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He noted that in his write up. The motor shaft was too short to properly attach the pinion he was using.
Converting the AMP MT to a Circuit ST (to race!)
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He noted that in his write up. The motor shaft was too short to properly attach the pinion he was using.
i_r_beej
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1. The track is in Salem, Oregon at RC Plus. It's a small indoor track on "Astro" carpet. There's a larger indoor track located in Albany, another 45 minutes drive farther south. Haven't been there yet.
2. Yes, the 175RC pinion did solve a problem for me and I'll continue to use it. I plan on taking the steel Robinson pinion to a bench grinder to grind away about 1mm of material on the teeth side so that the set screw will properly engage the flat on the motor shaft. If that doesn't work, I'll just buy a few 175RC pinions and replace as they fail.
I'll post photos later of the fitting issue.
valve90210
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Any more to report, more racing done etc?
i_r_beej
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Update: The Circuit now has three races under its tires and it's doing... okay. Really, it's just the driver that's doing okay; the car can only respond to radio signals. 
With the TLR 22 3.0 buggy, I can hold my own against a field of of comparable cars and generally finish mid-pack (my only excuse is my lack of practice). In the Truck class (Associated T5Ms, TLR 22Ts and the occasional SCT) I'm always coming in last place. I'm crashing less and getting to the point now where I'm driving the Circuit according to its handling idiosyncrasies.
About those: The truck suffers from tremendous understeer under power. I can drive through a turn at about no more than 25% throttle (or coast) but any brisk application of throttle and the truck will just overshoot the turn and plow into the wall. It's rear-weight bias also requires fine control on the jumps: a little too much throttle and it will loop out (back flip). A tap of the brake as the truck crests the jump will level it out nicely, but waiting a split second too long will require heavy braking to bring it's skyward nose back to the level.
As an aside, I may have mentioned it before, but the Circuit feels completely different from the TLR buggy. Interestingly, while on the stand waiting for the Truck class race to start another driver (who also raced against me in the Stock Buggy class) asked me if I thought that driving trucks "felt totally different than buggies." So obviously it's not just me!
Anyway, the Circuit is still teaching me the lesson "It's not the car, it's the driver." And so far it's been a fun and occasionally frustrating ride.
On to tech notes:
When I experienced issues with "standard" metal pinions fitting properly on the motor shaft, I was turned onto RC175 plastic pinions as a problem solver. I had intended to grind down the metal Robinson pinion in the hopes of making it fit and returning to a more durable pinion. However, three races in and the RC175 plastic pinion shows no sign of failing and is very quiet (others have commented on how quiet the Circuit is on the track). It's attached to a 13.5T motor and is pushing around a 1,700+ gram truck and will even pop wheelies from a stand-still, so I'm not even going to bother grinding down the steel pinion. If the RC175 pinion fails, I already have a replacement on-hand! I'm so impressed with their performance that I've installed one in my TLR 22 buggy (which is a less demanding application than the truck).
In the images below you can see the 28T pinion in place. The 175RC pinion is 6mm and the Robinson is 9mm. You can see how the RC175 pinion is flush with the end of the motor shaft and has about 1.5mm clearance between it and the motor mount plate.
More race and tech updates will follow in the weeks and months ahead as I'm continuing to tweak the car to better withstand the rigors of racing.
With the TLR 22 3.0 buggy, I can hold my own against a field of of comparable cars and generally finish mid-pack (my only excuse is my lack of practice). In the Truck class (Associated T5Ms, TLR 22Ts and the occasional SCT) I'm always coming in last place. I'm crashing less and getting to the point now where I'm driving the Circuit according to its handling idiosyncrasies.
About those: The truck suffers from tremendous understeer under power. I can drive through a turn at about no more than 25% throttle (or coast) but any brisk application of throttle and the truck will just overshoot the turn and plow into the wall. It's rear-weight bias also requires fine control on the jumps: a little too much throttle and it will loop out (back flip). A tap of the brake as the truck crests the jump will level it out nicely, but waiting a split second too long will require heavy braking to bring it's skyward nose back to the level.
