2wd Slash: Way To Squirrelly

[macanic21]

I'm just getting my feet wet with this 2wd slash with a 2.5r. My problem is that it is nearly impossible to drive. With any kind of throttle input at any speed the thing spins out immediately.

Current Setup: 0 front toe, front suspension is Integy aluminum stuff. Rear is toed in with factory non-adjustable setup.

Any suggestions on what I should work on? I'm going to try more front toe-in but for as bad as this is I can't imagine that will help much.

 

[cbaker65]

I'm just getting my feet wet with this 2wd slash with a 2.5r. My problem is that it is nearly impossible to drive. With any kind of throttle input at any speed the thing spins out immediately.

Current Setup: 0 front toe, front suspension is Integy aluminum stuff. Rear is toed in with factory non-adjustable setup.

Any suggestions on what I should work on? I'm going to try more front toe-in but for as bad as this is I can't imagine that will help much.

I don't think none of that is going to help!

Maybe try a different thickness of transmission grease ,or if it has a slipper clutch ,back it off a little!...

 

[macanic21]

Unfortunately it doesn't have a sealed diff... I was thinking of upgrading it to a sealed unit anyway. Would you suggest thicker or thinner diff fluid?

 

[macanic21]

My brother was nice enough to get me a sealed diff for Christmas. Unfortunately, I didn't realize that it was for the electric model only. Do you guys know of a solution for the nitro trans? I'm hoping to here back from Hot Racing about it.

 

[olds97_lss]

Not sure the diff will matter as much as throttle control, adding a bit of toe in on your front, softening up the shocks... my jato was a nightmare to drive when I had stiff springs on it.

Also, depending on the surface your driving on, you may need softer tires or a more aggressive tread.

 

[macanic21]

Thanks for the help so far guys.
I put a set of Trencher X's on the rear and wow, what a difference. It now goes better than my Slayer which has worn our tires. As with anything with tires, they are always the biggest bang for the buck performance modification. It will drag the rear bumper now when you get it hooked up! At this point I'm assuming it is as stable in a straight line as its going to get. The only other possibility for adjustment I have is the rear camber. I have this setup just slightly negative with the pick up point all the way inboard and down to reduce positive camber gain produced by body roll. I'll get a picture to see if you guys think I should try changing it.

The next complaint I have always had with this thing is the stock shock setup. These things are a horrendous disappointment from the factory.

Rear Shocks
So far I've played with about every shock pick up point that there is in the rear to try to get the stock rear shocks to support the weight of the truck. I have the most spacers in the springs before the coils bind at full compression. Frankly I think they are still way to soft but I got it to a point where I can jump it and it handles bumps as well as I think it can with the current equipment I have.

Front Shocks
In the front it was happy with very few spacers on the springs and a soft setup.
The problem is that now with the rear up high enough to have the travel it needs to absorb bumps and jumps, the truck wants to flip over in turns very easily. I stiffened up the front up which helped but I think at this point I need to go to sway bars. I'm thinking of trying a front bar first. I don't really want to use a rear bar which will reduce traction on the inner wheel, exacerbating the already to loose diff. The other option is to try a better set of shocks.

After market Shocks
So, I busted the mounting ear off a front shock this weekend when I caught a rut at speed. Now the question is, what shock set should I go with? The only ones I've looked into yet are the Proline powerstrokes. I'm not interested in anything that doesn't have a 2 spring progressive setup. What other options do I have?

Shock Oil
One thing that I haven't played with yet is shock oil weights. The problem here is that I don't know where to start. I have a bottle of Traxxas oil but there is no weight marked on it. What are your suggestions for running over rough ground and small jumps?

 

[olds97_lss]

I run a set of duratrax hatchets on my e-jato now. Awful awful foams that flattened out after just a few short packs, but the tires held up ok as did the rims. I refoamed the rears with some spare foam I had laying around.

I found when I ran springs/oil that could handle a 5 foot drop without slapping too hard, that it was way to sketchy to drive on dirt. I had to soften things up considerably and try to find a happy medium while avoiding airing it out like my savage. lol

I'm running an old set of revo shocks on it which came with 40 weight stock, I think, but I'm running jato springs with associated 50 or 60w oil now, green springs on the front, red on the rear. Seems to do pretty well.

On my stampede 4x4, I'm running stock shocks with 80 weight and integy t-maxx green springs... because I had them laying around. My next option with that rig is figuring out the 1/8th scale shock setup, but that's not cheap, so not sure where I'll go next. It does pretty well though with 2.8" trenchers on it.

 

[macanic21]

Here are some pictures.

 

[cbaker65]

Here are some pictures.

You sure do have a lot of spacers on the shocks ,it looks like your trying to use them to raise the chassy
for better ground clearance which will alter the way the truck handles ,making the shocks too stiff can
cause the squirelyness!

 

[macanic21]

Yeah.
Even with those spacers as soon as I turn the outer shock compresses almost fully because it is still so soft. This is causing the truck to flip very easily. Also, if I soften them up more it bottoms out over bumps so hard it flips forward. I guess I could try thicker shock fluid but I'm getting powerstrokes to match the front and putting 50wt in the rear.

One thing makes me curious. Why is the factory powerstroke spings setup softer in the rear?? There is much more weight on the rear so why is this how they do it?

 

[cbaker65]

Yeah.
Even with those spacers as soon as I turn the outer shock compresses almost fully because it is still so soft. This is causing the truck to flip very easily. Also, if I soften them up more it bottoms out over bumps so hard it flips forward. I guess I could try thicker shock fluid but I'm getting powerstrokes to match the front and putting 50wt in the rear.

