FWD/FF Buggy

[ekt]

Have you looked at using TDs new type b suspension mount #TD330579 and motor guard #TD320227 at the front to allow for more material under the front suspension mount?

[Origineelreclamebord]

Thanks guys I have looked at that. It's not economical to replace the chassis plate right now, but the Spec B changes for the front end are on the list if/once the design gets a big update package.

To be fair, the list is quite considerable. If I were to make the package now, probably the only parts to remain untouched are the new suspension arms and long shock configuration It's not that nothing on the car works as it should, it's just that to make the updates in the best way possible, it is best to take no compromises

[Origineelreclamebord]

So, time for some updates!

I've started work on revisions of the current prototype. It continues in the spirit of the current prototype, but the vast majority of the custom parts will change. Some updates are long overdue (like a proper wing mount for the new wing position), some are untested but sure to enhance performance, and lastly, some will open up a lot of new things to test the effects of. This is a teaser of what's in store for the car:



First thing will be the possibility to switch between longitudinal and transverse battery layout for the shorty pack. The longitudinal layout should prove a most useful tuning option to make the car better performing on high traction (and dive less on that outside front wheel into corners) - when the grip is not there, the transverse layout should still prove superior to provide the right forward traction. I have been looking at saddle pack compatability, but it results in complications making the design work without extra parts. Shorty packs are kind of becoming the new standard as we speak, and I think the performance gains of a shorty pack are more considerable in this than a RWD... So the design will remain specifically built for shorty packs only.

Secondly, with the Spec B suspension hangers and motor guard available nowadays, it makes sense to optimize the car for that setup. I've heard some rumours people are having durability issues with carbon chassis plates on the DEX210 - AC's carbon has held up brilliantly so far without any breakages, but it's best not to push luck, so a sturdy 'straight' Spec B plate it is!

As a third update, I want to enable Low Roll Center (LRC) geometry on this car, which at the same time will allow for a kickup angle to be created on the car (up to 3 degrees using standard Durango parts, theoretically up to 6 degrees using RDRP+Durango parts). The kickup will prevent the car from getting negative kickup under braking. This should result in the car requiring less of a change in driving style and should be more a lot more stable and forgiving into corners.

The combination of LRC/kickup and battery layout options will allow a lot more flexibility to adjust the car from low bite to high bite. It's quite weird that the current car has a battery layout that should suit low-bite best, but has a roll center which is more usual to high-bite. I think this (in combination with the lack of kickup) is causing some gaps in performance (like low-bite understeer and high-bite instability issues into corners) that need to be filled.

I can't predict how quick progress will be, but stay tuned: There's more to come soon! I have some updates coming up that are not yet pictured. For example, the steering geometry and steering rack will see major changes that will take out the bump-steer, minimize flex in the steering rack and make for easy ackermann angle adjustments. Also, I have a new rear toe adjustment system in mind for the car (I recall thanks to a suggestion from someone at the Kampenhout GP) For the revised car, multiple front suspension settings will be considered too, and I will be looking into flex levels of both suspension and chassis.

[Origineelreclamebord]

Yesterday I tested the car on (loose) dirt, and tested a 3 degree kickup setting (one of the adjustability features that will be on the updated proto).

The last (TRF201 based) proto was very stable in general, but due to it's lack of ground clearance, droop and the inboard suspension the motor dug into all the holes and bumps that the tires that appear in the dirt track throughout the day.

This year things were different. The front suspension did a lot better on the front end, and as a result the car didn't bottom out on the motor. Also, because the RWDs too struggled to get the power down, acceleration was actually quite close to the RWDs (if I could take the right line coming onto the straight). The car's higher cornering speed really showed too: The RWDs seemed to come to a stall mid-corner, whereas the FWD kept the pace up.

As such, I qualified 3rd (out of 30 drivers). However, I struggled a lot in the first and second finals because the holes in the track were getting bigger and the car lost rear traction very easily - it was all over the place, and coupled with the unusual cornering speed difference I caused a few incidents.

So, time to change the setup for the last heat. I reduced the front droop (2mm limiter in the shock), increased the rear droop (shock eye unscrewed by 2-3mm) and added 40g of underLiPo weight. That did the trick to win the last final, despite dropping back to 8th in the second lap!

In the end, a 5th place (from the second final) and 1st place from the last final gave me 3rd place overall! I'm quite surprised where I ended up: I hadn't raced for 6 weeks, missed the first heat of qualifying (nor had I practiced with the car before going into the second qualifier), and I 'shouldn't' have been in the top 3 normally. The car clearly had a dominant pace and it worked out extremely well!

As for the the 3 degrees of kickup (vs 0 deg): It seemed to smoothen out the steering on-power with a tiny bit more understeer (it was quite snappy at times before), off-power the car felt more predictable. So overall, it seems to make a more comfortable drive. I don't think a clean lap time of either setup would make much of a difference though.