As an aside, I may have mentioned it before, but the Circuit feels completely different from the TLR buggy. Interestingly, while on the stand waiting for the Truck class race to start another driver (who also raced against me in the Stock Buggy class) asked me if I thought that driving trucks "felt totally different than buggies." So obviously it's not just me!
Anyway, the Circuit is still teaching me the lesson "It's not the car, it's the driver." And so far it's been a fun and occasionally frustrating ride.
On to tech notes:
When I experienced issues with "standard" metal pinions fitting properly on the motor shaft, I was turned onto RC175 plastic pinions as a problem solver. I had intended to grind down the metal Robinson pinion in the hopes of making it fit and returning to a more durable pinion. However, three races in and the RC175 plastic pinion shows no sign of failing and is very quiet (others have commented on how quiet the Circuit is on the track). It's attached to a 13.5T motor and is pushing around a 1,700+ gram truck and will even pop wheelies from a stand-still, so I'm not even going to bother grinding down the steel pinion. If the RC175 pinion fails, I already have a replacement on-hand! I'm so impressed with their performance that I've installed one in my TLR 22 buggy (which is a less demanding application than the truck).
In the images below you can see the 28T pinion in place. The 175RC pinion is 6mm and the Robinson is 9mm. You can see how the RC175 pinion is flush with the end of the motor shaft and has about 1.5mm clearance between it and the motor mount plate.
More race and tech updates will follow in the weeks and months ahead as I'm continuing to tweak the car to better withstand the rigors of racing.
Last edited:
i_r_beej
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Update: Five races under its wheels now and the Circuit is starting to show some signs of the unforgiving nature of racing. The body has several cracks and splits and is generally scuffed and beaten. Trucks, both Stadium and SCTs, have larger tires and thus are able to drive over just about anything on the track. And with their exposed wheels, any close encounter between Stadium Trucks usually ends with one truck going over the top of another! If you look closely, you'll see the dusting of astroturf fuzz on the body.
A strong hit to the front end tweaked one of the stock front swingarms and distorted the hinge-pin hole enough so that the arm had even MORE play than usual. I replaced all four swing arms with the RPM models and the difference was "night and day." The RPM arms eliminated almost all of the play that was present in the stock arms, both at the inboard hinge and outboard spindle carrier hinge. Fantastic! I highly recommend installing both the front and rear RPM swing arms!
I started out with the Traxxas "big bore" shocks on the Circuit have since switched to the ECX aluminum shocks. I still run the Losi springs for more tuning options and also use Traxxas 2668 spring retainers. As a side note I discovered that the Traxxas 3768 lower retainers are slightly larger diameter for the spring and a slightly smaller diameter for the rod end and thus will NOT fit the Losi springs and fit too tightly on the ECX rod ends. The lower spring retainers from Traxxas 2668 fit Losi and ECX springs nicely and also fit snugly on the ECX rod ends. Perfect!
When I first set up the AMP-to-Circuit, I was having a difficult time taming a rear end hop/bounce. In the end, I had very soft combination of 25wt/275cSt oil and a 2.0 rate spring and STILL had a hop when dropping the car. I theorized that it was the relatively hard AKA red (soft) tire inserts that were actually responsible for the bounce. One evening, on a whim, I reinstalled the stock plastic shocks from the AMP and dropped the car. No bounce. None. What??
