FF03 4GR with Peugeot 306 Maxi shell - Custom 4 Gear Transmission Rally Car

[svenb]

The tamiya m chassis servo saver 54120 is a good option and fits a treat 👍

[lowspot]

4 minutes ago, svenb said:

The tamiya m chassis servo saver 54120 is a good option and fits a treat 👍

In deed, but please add 51000, as 54120 is just an add on for the high torque servo saver and doesn't include the springs and plastic parts. There is also a note on the packing.

I'm using the same setup and my TL01 drives like on rails now :-)

[lowspot]

There is something else popping up in my head. Don't know how fast you want to go with the TL01 but in theory you can fit a 26T pinion by using the second, smaller gear - the one which is closer to the opening on the opposite side of the motor -  instead of the bigger one.  And at the motor side by using the two holes they are off center, in case you motor has these holes (I hope it makes sense )

I have installed a 11T super modified motor and it does 51mph with 2S brushed. The position on the 3 fixed mounting holes are changing now and that allows you to install a far larger pinion gear.

[ThunderDragonCy]

Threw the front suspension together and ran into a problem - the yeah racing 39mm universals bind. The hit the inner end of the gearbox outdrive before fill compression. The regular dog bones just about clear. I have pulled everything apart and it seems the TG10/TB01 caster c hubs are very slightly narrower than the TL01 kit part, by a couple of mm. I would really like to use the universals. Anyone know if getting the TB01 knuckles will fix this? Or maybe something similar like the TA04 knuckles? Thanks. 

[TwistedxSlayer]

I've got TA04 knuckles with TA04 racing hubs on TB Evo I/II arms with 39mm GPM cvds on my Ultimate slow build. If you need any more measurements let me know.

[ThunderDragonCy]

So for various reasons i didn't get the TL01 running quite. I did get it finished though, with the CVAs off my TA06, the high speed gearset, the suspension shafts, the upgraded uprights. 

Whilst waiting for the TB01 front arms to arrive which would allow me to use the universals at the front, another thing popped onto the radar and i just couldn't resist....

That is a hopped up, very lovely FF03 Pro. And after the removal of the front bumper and a lot of changing of wheelbase and suspension spacers, the Peugeot fits! 

Its not perfect. The wheelbase on the shell is a little short so this is the medium 245mm wheelbase option with all suspension arm and upright spacers at the front to grow the wheelbase to about 249. The stance isn't quite right, but it runs! 

Even with all the spacers forward on the 257 option the rear wheel catches where the shell cuts in to the rear bumper 

I needed to run the front body posts in the top position, which isn't shown in the manual but it obvious when you look at the parts. 

A quick run in the street and it seems really nice. The Pro comes with TRF dampers and a lot of nice blue bits, but none of the plastic is reinforced and it uses plastic suspension blocks, so i have ordered up some alloy blocks, steel pivot balls. Also looking at getting the carbon reinforced K parts which includes the rear deck stiffeners and the steering rack which should improve things a little. Looking forward to getting it dialed in. Going to stick a 17t brushed in it so it's compatible with the Tamiya category at my local club in case i fancy giving it a run around the track. 

And as a result, the TL01 is going on ebay. If anyone wants it with this mad airbrushed lightweight NSX shell it came with, drop me a PM

 

[TwistedxSlayer]

Oooooo  FF03 Pro. Tis a very nice piece of work. I really do fancy a FWD car at some point.

[ThunderDragonCy]

Hop ups day! Alloy suspension blocks, and reinforced K amd M sprues

Although i only wanted the stiffeners and steering parts and shock tower, there a so many other parts on these sprues that the hole rear end got new hard plastics

I could only find 1XC suspension blocks, not 1XD as per kit, but this only makes the track 0.75mm wider. 4mm hexes replacing 5mm make the track a little narrower overall. Rear block is a 1B to maintain the same toe in as the kit. All the plastic pivot balls on the inner shafts replaced with steel. 

Front end partially dis-assembled. The big plastic shock mounting/bulkhead part is also on the reinforced sprue so this is getting replaced. 

Unfortunately when i got down to the steering to replace with hard plastics i found bushings.

I already used my 4 spare 850 bearings because the suspension rockers also had bushings, so that was frustrating. I put the bearings in the steering because it's buried in the chassis and i wanted it back together. The hard plastic parts are like for like replacement but much stiffer. 