Lastly, a driver who tried the car mentioned some things to work on in the handling (that seemed familiar once he mentioned them): It seemed to off-power understeer at high speeds and off-power oversteer at low speeds. The low-speed oversteer is likely down to the tires I used on the rear (not spiky enough to dig into the soil with the low weight on it off-power), and the high-speed understeer may well be caused by a huge LMR wing on the rear and no downforce features up front

[janus_77]

Originally Posted by Origineelreclamebord

The car clearly had a dominant pace and it worked out extremely well!

Yep. Paul fastest lap was 0,4 sec faster then anyone else in 2wd

edit: on a 27 sec. lap

[Origineelreclamebord]

Originally Posted by janus_77

Yep. Paul fastest lap was 0,4 sec faster then anyone else in 2wd

edit: on a 27 sec. lap

I knew my fastest lap was quick, but I didn't know this statistic yet! Thanks for posting it janus!

Since the race on November the 3rd I've been doing quite a few things on the updated chassis. Also, I've made a 3D printing order today for an experiment on the front suspension:



4WD Front Wheels! There are many reasons why it should work better, and some why it may not.

Pros:
- Little scrub-radius (distance between steering pivot and contact patch).
- Steering geometry and Ackermann angle becomes a lot more 'natural' (close to current 4WD production buggies).
- The front track is wider (because the tires are narrower, which should increase stability and decrease grip roll to the levels quite close to RWDs and 4WDs (after all the FWD is the only buggy using the wide tires up front).
- The donor parts to achieve a working system (on paper) are a standard piece of kit from a widely available car, so these shafts should produce a lot less chatter than the current driveshafts.
- The narrow tire is less prone to ballooning. Ballooning tires cause for a lot of loss in grip (contact patch becomes very round, thus smaller) and power output is often very contrasting between inside and outside wheel (effectively losing part of the power output).

Cons:
- The narrower tire (ignoring tire ballooning) has considerably less surface area, and as such it may lose a lot of the (forward) traction.
- The front end will not be usable at all events/under all tire regulations. As such, at the moment it's only a proof of concept.
- The axles make the car 1mm too wide, whereas both rims and tires fit easily within the regulated space.
- Less DEX210 kit parts are used.

[Origineelreclamebord]

Update time!

...And this time the news isn't so good. I've tested the car on carpet last weekend. I was expecting the car needed a few tweaks to work well, but it was an utter disaster when I arrived: The car was completely undriveable. A lot of setup changes were made: Mini Pins on the rear (to keep it stable over the low-bite sections), much harder front springs (to reduce diving and grip-roll), 5mm limiters in the front shocks (to reduce grip roll and add rear stability), a lower ground clearance (to reduce grip roll), 50g extra weight on the back (to keep the car from diving and making stoppies). It all helped, but it wasn't very good yet.

Since the car wasn't working, I went all for broke and fitted the 4WD front end. I tested it in the break between qualifying and finals, and it went quite well. The geometry with the 4WD front wheels is more natural, and it showed. It also seemed as if the wide tires were just giving too much sideways bite to the car. It wasn't very confidence inspiring yet, but by now I know the car good enough to race with it.

I had been having a few breakages, and the bad luck continued with loads of mechanical problems. All in all, the only heat I finished was the last final of the day. The car was quick enough to become third in the D-finals - I'm no pro, but I should've at least managed a high C-final with a decently set up RWD.

It has taught me perhaps next time I drive a car for the first time on a surface I'm not very familiar with I should try to find some time for a free practice day with the car, not enter it in a race!

Also, with the handling the car showed by the end of the day, it's clear that the car will need a lot of setup work and some design changes to work on carpet.

Stay tuned for more updates, they're due soon!

[skyaflake]

Too bad it didn't work out for you this time. I like the car due it's uniqueness and development progress. It's very nice to see the car from the sideline. It has much nicer movements than a RWD buggy: you can see the car "work".

Hope you have more luck next time.

[Origineelreclamebord]

Thanks Luck is not on my side this week though. I've been discussing the progress with my sponsor, Atomic Carbon.

The car has been showing very good performance on low-bite. However, there were hints that it's stability on astroturf needed some work. On carpet it's an insane thing to drive, and the biggest improvement was the use of narrow tires on driven axles - which as it stands now is not legal in EFRA or BRCA regulations.

It has to be tested whether the performance improvements are down to the actual narrower tire or the much improved suspension geometry. Either way, the car's current performance on high bite surfaces is not impressive, and it's design will stray further away from any existing car to make it work on high bite surfaces.

With limited resources at Atomic Carbon and the project heading further away from their core business - Making Carbon Upgrade parts and Conversions for High-bite Surfaces - the decision was made to stop financial support on the FWD Buggy project.