The main structural difference between the Traxxas Big Bore shocks and the ECX shocks is that the ECX shocks have a captured ball in the shock cap whereas the Big Bores do not. Their bushing design will only allow rotation in a single plane, no angular pivoting. I wondered if perhaps the Big Bores were binding just enough to prevent a smooth operation. (The indoor race track reveals all flaws!) I know that the plastic bodies on the stock ECX shocks are not perfectly parallel but have a slight "hourglass" shape that would affect damping response through the piston stroke. Not wanting to bother with that I purchased and installed the ECX aluminum shocks. They're nice enough but I think the external seal cartridge is poorly designed: it does not utilize spacers like other quality shocks. Oh well, install a couple of x-ring type o-rings (Traxxas, Associated, or Kyosho all produce x-ring type o-rings) and they perform well enough.
I can't remember any particularly nasty crash, but at the end of the April 15 race day, I noticed that one of the bullets on the motor was bent at an odd angle. Closer inspection revealed that the lead contact itself was cracking and was made of a copper-coated composite material (like fiberglass). Disassembling the motor revealed that this particular part appeared to not be easily replaceable (and not available as a repair part from Hobbywing). I desoldered the bullets an cut off the damaged part and then cut down the other two contacts for the sake of symmetry. I used a medium grit nail file board and removed the paint on the contacts, revealing the copper contacts. Resoldering the leads directly to these new contacts was a trivial matter and the motor seemed to work well. Hopefully the new lead joints will last!
Another recent change was the installation of stock ECX Circuit wheels and Schumacher Minispike tires with soft Schumacher inserts. The Schu inserts feel like nothing compared to the AKA red (soft) inserts! My initial setup had been Schumacher Stagger Ribs on the front and Minipins on the back mounted to JConcepts Associated T4-compatible wheels. As I mentioned earlier in this thread, I had to install the wide drive hexes (Traxxas Slash) and an additional 2mm of shims in the front so that the JConcepts wheels would clear the steering links (and they would still rub during cornering). Running the Minispikes at the front helped with steering tremendously. The truck now has a slight oversteer problem! I'm experimenting with trimming some of the knobs to reduce traction a little. So far I've only cut off the outer-most row of knobs to reduce the grabby nature of the tires in mid-to exit- traction.
Unfortunately the winter/spring series is complete so outside of open track practice I may not get a chance to continue working with the Circuit. However, there is the possibility of a local outdoor dirt track opening up for the summer so I may purchase some dirt tires and take the Circuit out to play on a "real" offroad track. I expect it would probably do much better in the dirt due to its rear-motor chassis.
A strong hit to the front end tweaked one of the stock front swingarms and distorted the hinge-pin hole enough so that the arm had even MORE play than usual. I replaced all four swing arms with the RPM models and the difference was "night and day." The RPM arms eliminated almost all of the play that was present in the stock arms, both at the inboard hinge and outboard spindle carrier hinge. Fantastic! I highly recommend installing both the front and rear RPM swing arms!
I started out with the Traxxas "big bore" shocks on the Circuit have since switched to the ECX aluminum shocks. I still run the Losi springs for more tuning options and also use Traxxas 2668 spring retainers. As a side note I discovered that the Traxxas 3768 lower retainers are slightly larger diameter for the spring and a slightly smaller diameter for the rod end and thus will NOT fit the Losi springs and fit too tightly on the ECX rod ends. The lower spring retainers from Traxxas 2668 fit Losi and ECX springs nicely and also fit snugly on the ECX rod ends. Perfect!
When I first set up the AMP-to-Circuit, I was having a difficult time taming a rear end hop/bounce. In the end, I had very soft combination of 25wt/275cSt oil and a 2.0 rate spring and STILL had a hop when dropping the car. I theorized that it was the relatively hard AKA red (soft) tire inserts that were actually responsible for the bounce. One evening, on a whim, I reinstalled the stock plastic shocks from the AMP and dropped the car. No bounce. None. What??