The front suspension blocks were next. I had some 1XD split blocks from my TA06 so i used those with another 1XC at the front to give some sweep on the front arms. Wanted to try this. Apparently it takes the edge off turn in but gives more grip on exit. Steel pivot balls again. 

Then it all got a bit frustrating. The new 17t brushed motor needed the yellow wire moving to the bottom, then a new longer blue wire because it then did not reach the ESC. 

Once the front end was back together for some reason the steering connectors were catching on the shock mount plate. Tried the old one and that hit too. Ended up chopping the top off

However, after all this is finally went back together. 

Need to tidy up the wiring but it runs. And runs well. Give it a good run on a damp street and it seems really nice. Bit more tied down. Don't know if it's emporors new clothes, but there is no slop in the suspension now and things are a little stiffer. Don't know, but it's really nice and i am keen to give it some track time. 

[ThunderDragonCy]

Little bit more. The 850 bearings for the IFS rockers arrived so in they went. Smoooth. 

Tried some different springs just to see if the softer 53163 road/rally springs i have would be better. Unfortunately not! Tried a couple of different ride heights, but thry just let it bottom out and skip at the rear too easily, and it was getting lots of roll oversteer. Basically not controlling its masses well. Didn't want to go back to the full hard setup it arrived with (stiffer than i have on my TA06 racecar) so i put the stiffest blue road/rally springs rear (softer than the red hard springs) and the yellow spring from the 53540 hard set on the front. Seemed good. Ended up taking the sway bar off the rear and putting a soft bar on the front and the balance seemed good. Going to try and get some track running soon. 

[ThunderDragonCy]

I appear to have solved the dicey handling. I was suffering from Crap Tamiya Tyre Syndrome. Today i ran it on freezing wet tarmac and it was great. Put the power down, no crazy oversteer all the time. Solution? Sorex 7 spoke 26mm wheels (incidentally the real rally car used 7 spoke wheels) with Schumacher SST tyres. Yellow front and stickier white rear. 

They even look the part for a tarmac rally car. Fan start properly dialling in the handling now i know the tyres stick to the floor! 

[ThunderDragonCy]

Ran a pack through it this afternoon, agaij on freezing damp tarmac. It's brilliant! Tyres have transformed it into a really planted, easy to drive machine. It's even suffering from a bit of understeer now, but i am going to resist fiddling too much. Right now i am just really i have a fun car to drive. Now i am confident in the grip i was happily razzing around at full throttle high speed. Great stuff! Can't recommend these tyres enough if you are doing some street running. I just used some random foams out of some rally block tyres to fill them up. 

[ThunderDragonCy]

Couple of unexpectes upgrades for the FF03 today. I am building a DN01/TRF201 to use up the mountain of spares i have accumulated. One thing i needed to buy new was diff gears and counter gear. I bought reinforced diff gears and the FF03 lightweight counter gear. I popped open the FF03 gearcase to put the lightweight gear in and found a regular white idler, so in went the new reinforced gear and the standard parts are destined for the DN01. Nice tough, light drivetrain

I also picked up some large 0.6mod tamiya pinions as the tamiya class at my club only allows for tamiya gearing. 

The 29t is going on this and the 28t on my TT02 Type S when i build that. It was pretty punchy on 26t pinion so it will be interesting to see if it gets out of hand with this. Its still not very aggressively geared as a racecar goes, but it's pretty blinkin fast for driving in the street! 

 

 

[ThunderDragonCy]

Been quiet on this for a while as mostly i have just been running it occasionally and having fun. I figured out the steering catching issue which was driving me nuts. On an rctech thread someone pointed out the steering arm on the servo side is handed. It looks symmetrical because there's aboyt 1mm different in arm lengths. There's a dot on one side show which way up and it actually in the manual. Flipped it over and all is well. 

Anyway, the reason for the resurrection is that i got reading the kentech blog on his front wheel drive adventures. If you are interested start here and follow the links forward

https://kentech.wordpress.com/2015/09/19/ff-04-evo-g4-the-2016-ff-test-car-20739548/

This got me properly down the rabbit hole, especially as he pressed two of my particular rc buttons: Tamiya chassis and transmission conversions. He grafted the 4 gear standup transmission from a TRF201 onto his FF04 and subsequent FF2017 custom TRF build. Now you are talking! My experience with designing 3 and 4 gear transmissions for my TRF211 buggy meant i had a good basis to start playing with this idea. 