One thing makes me curious. Why is the factory powerstroke spings setup softer in the rear?? There is much more weight on the rear so why is this how they do it?

I really don't know ,I don't own a short coarse truck ,I would think that you would want a softer
suspension but have enough ride height to keep from bottoming out ,so maybe you need a
taller shock to compensate for the ride height an not compromise the suspension!

I know when I want a higher ride height in my truck an it stiffens my suspension ,it causes my
truck to be squirely on take off!...

 

[olds97_lss]

Softer in the rear would give you better forward bite. Allows the weight to transition to the rear. Considering the width of the tires and power of the rig, you would want a lot of weight transfer to the rear when accelerating or it will just spin the tires... as your kind of finding out.

That said, it is a bit different than every other rig I've ever owned. Pretty sure every single one of them had either the same or stiffer in the rear. Then again, I've never owned a short course truck. Well, I don't remember them all, but most were nitro and the weight bias was to the rear. Only now am I getting into electric which seem to center the weight a bit better, so I tend to run the same springs in the rear as the front... no, I still run stiffer in the rear. However, I have the savage flux hp, revo brushless, stampede and a converted jato. Only on the stampede do I run the same springs on all 4 corners. Tried to on my flux, but was shipped stiffer than I ordered for a pair and I put them on the rear. Granted, every one of my e-rigs is also pretty heavily weight biased to the rear due to the motor placement, except the stampede.

Kind of jabbered myself in a circle there...

 

[cbaker65]

Softer in the rear would give you better forward bite. Allows the weight to transition to the rear. Considering the width of the tires and power of the rig, you would want a lot of weight transfer to the rear when accelerating or it will just spin the tires... as your kind of finding out.

That said, it is a bit different than every other rig I've ever owned. Pretty sure every single one of them had either the same or stiffer in the rear. Then again, I've never owned a short course truck. Well, I don't remember them all, but most were nitro and the weight bias was to the rear. Only now am I getting into electric which seem to center the weight a bit better, so I tend to run the same springs in the rear as the front... no, I still run stiffer in the rear. However, I have the savage flux hp, revo brushless, stampede and a converted jato. Only on the stampede do I run the same springs on all 4 corners. Tried to on my flux, but was shipped stiffer than I ordered for a pair and I put them on the rear. Granted, every one of my e-rigs is also pretty heavily weight biased to the rear due to the motor placement, except the stampede.

Kind of jabbered myself in a circle there...

LOL....WE are bashers!....

 

[macanic21]

Yeah, all I do is bash also. Thanks for the help guys.
I'm supposed to be notified when the rear Powerstrokes come in so we will see how those work. I'm planning on running 50wt in the rear so we'll see how that goes. Honestly, I think at this point most of the biggest issue with the truck now (which is the excessive body roll causing it to flip easily) could be solved with a sway bar. The problem with sway bars is that they actually pick up on the inside tire which will reduce my forward bite in the turns.

I'll see how the powerstrokes are and maybe buy a spring kit to rune them up with, then go from there. I also am going to gear this thing down so it is more usable at the speeds I can achieve where I run it.

I have also been playing around with my slayer which is 10x the truck this slash will ever be. I can't wait to get tires on that thing!

You know the other thing I'm wondering. If the guy who built this thing used electric shocks! I'm pretty sure he used the wrong steering and suspension link components because when I got replacement ones for a nitro, they were twice as beefy. I'll get you some pictures.

 

[macanic21]

 

[macanic21]

 

[macanic21]

So the previous owner had a gear set in this thing that wasn't even supposed to be an option. Thats probably the engine was spaced up with glow plug washers to make the gears mesh. The ratio worked out to like 2.6/1. I got the gear set they had in stock and it is now at 3.1/1. Hopefully it will be more snappy down low. With the other gears I was never able to even get it to top speed it was so fast.

I also got the rear powerstrokes on. I filled them with 50wt. I haven't run it yet but if I had to say anything I would say the oil might be a little thick and the springs might be a little soft.

Do you guys know how the small springs should set with the chassis at rest? Should they be fully compressed or not?

I would assume you wouldn't want them fully compressed so you get some suspension compression before it stiffens up.

 

[olds97_lss]

Would have to assume they shouldn't be fully compressed. Looks like the short spring is the softer of the two, so those would soak up the small bobbles down a straight while the longer springs absorb the jumps.

 

[macanic21]

 

[macanic21]

So, ^ that happened. Thankfully the new shocks didn't get damaged.
My brother is really good at breaking this thing. He did say it was much better and jumped really well. I should have just watched it run instead of running the slayer.
Now, on to Integy rear arms to match the front, as well as Traxxas mounting plates. The stock plastic ones were stripped out by the previous owner and the holes in the chassis were getting ovaled out from them shifting back and forth. I also got some anti-squat shims to play with. I started with the 1.5* ones. Apparently these can have a negative effect on straight line rear traction because they reduce weight transfer and effectively stiffen the spring rate. I might not need any anti-squat with these shocks but they were only a few $ to add to the order and will be fun to play with.
Also, both pins at the chassis through the arms were bent. I could barely get them apart.
Oh yeah, and another of the wrong camber links broke. I bought all 4 new ones which are actually correct. You can see I had to put a spacer on the inner rear one so it didn't hit the bulkhead. I don't know why traxxas built it this way unless the bulkhead is wrong. I'm sure spacing out this link will cause it to hit the shock so I might end up just trimming the bulkhead down. We will see when the arms get here.