The main structural difference between the Traxxas Big Bore shocks and the ECX shocks is that the ECX shocks have a captured ball in the shock cap whereas the Big Bores do not. Their bushing design will only allow rotation in a single plane, no angular pivoting. I wondered if perhaps the Big Bores were binding just enough to prevent a smooth operation. (The indoor race track reveals all flaws!) I know that the plastic bodies on the stock ECX shocks are not perfectly parallel but have a slight "hourglass" shape that would affect damping response through the piston stroke. Not wanting to bother with that I purchased and installed the ECX aluminum shocks. They're nice enough but I think the external seal cartridge is poorly designed: it does not utilize spacers like other quality shocks. Oh well, install a couple of x-ring type o-rings (Traxxas, Associated, or Kyosho all produce x-ring type o-rings) and they perform well enough.
I can't remember any particularly nasty crash, but at the end of the April 15 race day, I noticed that one of the bullets on the motor was bent at an odd angle. Closer inspection revealed that the lead contact itself was cracking and was made of a copper-coated composite material (like fiberglass). Disassembling the motor revealed that this particular part appeared to not be easily replaceable (and not available as a repair part from Hobbywing). I desoldered the bullets an cut off the damaged part and then cut down the other two contacts for the sake of symmetry. I used a medium grit nail file board and removed the paint on the contacts, revealing the copper contacts. Resoldering the leads directly to these new contacts was a trivial matter and the motor seemed to work well. Hopefully the new lead joints will last!
Another recent change was the installation of stock ECX Circuit wheels and Schumacher Minispike tires with soft Schumacher inserts. The Schu inserts feel like nothing compared to the AKA red (soft) inserts! My initial setup had been Schumacher Stagger Ribs on the front and Minipins on the back mounted to JConcepts Associated T4-compatible wheels. As I mentioned earlier in this thread, I had to install the wide drive hexes (Traxxas Slash) and an additional 2mm of shims in the front so that the JConcepts wheels would clear the steering links (and they would still rub during cornering). Running the Minispikes at the front helped with steering tremendously. The truck now has a slight oversteer problem! I'm experimenting with trimming some of the knobs to reduce traction a little. So far I've only cut off the outer-most row of knobs to reduce the grabby nature of the tires in mid-to exit- traction.
Unfortunately the winter/spring series is complete so outside of open track practice I may not get a chance to continue working with the Circuit. However, there is the possibility of a local outdoor dirt track opening up for the summer so I may purchase some dirt tires and take the Circuit out to play on a "real" offroad track. I expect it would probably do much better in the dirt due to its rear-motor chassis.
nimbuzz
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- Bay Area, CA
Another AWESOME bunch of info = Thanks!! Ya, the rear motor should do better on dirt--keep us posted!
1--Do others at your track us those tires? 2--A little weight out front on that bumper might help traction--what do you think?
1--Do others at your track us those tires? 2--A little weight out front on that bumper might help traction--what do you think?
Sorry for the dumb question, I'm sure you allready posted this info in your first write up. I just couldon't seem to find the answer.
I'm interested in putting a circuit body on my amp, as it looks better. What parts do I need exactly to make this happen ? Just a rear circuit body mount or ?
Thx
I'm interested in putting a circuit body on my amp, as it looks better. What parts do I need exactly to make this happen ? Just a rear circuit body mount or ?
Thx
i_r_beej
Well-Known Member
- Messages
- 993
Not a dumb question- I failed to include a part number reference in my posts.
To mount the Circuit body (and I agree, it's a nice looking body compared to the AMP truck) you'll want the Circuit rear shock tower. Unfortunately the front and rear towers are sold as a set: ECX1020 Shock tower set. You could also use the rear aluminum tower ECX331001.
Hot Racing also makes a nice looking rear tower that I'm considering: The ECT3006 tower. It looks like it provides more positions for adjusting top mounting of the shock and some holes along the center which would be useful for installing an anti-sway bar - a project that i've been considering for a while now.
To mount the Circuit body (and I agree, it's a nice looking body compared to the AMP truck) you'll want the Circuit rear shock tower. Unfortunately the front and rear towers are sold as a set: ECX1020 Shock tower set. You could also use the rear aluminum tower ECX331001.
