My suspension tips and tricks

[varunaX]

So i’ve had my merv for a while now and found the most interesting and frustrating aspect of it to be the suspension. It took me a while to try out all of the different shocks, springs, oils, rocker configs to understand how it all works. It took quite a while, but i finally found a config that works for me and while Im sure this info may be common knowledge to most of you guys, my hopes is that shareing my learnings may be able to help out those just starting out and make it a little less confusing. It may be overkill, but i kinda wish i knew all this stuff when i started out, i know it would have saved me alot of time and money.

Ill start by saying i drive my car 50/50 on the street and on grass/dirt. What ive found is a suspension setup that really works for this hybrid driving. I will list my config at the end but for now heres some of what i learnt. You might disagree and thats fine, again this is all my personal experience.
First off, The biggest mistake i made when starting out is how much i cared about how much the suspension there was when i push the car down at rest. I would always want the most amount of suspension, as i thought that was the way to go, ie. “wow look at all that suspension!’ . What i learnt is what you should be concerned about is the opposite. You really want the most amount of suspension travel when you PICK UP the car from rest. What that does is it lets the car stay level when you drive over potholes or divots in the grass as the suspension arm will dip into the hole and the chassis will remain level. Since You are never going to be going full speed over a huge rock, it doesn’t really matter how much ‘push down’ suspension there is. The only reason you should be concerned about how much ‘push down’ travel there l is if you want to raise your ride height. The more push down travel you have, the higher your car will be off the ground.

I find if you keep the drive shafts a bit higher than horizontal at rest, thats the best bet. So you push your car down and when it rebounds, have the shafts raise just over horizontal. And when you pick the car up, you really want the springs to expand 75% of way out. The more ‘pick up’ travel you have also allows you your car to survive much bigger jumps as the shocks will expand 100% on a jump, so you have that 75% to soak it up when it lands. This is all accomplished via the shock preloads. The looser the preloads, the more ‘pickup’ travel youll have. The higher your preloads the more ‘pushdown’ travel youll have. Of course this is done the same with looser and stiffer springs

Rebound speed. So i used to care about how fast or slow the car rebounded when i pushed it down and how fast/slow it took to return. I always thought slow was better than fast, but really its trivial. What you do need to care about is how SMOOTH the car rebounds. You want to make sure that the car rebounds in a such a manner that it doesn’t jerk up right away: That means your springs are too stiff. Or if your car doesnt rebound at all or takes a while to return: that means your springs are too loose. This is the hardest part i found of shock tuning, because the smoothness of the return is all based on the spring and oil combo you use. What makes it even harder is that there is no common or universal combo to go with because its all based on how heavy your chassis is. all chassis will have a different weight, some run 1 battery, some run 2. I will tell you my config later, but all i can say is its all trial and error. Of course the basic guideline is that the heavier oil you use, the stiffer spring you need, which is true. But i found when you have the shock removed from the car and you compress it, you want it to be a smooth expansion. Not slow, and not fast, just smooth

Along these lines, i learnt that you need heavier oil and stiffer springs in the rear. I think it says this in the manual, but i found out its not just because there is more ‘stuff’ in the rear (motor, wing etc) but i hated the way my car ‘squatted’ when i gave it throttle. To fix this, not only do you use stiffer springs, but the preload should also be higher in the back, and what you want to see is when you pick up your car from rest, it should be angled in downward slope towards the front. This will also really help when you land your jumps on the rear, the stiffer suspension will help absorb the blow. I learnt this the hard way by snapping a chassis in the rear because my preload in the rear was the same as the front . at rest the slope should not be as severe, you do want it a tad higher in the back, but when you pick it up with the shocks expanded, it should be.

And here are some of my lessons learned:

