Different spring rates with stock ECX shocks?

rockit11

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Does anyone know of a spring that will fit with the stock shocks? The shocks seem pretty good but the front springs are definitely too stiff even with using the softest settings for mounting holes.
 
FYI for others that want to fix the poor spring rates (mostly front) of the Boost, Tower Hobbies lists the T4 fronts at 2.25" (1580) and the T4 rears at 2.75" (1582). Also, to use the innermost holes on the front upper shock mounts you will need an aluminum spacer and longer screws.
 
Trucks have longer suspension arms and thus the T4 springs will be too stiff for the shorter arms on the Boost. I know. I tried the Associated B4 buggy spring set on my boost. The lightest spring in the set was too stiff! Never mind the truck set.

I've found that a great option is the old Losi springs. Unfortunately they can be difficult to find but I've had good luck with checking in hobby shops and on Ebay.
I also use Traxxas 2668 spring cups- they are a slightly larger diameter and fit the Losi springs better than the stock ECX spring cups.

Losi spring part numbers
FRONT BUGGY SPRINGS
Losi Part #
LOSA5128 2" Spring 2.5 Rate (Red)
LOSA5129 2" Spring 2.9 Rate (Orange)
LOSA5130 2" Spring 3.2 Rate (Silver)
LOSA5132 2" Spring 3.5 Rate (Green)
LOSA5134 2" Spring 3.8 Rate (Blue)
LOSA5135 2" Spring 4.1 Rate (Black)

REAR BUGGY & TRUCK (front and rear) SPRINGS
Losi Part #
LOSA5144 2.75" Spring 1.4 Rate (Gold)
LOSA5146 2.75" Spring 1.6 Rate (Gray)
LOSA5147 2.75" Spring 1.8 Rate (White)
LOSA5148 2.75" Spring 2.0 Rate (Yellow)
LOSA5150 2.5" Spring 2.3 Rate (Pink)
LOSA5152 2.5" Spring 2.6 Rate (Red)
LOSA5154 2.5" Spring 2.9 Rate (Orange)
LOSA5156 2.5" Spring 3.4 Rate (Silver)
LOSA5158 2.5" Spring 3.7 Rate (Green)
LOSA5160 2.5" Spring 4.1 Rate (Blue)

I also use these on my Circuit ST. In this post I've detail the shock setup which is very similar to the setup on my Boost. (I use red front springs and orange rear springs). I've found that the 2.5" rear springs also fit the Boost front shocks, so you get a bit more flexibility in application there.

Ultimately the problem is that the Boost uses the Circuit truck's front shock tower so the geometry is all wrong. It's VERY difficult to get proper sag.
 
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I r beej is right about the t4 front springs being much stiffer than the stock rears. I have had good luck with the blue B4 front spring on the boost fronts but I am racing on clay

IMG_20180116_165324694.jpg IMG_20180116_170029308.jpg
 
so I got to try some 2" associated T4 2.99s (green). 2.99 is definitely stiffer than the stock front springs. The lightest losi spring at 2.5 is probably on par with the stock spring? Seems like I'd be looking for something 2.0lbs or less. I currently have 30wt oil in all 4 corners. The light front end on this buggy really wants to bounce around with it's stock springs. I could try a B4 front shock tower, I don't know how much info we have on that.
 
The B4 front shock tower does fit. You would just need to mount some B4 shocks (or something with similar dimensions).

The ECX Boost's front shocks are so long that you can get away with using the Losi 2" long springs so then you could (if you can find 'em) use the pink/2.3 rate spring.

I can't remember if you mentioned that you added weights to the front or not. If not, add some stick on weights under the servo arm.

None of this will truly solve the Boost's front suspension "issue" as the car is fundamentally flawed. As I mentioned in another Boost thread, the buggy was simply a repurposing of much of the Circuit ST platform: it has shorter suspension arms and a shorter chassis. The front shock tower is the same as used on the truck so the suspension arms are going to have less leverage. :(
 
Do you mean "These 2.5" Losi Pink Springs"?
*I do also have a pair of the vintage Losi black/natural with pink index 2.75"springs
*Make me an offer...they can be yours...Not sure I would be willing to part with the vintage Losi shocks though..springs, no problem.losi pink.jpg
 
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I have a set of front shock from the monster truck and one set from a flat track car.. the flat track cars spring seem to be stiffer... is that what I should run???
 
I also have a set of rear for amonster truck and then a flat track which one would you guys run?? and on these care the spacers do you runs the spacer clamp on the shocks? i have read about bad turning problem just wondering what is the best way to set it up.. Iwas given a monster truck and flat track the monster truck works so i am converting it to flat track changing tires and maybe shocks and all.. ANY suggestions would be apreciated on the shock setup on these cars and anything to do to the frontend to get rid of the flar somewhat.,.. BTW i will be running 30 weight shock oil..

ALSO if anyone needs traxxis stock parts ive got a few and also a losi nitro flatrack with TONS of accessories i would trade for a 4wd electric buggy or flatrack..

Nice to be here guys thanks
 

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