Hot Racing also makes a nice looking rear tower that I'm considering: The ECT3006 tower. It looks like it provides more positions for adjusting top mounting of the shock and some holes along the center which would be useful for installing an anti-sway bar - a project that i've been considering for a while now.
Awesome - thanks a bunch !
I'll probably just go with the plastic setup, I'm trying to stay away from hotracing as I have there driveshafts and have had a terruble experience with them. I've had to order replacement parts to fix them 3 times allready, I allready have some traxxas driveshafts in my parts box ready to throw on next time they go.
I'll probably just go with the plastic setup, I'm trying to stay away from hotracing as I have there driveshafts and have had a terruble experience with them. I've had to order replacement parts to fix them 3 times allready, I allready have some traxxas driveshafts in my parts box ready to throw on next time they go.
RC Rebels
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- 84
- Location
- Pittsburgh Pennsylvania
This is definitely one of my favorite threads I watch. So much useful information. And seeing how you and your truck progress during races is awesome. I haven't raced at a track in years. The good old days.
Do racers still do what they Can to help each others in the pits area?
Also what has been your best finish so far?
Do racers still do what they Can to help each others in the pits area?
Also what has been your best finish so far?
i_r_beej
Well-Known Member
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- 993
Cool- I'm glad you're finding the posts useful! It's been a definite learning experience for me. High-end kits such as the Associated B5/B6 and TLR 22 series are fantastic and complex and sophisticated but it's the ECX cars (my Boost and AMP/Circuit) that have taught me the most. After prepping the Circuit to race, I almost immediately started to hunt for a TRL 22T roller. I may still get a high-end Stadium Truck but I've decided to stick with the Circuit for the foreseeable future.
Last weekend I raced at a new (to me) indoor carpet track. Traction was considerable higher than on the astro track I've been racing on so it was like learning how to drive all over again. Interestingly one of the cars in the ST class was a converted Traxxas Bandit! And the driver was doing REALLY WELL with that car! We had an interesting conversation about the handling quirks of low-end rear-motor cars and that made me decide to just continue with the Circuit.
One thing I discovered (despite having heard about the phenomenon of "diffing out") was the cause of what I perceived as weird "grabby" behavior of the Circuit upon exiting some turns. The car was rolling to the outside and the inside rear wheel was lifting up just enough to break traction and spin ("diffing out"). Once the car rolled back just a little, the car would lurch forward, frequently causing me to overshoot the turn, crash, or just cause a momentary loss of control.
Unfortunately the ECX differential is not sealed. I have read a "hack" to seal the housing but I think I will first try to pack it with a thick grease to limit the "slip" of the differential and prevent or limit the wheel slippage.
Oh, and yeah, the racer community as a whole are a mutually supportive group. There are some asses, sure, but there always are.
Last weekend I raced at a new (to me) indoor carpet track. Traction was considerable higher than on the astro track I've been racing on so it was like learning how to drive all over again. Interestingly one of the cars in the ST class was a converted Traxxas Bandit! And the driver was doing REALLY WELL with that car! We had an interesting conversation about the handling quirks of low-end rear-motor cars and that made me decide to just continue with the Circuit.
One thing I discovered (despite having heard about the phenomenon of "diffing out") was the cause of what I perceived as weird "grabby" behavior of the Circuit upon exiting some turns. The car was rolling to the outside and the inside rear wheel was lifting up just enough to break traction and spin ("diffing out"). Once the car rolled back just a little, the car would lurch forward, frequently causing me to overshoot the turn, crash, or just cause a momentary loss of control.
Unfortunately the ECX differential is not sealed. I have read a "hack" to seal the housing but I think I will first try to pack it with a thick grease to limit the "slip" of the differential and prevent or limit the wheel slippage.
