Budget rock bouncer/bashing wraith build. Some tips welcomed!

[mckhus]

Heya
I’m working on my light Basher/rock bouncer wraith build and could use couple tips. My goal is to lower ride height without sacrificing much suspension travel, lower the cg a bit and give it slightly meaner look. So far ive installed stronger faster servo, added 120 mm soft shocks with extra shock mount plates which extend the mounts about an inch higher, flipped the link/shock mounts to extend the wheel base and lower it just a tiny bit more. Battery relocated to front, electronics into interior leg space. I’m not scared of hot glue and cutting some pieces to shape, zip ties are my best friend and with this build function over looks.

Ive cut the back off and made some extra support braces using plastic from rear and to my surprise its super sturdy. I got some plans to shorten the pipes even more.

Been running it on and off on 2 and 3s with stock electronics, quite happy with 3s speed and bashing but I’m swapping to sensored brushless motor. 17,5t 2200kv, i guess i will need to gear it down to about 6:1 ratio to keep the performance similar? Any budget friendly recommendations?

Currently the suspension is setup so that it bottoms out when top links hit the cage parts, i believe there is still an inch of travel to be squeezed out of the setup with some cutting. Maybe it wont even be necessary if i were to swap top links for less-bent ones. I have been thinking of cutting the bottom pipe that connects cage to chassis plate and drilling new holes in upper pipe, that would lower the whole cage down

Has anyone done that?

Oh lastly i run pretty compact 2200 mah 3s lipos, i could probably fabricate some better battery mount than forward mod one, possibly in line with vehicle not across it.

My long time goal is to add rear steering, probs will need a bec for that. I want to keep as much as possible plastic so it bends before it breaks. The metal in axle tubes and steering knuckles are probs only solid things i want to have on this build.


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[Steve g]

Moving the skid up like that is called a tummy tuck. Many have done it. I almost did, luckily i mocked it up before cutting anything. I noticed it limits the up travel of the axles, and its really only lowering a very small weight down. I'm sure some here may argue its worth it, but not me.
Try some lighter springs so it sits lower in a static position. The front shocks look like they are on the forward most position, you want them in the rear hole, it'll lower it some there.
A 17.5 brushless 2 pole motor isn't going to spin too much faster then the stock 20t brushed motor, so gearing down alot will drastically cut your top speed. Would be good for crawling though, but it seems you are more after rock racing. I tried a 17.5, not much difference in performance over a 21t 550 i had before it. I do run a 13.5 in my sons wraith, geared something like 17/87 i think, and it crawls well, and has a top speed of about 10 mph on 3s. I have the castle 3800kv 1410 in mine, geared lower, but is both faster and has more low grunt then the 13.5. I would recommend 3000 to 3500kv, like the puller pro, if its within your budget. If not, get a 10.5t motor, to get more wheel speed and torque versus the 17.5.
Now those stock links won't last long, I got maybe a month out of the plastic hollow balls before they were just wiped out. Wiped out the hot racing aluminum ones in a few months, along with the links themselves. Traxxas summit/erevo pushrods are a direct swap for the lower links, can get those cheap and have replaceable revo rod ends with steel hollow balls on them. Also adds a little weight down low.


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[mckhus]

Tummy tuck, guess i will look for some guides, thanks! I think its more for mean stance as indeed most of heavy parts are already quite low and bolted to skid plate.

The 17,5 is on its way in post already, I will see how it performs and think of new gearing in that case. Still got a giant heavy 2s hardcase lipo that might just fit my needs then considering its less speed than 3s.

The shocks are already with double soft spring and ive set them this way so they bottom out right as links are about to hit the plastics. I’d say they are at about 30% compression in resting state. If I’m gona do the tummy tuck then cutting some extra space for links is not an issue. Some hot glue and screws will help creating new support like i did in rear and it holds up well.
Eventually i will remove all lexan pieces and form some sort of tighter roll cage.

So replacing links will be a must. Maybe i can get by with just top ones for the time being. Do you have any experience with sway bars for wraith? With soft springs in back i do experience some throttle twist. I’d have to create custom mount to the cage and probs change shock mounts on axle as there is no space to bolt extra link to.

On a side note right now as it is, it crawls like crazy, if you can even call it crawl. Storming up some stone stairs in the woods, steep hills.


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[Steve g]

I run my shocks a good 60% compressed at rest. Keeping the truck low will help both crawling, and the higher speed handling. I like to do some crazy hill climbs, aswell as technical crawling, and having the lower ride height has been one of the most beneficial changes I've made.
I also run a sway bar on the rear of mine, but haven't put one on my son's. I'm running short lenght trailing arms in the rear, which increases rear axle travel, and softens the shocks. So lots of torque twist without the sway bar. I do recommend it, corners better at higher speeds, and also seems the crawl better, think i had too much flex with out it. I'm running the axial sway bar, medium torsion bar, with the longer arms that are for the front kit. ( i got both front and rear kits half off) The longer arms soften the anti sway movement some. Was running the softest torsion bar, but I broke both of them, along with 1 other medium one. Flying up steep ledge and tumbling back down tends to break them. Thinking of trying music wire one day, cheaper then the axial kits. You dont have to move your shocks, just get a longer bolt and bolt them on the inner side of the shock mount. (The kits include them, if you buy the kit).

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[mckhus]

Played around with shock positions and indeed backing the front a bit helped with handling. I feel like however that either my oil is too thin or i need limiting straps since durning bashing the suspension extends a bit too fast and it seems like shocks take a big hit during it. Whole axle weight pulling on them especially durning tumbles.

Problem is its a budget car, i got the wraith used in mint condition for 200£, adding a 40£ sway bar feels kinda wrong. I’m sure if i were to go for a nice dedicated build I’d get. There is some bomber Chinese sway bars on eBay for 7£, i will give this a go. I gotta fabricate a mount for it anyway since the original is cut off. I will probs remodel the cage during installation process.


Oh and i get what you mean with longer screw, saw that on other build, should work easy.


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[Steve g]

I saw those cheap sway bars, been tempted to get one for my son's wraith. Let me know how it works out.
Try thicker shock oil. I forget what I have, but it's thicker then stock. Ours are also mostly budget builds, been building mine up for over 3 years, which I got used, but totally stock. Got my son's wraith last year used, barely a scratch on it, but had nice upgrades already. Save up for a set of the updated front universal axle shafts, the stock ones don't last. And the lockers, I'm running locked-up rc ones. Stock ring and pinion gears will give out aswell. If and when you get new ones, get the under drive for the rear, and stock ratio for the front (seems any brand that are HD are good to use). It'll help with cornering, torque twist, and hill climbing. And keep a close eye on the pinion bearings, they wear out fast, and if you don't notice it in time, it will destroy the ring and pinion gears.

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