Del Monte's Anti-IFS Wraith

[Del Monte]

Ok, not really anti-IFS, maybe I'm just a little jealous

After seeing JIA's killer IFS builds and the awesome work Skaldiddog is doing with his new Wraith, I thought it was time to step up my build. I believe that with proper shock tuning, a solid-axle Wraith could hold its own against the new breed of IFS trucks, both on the rocks and at speed.

My Wraith has seen rocks all over the country, experienced 400+ gate G6 events, and taken top honors at this year's Nationals Scale dash. It was primarily set up for Go-Fast driving, but my goal now is to build a dual-purpose truck that is capable on and off the rocks.

Specs:
Tekin RS Pro w/13.5 motor
2S 5000mah packs for G6
3S 1350mah packs for High Speed
43/13 Diff gears F/R
BLS157HV servo
4" shocks

Ride Height


Full Droop


Full Compression




The rear shocks are mounted on the lower links using the link/shock mounts from the XR10 kit. A lot of the Wraith cage had to be sacrificed to get the amount of compression I wanted, but it was worth it for the travel and stability the truck has now. I used an LCC shock arm to push the top of the shock forward to give me a better shock angle through travel. The shocks would start to cam backwards when mounted in the stock upper mount, and this was causing some funky issues on the rocks.

[dieselmudder]

this promises to be interesting.

[Del Monte]

I've been playing with MIP's new bypass pistons on to help this truck float through the rocks. Theoretically, these allow for tuning compression and rebound separately.



I had been running these in a short 3.5" shock with mixed results. Now that I've switched to a full 4" shock, I have enough travel for the bypass pistons to really work. For now, I have settled on stiffer valving and 30wt oil. The valving discs are stiff enough that when driving slow the shocks react slowly and feel like a normal crawler shock. Once the speed picks up, the valves flex and let oil flow by, allowing the suspension to react quickly. The setup isn't 100% dialed just yet, but I believe that it will be a big part in making this truck a solid dual-purpose rig.

[JasonInAugusta]

The rocks go UNDER the rig.

I've been playing with my wife's SA rig and shock tuning. Got the rear worked out and the front is nice, but it seems no matter what you do, that front 4-link will cause the rig to bounce around more than an IFS rig.


It'll take a lot of tuning to get it in the ball park of an IFS. A lot.

I'll be watching...and waiting for video.

EDIT, I used RPM's 2-stage pistons years ago. Raced a Stampede with Masher 2Ks in the 2.2 stadium truck class (yeah, against XXX-Ts) .

Got 3rd.

[Del Monte]

Originally Posted by JasonInAugusta

The rocks go UNDER the rig.

I've been playing with my wife's SA rig and shock tuning. Got the rear worked out and the front is nice, but it seems no matter what you do, that front 4-link will cause the rig to bounce around more than an IFS rig.


It'll take a lot of tuning to get it in the ball park of an IFS. A lot.

I'll be watching...and waiting for video.

I needed something heavy enough to hold the truck down for a pic, and the closest thing was an 801Rcc trophy. Worked perfectly

I definitely agree with you on the shock tuning. It will take a lot to get the truck to handle as well as an IFS build, but I think its possible to get close.

I remember seeing those pistons before. I believe Axial made some at one point too. The MIP's are the first ones I've played with that felt tune-able.

[JasonInAugusta]

Originally Posted by Del Monte

I needed something heavy enough to hold the truck down for a pic, and the closest thing was an 801Rcc trophy. Worked perfectly

I definitely agree with you on the shock tuning. It will take a lot to get the truck to handle as well as an IFS build, but I think its possible to get close.

I remember seeing those pistons before. I believe Axial made some at one point too. The MIP's are the first ones I've played with that felt tune-able.

If it takes more than six hours to sort out, you might as well just let me do an IFS conversion.

Anyway...

You probably already know this but...

The problem you're going to have is the physics behind how that front SA works with the 4-link. It has to hit and swing in an upward arc. That transfers forces through the entire rig through the 4-link. If your axle centerline is below level with the pivot point of the links at the skid you'll get more of a jolt to the entire rig than you would if your centerline and chassis pivot point were on the same plane.

With the IFS the tires move up and back on impact, absorbing the energy instead of transferring it through the links.

[Del Monte]

Originally Posted by JasonInAugusta

If it takes more than six hours to sort out, you might as well just let me do an IFS conversion.

What's the fun in that?

Actually, I would love to send a truck over for the conversion once the budget allows. If nothing else, this truck will be a perfect to test out some shock tuning ideas before moving on to an IFS build.

[JasonInAugusta]

Originally Posted by Del Monte

What's the fun in that?

Actually, I would love to send a truck over for the conversion once the budget allows. If nothing else, this truck will be a perfect to test out some shock tuning ideas before moving on to an IFS build.

According to all the guys that have them, and have driven them...

Is
Fun
Sh*t

[special agent]

It sure is

I - IT'S
F - FUN
S - SH*T

its handle way better than a SA truck. it crawls at low speed, hammer down thats where the fun begins

[SkaldidDog]

Yeah baby! Look forward to seeing it in action.

J

[Steelfish]

sub'ed

[Frankenwheely]

Me Likey.

[binaryterror]

Definitely going to watch that. That is the goal of mine, but having raced for years I want good handling. Maybe its impossible to beat the IFS guys at that side, but I still like the challenge.

Might go to the Exo back cage for looks and the longer shocks to play with travel and limiters.

[Del Monte]

Added a hinged hood using some 1/4" cable clamps from Skaldiddog.



Now its easy to swap between crawler and go-fast ESC settings.

I also settled on 19/80 gearing with the 13.5 motor. The truck has plenty of speed, even on 2s, but its much more controllable on the rocks now.

...and

Here's a quick video from the last test run.

from Jake Wright on Vimeo.

The truck is working great now with the 4" shocks. After watching some of the video in slow-mo, it looks like it might need thicker oil to slow down the rebound a little.

[dustin_mud]

Looks like it preformed really good, keep it up.

[Frankenwheely]

@ :36...Nice.

[SkaldidDog]

While operating your radio with one hand...

[JasonInAugusta]

:53-:55 is nice!

[benmara]

updates?

[Soulo747]

I have an SA rig and love it, but as Jason pointed out its all physics. IFS = force isolation. There's a reason KOH is now being won by IFS rigs. Rock performance is comparable to SA, at speed the IFS shines.

Looking forward to the build!