Oh, and yeah, the racer community as a whole are a mutually supportive group. There are some asses, sure, but there always are.
i_r_beej
Well-Known Member
- Messages
- 993
Last weekend I hit the track for some testing of a new motor in the 22 30.0 and to install/upgrade the front camber links on the ECX Circuit to Traxxas 3745 links. The RPM ball cups/rod ends are now popping off far too frequently and in the last race the steering rod completely fell off causing me to miss several laps as a kind corner marshal made the trackside repair (not at all required, but greatly appreciated as it was still early in the race). I'd decided that a stronger, less flexible camber link would help reduce the amount of backwards flex of the swing arm under impact and thus reduce the frequency of detached links. The only potential issue I see is the links bending and deforming since they are steel and not titanium (like the Associated turnbuckles) or pulling out the mounting screws and/or causing more serious damage that way. I didn't crash test the truck but we'll see how this goes. Here's a few photos of the installation and a comparison of the weights of the two links.
The installation was fairly straightforward and easy. I had to turn the rod ends in a little as they were too long right out of the package. The Traxxas rod ends don't have wrench flats so it was a bit more fiddly to make the initial adjustment. Not that they are on the car it's no issue at all. I'm a little bummed to lose the anodized blue links but I think the titanium was just far too flexible when paired with the flexible RPM and ECX plastics.
I know that one of the most-touted attributes of titanium is its light weight. So compared the two links on the scale:
Wow! The Traxxas links were almost three times the weight of the Associated links! (2.7 times to be a bit more precise).
Next I'll be filling the differential with 30,000cSt grease to see if that will help with traction (especially on carpet/astro). Since we're heading into outdoor dirt season, that may be problematic but I hope to do some testing this weekend.
The installation was fairly straightforward and easy. I had to turn the rod ends in a little as they were too long right out of the package. The Traxxas rod ends don't have wrench flats so it was a bit more fiddly to make the initial adjustment. Not that they are on the car it's no issue at all. I'm a little bummed to lose the anodized blue links but I think the titanium was just far too flexible when paired with the flexible RPM and ECX plastics.
I know that one of the most-touted attributes of titanium is its light weight. So compared the two links on the scale:
Wow! The Traxxas links were almost three times the weight of the Associated links! (2.7 times to be a bit more precise).
Next I'll be filling the differential with 30,000cSt grease to see if that will help with traction (especially on carpet/astro). Since we're heading into outdoor dirt season, that may be problematic but I hope to do some testing this weekend.
Jeb
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- 337
- Location
- West Glover, VT
Thanks for the thread, it really helped as I transformed my amp into a racing Blazer. I'm still working on getting the truck to corner better though. I've heard multiple times that my truck is sitting too high. Still using stock shocks with 35 weight oil and the collars removed in the front and added 35 grams of lead on the front end. it's hard finding the right balance on our loose dirt track with a monster jump and multiple triple bumps.
i_r_beej
Well-Known Member
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- 993
I watched that video of your truck on the track and I noticed that the rear is bouncing a fair bit, relative to the front. I run 425cSt (35wt) Associated oil in the rear shocks (ECX aluminum shocks with Kyosho "x-ring" o-rings) and 350 cSt (30wt) Associated in the front shocks (ECX aluminum with Kyosho x-rings). I also use Losi springs since those provide more tuning options than just the stock ECX springs. I've found that the Traxxas 2668 spring cups work well with ECX shocks and provide a better grip on the Losi springs.
I don't yet know what the rates of the ECX springs are, but here's a handy chart (with part numbers) for the Losi springs
NOTE: The buggy springs are a good fit on the front of the AMP/Circuit shocks. The 2.5in "truck front" springs are a little long and wind out with some pre-load when installed on the ECX aluminum shocks. I've had the best luck finding the Losi springs at local shops as they are officially discontinued.
