Four Wheel Steering BL Savage XL on 8S & 1521

[Finnster]

I completed my mod for 4WS in my SavageXL. So far the list of goodies:

LST Shocks/RC Raven Progressive Springs
FLM Towers, Servo Plate, 2x drag link, servo mounts, lots of 4mm chassis braces, and eventually a skid plate
Neu 1521/1.5Y -1050kv
Kershaw Designs motor mount
MGM 9032 on 8S lipo
Custom oversized batt trays
2X 300oz Servos
40 series Mashers on 17mm Axial rims
Racers Edge Alu str blocks ($10/pr scored off ebay :) )
and of course a 45V UBEC

Basically I mounted a servo saver in the rear, as the F&R of the Sav is modular, so all the most of the necc holes already exist.
The rest of the mod involves cutting out part of the R chassis to clear the str rack:



Having to remove so much material, I reinforced the chassis with a cut up F shock tower from a GS truggy. I mounted this on the outside, but it would fit inside I just like how it looks. :) Plus it was only $1.50 on Amains clearance sale.



From there I mounted the servo to the inside of the TVP, and used a FLM 4mm chassis brace on for the top mount of the servo saver. There are a number of ways to do this. I finally decided on a method that left the servo up a bit higher and let the turnbuckle come down at an angle as a compromise of mounting ease, underside protection and rigid mounting. 2mm spacers were needed between the SS and the top brace, as well as some spacers for the servo mounts to clear some screwheads for the batt tray mounts.



Lastly I mounted the ESC aside the servo and mounted up the motor. The 1521 uses M4 mounting bolts, so I had to enlarge all the holes in the KD mount. I only did the L side to test, but I may do the R and move the motor above the ESC. I want to see how the ESC does with airflow first.



Underneath all this is where I will mount the FLM skid. I dont want a rock or stick coming up thru and striking the servo or the esc. The std skid plate should be about right, but may need some trimming. I also added 5x60mm turnbuckles from a hellfire, as well as the rod ends. Much tougher and tighter than the soft and sloppy stockers.

4WS was accomplished by using the 3Ch on my futaba Fasst radio and using the programmable mixing funct to tie to str channel. A trigger switch was programmed to switch between 2ws & 4ws on the fly.

So far I like it a lot (as you can see by the dirtiness of the truck ;) .) I tested the truck out and it ran great. Steers about as tight as my Hyper St truggy. It is a bit different however, as the pivot point moves forward towards the center of the truck. It will take some time to get all the alignments down. I may need a stiffer servo spring as well, the stocker seems to allow quite a bit of movement even when tight.


I'll have to get some video, but I stripped the plastic servo arm in front today climbing and leaping off mulch mountains.