- Don’t use the stock suspension setup. Its way too loose for any kind of driving. You risk snapping your chassis if you bash
- Don’t use gpm shocks. They break and the pre load is impossible to adjust
- Get some aluminum shock towers. The plastic ones break, and the tower strength is very a important part of the system
- You want the least amount of preload in your springs possible. if you are preloading past the 1/2 mark on the shock, you need stiffer springs. The more preload you have the more wear on the springs during their life time. Less preload = more compression of the spring which is good
- The sway bars are not necessary. They may help reduce the ‘dog peeing’ stance in a turn, but you lose almost all the individual shock articulation which is a way worse trade off
- You can loosen the rod ends on the push rods which CAN eliminate the ‘bottoming out’ of the car. Meaning you can push the car down all the way, but the chassis will not hit the ground. Im not sure id recommend this as if you take a monster jump, all that energy when you land will be forced onto the shocks and it may not be able to take it. The bottoming out of the chassis helps transfer that energy across the whole car. So imo, you a suspension set up that allows the car to bottom out
- You really need bearings in your rockers and not plastic ones. Other than the wheels, the rockers move the most on the car, so do it a favour and get some bearings.
- I did not like the traxxas black and tan springs. Know they are shorter than the stock springs and require alot more preload than usual. Why they are shorter i have no idea , but they are. Either go with the purple summit springs, or get the 3 spring set in the gpm shocks. Trust me when I say They are by far the best springs out there. I must have like 50 springs in my toolbox, I've tried them all!

So yeah i may have gone on a bit long, but i hope it helps someone out there. If your the person who just likes videos have a look at my setup below. It should give you a visual about how my car rebounds and stuff, which is something ive always wanted to see in other peoples setups. It really works great for me however and i do recommend it to anyone who wants a solid 50/50 setup. I run 2s and sometimes 3s and it holds up. Good luck with yours and feel free to add any feedback or any of your experiences with suspension setups. I use:

- LT rockers. Plastic in the front. Gpm in the back
- Traxxas gtr shocks
- GPM black springs in the front, GPM Silver springs in the back (they come with the gpm shocks)
- 80wt oil all around
- I have 1 small spacer on all my pushrods. this makes my pushrods longer and gets me even more travel
- Bearings in the rockers

[Petertje60]

Nice write up. Makes me want GPM springs.

[GULLY]

thanks, I'm glad I got the purples

[Redsawacs]

Oh, I am sure some will disagree with your personal set up but i sure wont!

everyone sets things up personally for their driving habits and car mods as well as driving conditions...

...I dont think anyone can disagree with your research, at least not without lookin' foolish.

Thank you for the post, I hope it gets "sticky"

[krallopian]

I love it! HUGE range in that suspension! I see you have the summit rear rockers?

** Edit

Ah I see that's the "LT" rockers, I guess that means LONG TRAVEL?

[varunaX]

right. long travel. i experimented alot with the p2 rockers and i really wanted to like them, but they are just too short and dont provide enough up/down range nor enough ride height when needed. the long travels give alot more range to work with and handle just fine at 50 mph. they arnt as soft as youd think when combined with stiffer springs.

i was stripping alot of my rocker hole screws as i was experimenting so often, so i wanted to get aluminum ones. so far no probs. they are the long travel aluminum ones from the toyz. they give alot of travel in the rear as you can see as opposed to the plastic stock l t rockers in the front.

[GULLY]

I want to build a merv just like that, what kind of rockers are they, I didn't think they came in aluminum..

[krallopian]

I'm thinking of reversing my fronts with the rears, my rears are shorter than the front, but I dunno if the shape is the same. I have the black alum ones from the toyz.

[korn0307]

Great information! I just replaced my stock springs with GTR shocks, 50Wt oil, and black and tan springs. I was woundering why the springs were soo much shorter than the purple springs! Im gonna change to purple springs all around and im gonna get some thicker oil.

[GULLY]

yeah mon, way to go.. to bad my hobby shop has no pull, I ordered purple like two weeks ago

[korn0307]

I got mine from amain hobbies. I went to the only hobby store close to me yesterday and they barely carry any 1/16 parts. I was able to get a few pinions t play with gearing and i got a series connector. But im pretty sure they are the same parts that 1/10 scale use.

[Pellogt]

good info!

my merv flip everytime, and i have the black spring in the back and tan in the front. next week is coming the summit spring purple.

how do i know if i have the GTR shocks?

[dwmoss]

varunaX,

thanks for the great information.

dm

[korn0307]

good info!

my merv flip everytime, and i have the black spring in the back and tan in the front. next week is coming the summit spring purple.

how do i know if i have the GTR shocks?

The shaft is a goldish color and the shock body is not plastic i believe its anodized aluminum.