FRONT BUGGY SPRINGS
Losi Part #
A-5128 2" Spring 2.5 Rate (Red)
A-5129 2" Spring 2.9 Rate (Orange)
A-5130 2" Spring 3.2 Rate (Silver)
A-5132 2" Spring 3.5 Rate (Green)
A-5134 2" Spring 3.8 Rate (Blue)
A-5135 2" Spring 4.1 Rate (Black)
REAR BUGGY & TRUCK (front and rear) SPRINGS
Losi Part #
A-5144 2.75" Spring 1.4 Rate (Gold)
A-5146 2.75" Spring 1.6 Rate (Gray)
A-5147 2.75" Spring 1.8 Rate (White)
A-5148 2.75" Spring 2.0 Rate (Yellow)
A-5150 2.5" Spring 2.3 Rate (Pink)
A-5152 2.5" Spring 2.6 Rate (Red)
A-5154 2.5" Spring 2.9 Rate (Orange)
A-5156 2.5" Spring 3.4 Rate (Silver)
A-5158 2.5" Spring 3.7 Rate (Green)
A-5160 2.5" Spring 4.1 Rate (Blue)
jbalsamo23
Active Member
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- 34
Hi, Great write up,
Can you tell me the part numbers for the big bore traxxas shocks you used?
Do you still recommend them?
I plan an racing on a indoor clay track with my Amp/Circuit
Can you tell me the part numbers for the big bore traxxas shocks you used?
Do you still recommend them?
I plan an racing on a indoor clay track with my Amp/Circuit
i_r_beej
Well-Known Member
- Messages
- 993
Hi @jbalsamo23 I used the Traxxas 5862 big bore set. It's actually a combination of the Traxxas 2660 and 2662 shocks (although those don't come with springs like the 5862 set does).
Honestly though I CANNOT recommend the Traxxas shocks as a good upgrade. As I mentioned in an earlier post, they don't allow for four-way pivoting at the top mounting point like ECX shocks (with their captured ball pivots) or other shocks like AE or TLR. I tried to find workaround in the form of another brand's shock cap bushing but I couldn't find anything that fit- most were just too small. I think this leads to some binding that degrades the overall performance, especially at the rear end.
The included progressive springs are also far too stiff for the truck and they seem to be universally hated in the Traxxas community. *shrug*
It was an interesting experiment and in the end I came to realize that the ECX aluminum bodied shocks are actually quite good. However, in my application I made a few tweaks. (See post #25 above) To recap: I use the ECX aluminum shocks but replace the seals with Kyosho "x-rings." You can continue to use the stock black springs and do just fine but I can't help but continue to tweak so I also use Traxxas 2668 lower spring cups and LOSI springs (the LOSI springs are slightly larger in diameter and thus don't fit the stock ECX spring cups very well). But bottom line- the ECX aluminum shocks are my pick. Comparatively inexpensive and they work well.
Once you get racing, please share your experiences!
Honestly though I CANNOT recommend the Traxxas shocks as a good upgrade. As I mentioned in an earlier post, they don't allow for four-way pivoting at the top mounting point like ECX shocks (with their captured ball pivots) or other shocks like AE or TLR. I tried to find workaround in the form of another brand's shock cap bushing but I couldn't find anything that fit- most were just too small. I think this leads to some binding that degrades the overall performance, especially at the rear end.
The included progressive springs are also far too stiff for the truck and they seem to be universally hated in the Traxxas community. *shrug*
It was an interesting experiment and in the end I came to realize that the ECX aluminum bodied shocks are actually quite good. However, in my application I made a few tweaks. (See post #25 above) To recap: I use the ECX aluminum shocks but replace the seals with Kyosho "x-rings." You can continue to use the stock black springs and do just fine but I can't help but continue to tweak so I also use Traxxas 2668 lower spring cups and LOSI springs (the LOSI springs are slightly larger in diameter and thus don't fit the stock ECX spring cups very well). But bottom line- the ECX aluminum shocks are my pick. Comparatively inexpensive and they work well.
Once you get racing, please share your experiences!
jbalsamo23
Active Member
- Messages
- 34
Thanks for the advice and the quick response