv did early on in the thread.

As for any other mods, I think you have most of them covered. The Kevlar belts from tough racing are a must, and the rpm ends are too. I felt the car was a bit tail heavy as stock, so I shifted my lipo more centrally and it feels better imo. I also ditched my waterproof rx case and put the rx between my servo and belt on the bottom deck, but that was just my preference.
Oh and as a last comment, Marvs idea for the pen springs between the dogbones is a good un, much better than the o-rings.

tswmcello

Thanks for the response, I am actually trying to get a 1258 right now (one on sale for $45 shipped on here). Also, I am likely going to make my own glitch buster, I am a EE at Case and I can grab any type of capacitor imaginable. And to clarify, do you think the sprint 1 set is worth $30? I am going to be racing and being pretty competitive usually I'd like to do somewhat well. Can't wait for that exotech chassis to arrive!

WaftyCrank

When I bought the s1 steering set HPI-86005 its was £12 and in reality it was the mainly the stand off I wanted it for, and some of the shims.
I added the parts from this set... http://www.asiatees.com/display?HPI-...4%203&id=44106 which had the right bearings to match the alloy gpm parts I already had as well as the stock parts I have on my second s2. Below is a picture of it the oem parts. I went overkill on the bearings but I wanted the height right...

However, a mate of mine was able to use just the rs4 set with the standoff inverted and it worked out well too, although I do recall him saying he had to shorten the larger shims to make it butt up against his top deck nicely, but it wasn't a major mod. I will ask him to send me a photo of it to show you as it will save you 20 dollars =)

edit.... Added the pictures of my friends set up using JUST the rs4 parts. As you can see he has chopped into his topdeck to accommodate the larger stand offs and shaved the lower shim shorter. I added pics of OEM and with the alloy parts too.

tswmcello

Wow thats a nice price right there on the rs4 steering setup. However, do you think there would be any way to use it with the Exotek chassis? I mean I could always use the stock upper deck, but the carbon fiber just looks so nice..

WaftyCrank

I can't see why it wouldn't work with the bottom deck of the Exotek chassis, especially if you use the stock top deck to support the top of the stand offs. However, if you really wanted to use cf top deck too, you could perhaps fashion a brace to bridge the two steering arms but its not something I have had to try on anything but my micros. As long as it is clear of your belt, it should work.

For the price of the rs4 set, its worth picking one up and tinkering with it till you find something that works for you. Post some pics when your done =)

bo duke

iTrader: (1)

just found this thread and cant wait to mod my sprint 2!

bo duke

iTrader: (1)

I was looking at replacement parts for this car and it seems a lot are discontinued.

wareagle84

that depends on which ones you're looking for. if you're looking for the purple anodized aluminum pieces or the graphite/carbon fiber pieces, then yes, you're correct.
if you're looking for stock plastic parts or electronics or the orange anodized pieces, they're not discontinued, just out of stock/backordered until HPI makes more. BTW, you could build a Sprint 2 completely from scratch by looking on eBay for less than 2 minutes. Tons of stock replacement parts on eBay right now.

bo duke

iTrader: (1)

the steering servo saver was the big thing I seen on tower hobbies that was discontinued that I thought was crazy.

IamSand

Hey guys, thanks to all those that contributed to this thread. I've been playing around with my Sprint 2 for a few months now. So far I've done a front motor conversion, 2S lipo, SW3 w/4600kv motor with a 75T spur, 37T pinion. I've got the timing set to 0*. Also a Fubuta romote and receiver. I've got a quick video of it ballooning the tires, but no videos of any runs yet. Here's the vid, let me know what you think.
http://www.youtube.com/watch?v=VCJqG...e_gdata_player

SeeGee911

iTrader: (1)

Can the sidewinder 3 handle a 2.02 gear ratio? Even at the lower kv I'd suggest that you monitor your temps closely when actually running that thing under load. I'd hate for you to burn out your esc. That's never fun. Do you have any method of actually clocking the speed you get? I'm curious to see how it performs, keep us posted!