It's a bit of a setback - especially with an updated design of the DEX210FF nearly completed - but it's an understandable decision. It's been great working together and I'm not sure the project would have got off the ground without them! However, the project is of less relevance for their business, and in the end their sponsorship should be an investment, not a money pit (that's my job ).

So what's next? Well, for now I'll carry on without a sponsorship. Despite the smaller funds, I've got big plans: First of all, I'm going to finish the updated design of the DEX210FF.

Secondly, involving the public has played a big role in the project and has worked very well so far, so I will continue this. I intend to sell several prototypes to those people interested to form a test panel for the development of the buggy. This will help gather more data, and it means the car can be tested and updated for surfaces and tracks I don't normally drive on.

If you're interested to join in on testing the FWD Buggy, you can contact me through a PM.

[Origineelreclamebord]

After last weekend's tough lessons it was time to return to the dirt track for a second time. I used the setup from last time on dirt as a start, but used a little less droop on all four corners, a gear diff and ran different tires back to back.

Competition was more fierce than last time: The pack was running close together and there were some fast drivers that weren't there a month ago. I missed the first qualifying - luckily I could depend on the easy handling and a (mostly) proven setup to do the work. The second qualifying went well but the car seemed a little loose on the rear at times. For the third qualifying I made some changes (more rear droop and a higher ride height front and rear). It was too much, and the car understeered. In the end I had to settle for sixth in qualifying - not as high as the last dirt race, but not bad

In the break between qualifying and finals I tried dBoots Multibytes up front. The car tended to hook with the old setup when it was decellerating from high speed to low, I thought this may be an issue with the rear tires (dBoots Multibytes) providing less bite than the front ones (Losi Step Pins), which would become a problem as rear downforce decreased.

The dBoots didn't really solve that... so that problem may be down to caster and kickup settings in combination with the grip ever increasing as the car leans on the outer front tire, until it reaches a threshold where the car hooks. However, the dBoots did make the car perform a lot better: The carcass doesn't balloon (much) under power whereas the Losi Step Pin does. I noticed before this greatly influences handling: The tire ballooning interferes with the suspension action and makes the car feel nervous and less predictable. With the ballooning gone, the car seemed to have at least as much steering and consistent throughout the corner. Forward traction didn't seem affected much.

At the end of the break I broke down the car in a seemingly small crash. It seemed severe since a rear arm was dangling behind the car. It turned out that the hinge pin had crushed the plastic pivot ball on the outside of the suspension, and that in term caused the hinge pin to pop out in the small crash, whereas the real damage that caused it was probably done last week indoors.

Thanks to a fellow club member I had the car ready again just in time for the finals. In the first final I had a steady race and was running in fourth when someone in front of me had to retire - I continued steadily and had an opportunity to snatch second, but ultimately a little impatience and inexperience resulted in a small mistake and meant I had to settle for third in the end.

The second final had a bit of a messy start - I got caught up in a few tangles. However, when the gaps opened between all the cars the pace of the FWD enabled a comeback to third.

The last head was again a messy start - again I got caught up in a few tangles, and this time caused a few too. After that I made a few errors on my own and I knew it was a done deal position-wise and ended up in tenth.

In the end, the results from the first two heats were enough to score a podium for a second time with the car. I think I proved my point with the FWD on dirt then Now for those other surfaces and managing that hooking handling trait.

[Origineelreclamebord]

Time to blow the dust off this topic again. The bad news: I will not be sharing screenshots of the third prototype. The good news: I've been working on a third prototype since... mid-October?

Anyway, I binned a near-finished model for the third proto as it was building too much on the platform of the second prototype and started over again. A good few months later and the third prototype seems to be only a few steps away from becoming a reality.

The changes on the car are big. To give you an idea: it will share zero custom parts with the old prototype, essentially it's a completely new prototype that happens to be built around the same gearbox

Also, I'm kind of done running an ice cream box for a bodyshell - I promised something better for the second prototype, but I never came around to actually making one. This time around, I want to work on that too. Since that's less of a secret, I thought I'd share some sketches of that to give you an idea of what an FWD Buggy COULD look like:







I will probably be moving away from the styling of the first sketch, meaning I won't try to replicate Durango's styling on the car. Comments and suggestions are welcome!

[alien racing]

Wahoo... You will not share speed FF secrets ? mmmmm...

I'm so excited to race mine in real competition and to meet you in a big race !!!

[Cream]

Originally Posted by Origineelreclamebord

Time to blow the dust off this topic again. The bad news: I will not be sharing screenshots of the third prototype.

Such a shame, but I can't say I'm surprised.

Good luck with the third incarnation. Loving the idea of covering the motor with the shell. Are you thinking of having it fit between the motor and front bumper? X11 style front suspension to keep it low?

[alex97]

when do you think you will be selling these ?

[alien racing]

Originally Posted by Cream

Such a shame, but I can't say I'm surprised.