[hemiboy81]

can some one direct me in the right direction to see all the spring rates and colors i have pink summits & thay are 2.77 rate what are purple rates and so on thanks

[50togo]

7145 Spring, shock (GTR) (1.76 rate, orange) (1/16 E-Revo) (1 pair)
7146 Spring, shock (GTR) (1.92 rate, green) (1/16 E-Revo) (1 pair)
7147 Spring, shock (GTR) (2.06 rate, tan) (1/16 E-Revo) (1 pair)
7148 Spring, shock (GTR) (2.22 rate, black) (1/16 E-Revo) (1 pair)
7244 Spring, shock (GTR) (2.77 rate, pink) (1/16 Summit) (1 pair)
7245 Spring, shock (GTR) (2.925 rate, blue) (1/16 Summit) (1 pair)
7246 Spring, shock (GTR) (3.2 rate, purple) (1/16 Summit) (1 pair)


The Table for the MERv is :

7145 Spring, shock (GTR) (1.76 rate, orange) (1/16 E-Revo) (1 pair)
7146 Spring, shock (GTR) (1.92 rate, green) (1/16 E-Revo) (1 pair)
7147 Spring, shock (GTR) (2.06 rate, tan) (1/16 E-Revo) (1 pair)
7148 Spring, shock (GTR) (2.22 rate, black) (1/16 E-Revo) (1 pair)

[hemiboy81]

50 togo were did u find that at ?

[50togo]

Quick web search!

[the finisher]

I've been messing with my suspension a lot lately trying to find a setup that works. Still not quite happy with it. You've got some great info in this write up! It never occured to me that downward suspension travel is that important. I always concentrate on the car not bottoming out. Thanks!!

[agosb]

I have traxxas gtr shocks, with tan and black springs, 80wt oil, and I don't really like how it handles, is no smooth, and when I push my car down it doesn't return at a medium, decent, level.
I don really like them.
Is the purple summit springs going to solve this problem? And the purple goes to front and back also??
Thank you!

[50togo]

You can try purple in rear and blue in the front. Much stiffer then tan &black

[agosb]

wich combination is better? blue (front) and purple (rear)? or purple in rear and front?

[wfburton159]

Thanks for the great write up and video. I need to do something to my stock slash. The stock suspension is way to soft. More stuff to buy.

[50togo]

You have more weight in the rear so little softer spring in front

[mtc777]

Can you please edit it, so there aren`t any "&lsquo", it makes it hard to read....

[BigChet91]

Great write up. Gonna start doing some suspension tuning soon

[braaap58]

Thanks for writing this. I spent the first few months trying set ups that wouldn't bottom out going off a curb. Took allot of time and 50 bucks worth of springs and oil usually making it worse. I thought black and tan drove like crap. I ended up with purples on my own too! Also why does everyone care so much about about the back squatting. It has to, its called weight distribution. So stop worrying about squatting and bottoming out and your car will drive great!

[b08rsa]

Good write up, with what I have found that works for me is totally different since we off road race on a indoor dirt clay track.
I use black springs in front with 35 wt shock oil, tan rear with 30wt. shock oil. I like my front end a little stiffer in the front. a center dif has really improved steering. Front diff 30k, center 30k, rear 30k. We also run the J-concepts Goose Bumps with the Rulex wheels. Talk about a great tire for racing with. We are racing on a track that is designed for 1/10th and 1/8th scale buggies and clearing the same jumps. Once again, great write up.

[subneural]

Great post, thanks for putting it up. I think I am going to put GTR shocks and longer springs on my upgrade path.

[hemiboy81]

varunaX u did agreat job with this thread i have saved it and read it for reference.
i see u used LT in the back are thay for the back or for the front just used for the back?
im glad i got this thread going again looks like its helping answer some questions
p.s. always thanks 50togo

[varunaX]

varunaX u did agreat job with this thread i have saved it and read it for reference.
i see u used LT in the back are thay for the back or for the front just used for the back?
im glad i got this thread going again looks like its helping answer some questions
p.s. always thanks 50togo

Hey it's cool that people are still reading this! A year later and not much has changed on my setup really. Only new tip I can recommend is now I use 3000 wt DIFF oil in my front shocks believe it or not. I use it with the green springs and for some reason it works out really well. A lot slower but very smooth rebound.

Hemi I use plastic lts n the front simply for the more travel it gives me over p2s

[addicted_2_R-C's]

where can you get the spacers for pushrods and the rocker bearings???

[Lilbomb]

Thanks for posting this VarunaX. I just got 2 of these cars for my kids and posted up a suspension question this morning and then found this an hour later. Super helpful. Thank you!!! Now to go buy some parts. lol