I am...

I hope I'm not the cause of that ?

[Origineelreclamebord]

Thanks for the replies The pictures I have drawn are just ideas, they do not really take into account what specific geometry the car needs, they are only to study what the aesthetics would ideally be like.

Regarding not showing screenshots of the third prototype, I'd like to think the project - besides being a lot of fun - will result in a car that's fit for production of some kind, so I can make money from selling either the design, teaming up with a company (again) or starting up my own.

To do so, I need a unique design and product. If I keep posting out in the open and in detail what progress I'm making, then people can freely take over this information. For personal use that'd be fine, I like sharing these developments and make people enthusiastic about building stuff yourself. However, I'm not the only person with access to CAD software, the skills to replicate donor parts, design around that and has access to manufacturing methods. With potential of the project increasing it's becoming all the more interesting, and if all new development data keeps flowing onto a forum for free then all it will take at some point is someone with a bigger pocket of cash to release a car based on my hard work without me seeing anything for that in return.

I think Cream points out exactly my thoughts... I find it a shame it's heading this way, but I can't make this project a money pit for someone else's benefit.

@Alex: The answer is a bit complicated, but here we go! I'm looking to get a generally competitive car. The current car is dominant on loose dirt and competitive on grass, o-k on astroturf and clay, but undrivable on carpet. Also, it seems that it's easy handling makes club drivers quicker, but top level drivers can't equal their RWD performance. I'm ok with it if a pro can't (yet) outperform his RWD but a club driver can, in the end club drivers is the large customer group that bring in the money, pro drivers only cost money for a company.

However, I want a car that's at least be flexible enough to drive comfortably on all racing surfaces, and preferably very competitive of course. I can't expect similar performance to RWD everywhere, the FWD principle is too different for that, but I believe my goals are realistic.

When I achieve my goals I can't predict, especially since I have yet to see the performance from all the updates on Prototype No.3 - but this I will find out soon, and then I hope to be able to answer your question more accurately.

[mr. ed]

Just adding to the disucssion: unfortunately most club drivers are not interested in alternatives that fit their driving better; as long as the product does not appear similar enough to what the pro-drivers are using.
The influence those pro-drivers have on the purchase behaviour at club levels is exactly why the pro-drivers get sponsored.

The best that could happen for you is to find a company again that's respected and promotes the car throug an established driver. If it could become the car to have in a new class; whether by outperforming new releases in the same class or as a spec car, then you'd be really set. (think of the supastox)

Outside of clubs, I'm thinking of bashers primarily, the influence of pro-drivers is less. But there 4WD rules, and bigger scales, as speeds get so crazy with 3S and 4S.

[Origineelreclamebord]

I know what you mean mr.ed, exposure with the car and a related pro driver is important.

My main competitor is the RWD Buggy market, and there lies a chance there. With such a different car, you create your own market and demand. The minority of people that are interested in a FWD Buggy is a big enough group to make a conversion kit for. And I think the last few years we have been faced with the impact small companies like Atomic Carbon, Team Xtreme and X-Factory can make by making conversion kits. The TRF201 Mid-Motor is essentially a Vega and the B5M is a clear descendant of the Atomic Carbon S2! Why make a full kit with all the financial risks and long development programmes involved if a few conversion kits can prove the concept and change a market?

As far as I know, these cars were not first run by big guys - yes, very talented and experienced people developed it and helped and the cars did score high at regional and national events, but I think it proves there's more to it than having a big name score with a car and promote it.

As a nice example, if promotion was all that was needed, Tamiya should have had a bigger market share in Europe by now with the TRF201! It's decent parts+setup support and unique selling points of a design that form the basis to have something worth promoting in the first place, and that - without trying to sound harsh - may have played a role in the low percentage of TRF201s running around.

[Origineelreclamebord]

Time for an update! I've been working hard the last few weeks on the finishing touches of prototype No.3, and the 3D printables have been ordered yesterday. The carbon fibre items will be ordered soon. I have a teaser for you in the meantime:




Then lastly, I've ended the chapter of the second prototype on a high. Last weekend, the last race of the 'MAC Vlijmen Winter Championship' (regional dirt indoor races) was run. I ended up in third place in the overall standings! The best three results being two third places with my FWD, and a fourth place with my DEX210. So despite the DEX210 in the picture, it's the FWD that has brought me my best racing result to date!

[Cream]

Originally Posted by Origineelreclamebord

Then lastly, I've ended the chapter of the second prototype on a high. Last weekend, the last race of the 'MAC Vlijmen Winter Championship' (regional dirt indoor races) was run. I ended up in third place in the overall standings! The best three results being two third places with my FWD, and a fourth place with my DEX210. So despite the DEX210 in the picture, it's the FWD that has brought me my best racing result to date!

You missed a trick there. You SO should have had your front wheel drive in your hands..