At the same time, on my clubs fb page people got talking about what we might race if we get an outdoor season this year and a couple mentioned getting fronties. We had a chat about potential rules and settled on the easiest option beibg simply the current 17.5 blinky, open tyres and gearing 10th touring rules, with an encouragement to use frontie bodies instead of race blobs. 

So, a plan forms. Get some updates on my FF03 and design a couple of improved transmission options to see how they go, and eventually get a new frontie race shell. 

Last night i did the first step. TA07 medium stiffness arms for the FF03. I have the same shape TRF419 hard arms on my TA06 and they definitely helped settle the car, but given we'll be outside on asphalt traction is the thing so i went for something a little softer. 

The main reason i went with them is because unlike the reversible arms in the kit, the TA07/TRF419 arms have 3mm offset. Usually this is to the rear. But on the FF03, the shock is driven from the rear of the arms, and the sway bar attachs to the front. 

The big advantage on a frontie is that moving the wheels forward really improves the weight distribution. 

All back together:

The rear arms are basically the same shape as the reversible arms, but a bit stiffer. The shock mount hole is a little further out that the inner hole used on the reversible arms, but not quite as far as the outer hole. 

I got it back together last night but it will need setting up as the forward offset will need slightly more length adding to the turnbuckles to get the camber and toe correct again at the front, and the different shock mount holes on the arms will need the ride height checking. I suspect the front might nees the pushrod tutnbuckles a little longer because the arm hole is a little wider than on the reversible arms. It did jyst still fit my 306 shell, but you can see the offset forwards

As for transmissions, i have been emailing kenneth from kentech to get some advice and been putting together a design for a 4 gear transmission which is massively better weight distribution. Apparently the 4 gear spinning the motor the opposite way really improves traction. 

 

I have limited the size of the spur gear to 69t 48dp and pulled the motor right back against the suspension block, and the layshaft back and down as far as i can. I have some cheap 3D printed clear plastic rapid prototypes ordered to check fit, then i'll get a proper one from Shapeways. 

[ThunderDragonCy]

Well that was successful! Set up the car roughly. 6mm ride height gave no droop at all either end, so a bit of adjustment was needed. This is clearly due to the wider set suspension points. After a bit of head scratching i lengthened the pushrods by 1mm each side so i could get some front droop, and also needed to lengthen the camber links by 1mm to get the camber back to a sensible level. At the rear there were no adjustment options on the chassis so i unscrewed the eyelets on the rods by 2mm per side to get some droop. 

Gave it a quick run at lunchtime and what a difference! The front end is absolutely nailed. Turns in easily and puts the power down cleanly out of corners. It even lets you power out with steering angle. Previously it would understeer on power. 

Its so planted now that the rear was really sketchy! I ended up taking the rear roll bar off which helped a lot, but it could still take more rear grip. To give you an idea of the change previously i had the red soft bar on the front and the medium yellow bar on the rear. Now i have the red front and nothing on the back. 

Later on i did a little more tweaking and put it on race rubber. No additive, but felt like i ought to try and get the setup working on these. Was nice to get some rc driving in. 

 

[ThunderDragonCy]

Been working on this a little more today. The rear was still really bouncy and unsettled, and after yesterday's successful test of my TA06 with much stiffer springs, I've decided to go that way with my FF03 as well. The kit came with white super stiff front, and yellow medium rear, so I went back to that, reset ride height to 5.5mm all round and tried again. It was better. The front was even more planted, but the rear wasn't quite right. It's all a bit of a compromise with the wide set shock mount on the rear arms. I measured up the reversible arms from the kit. You use the wider set of holes, but the inboard option from that choice of two holes. This is 17mm inboard of the upright pin. The TA07/TRF419 arms are only 14mm inboard of the pin, but there are three options for sway bar attachment on the other side. I measured these, and BINGO! the outermost sway bar hole option is 17mm inboard of the pin. I already established when I did the swap that they aren't offset in any way, so I just flipped the arms and moved the shock ball on the arms, and then screwed the shocks back to their stock length. This was MUCH better. As the kit was designed, and more settled at the rear over the bumps. Still a lot of oversteer though. The front really is nailed with these arms! 

I moved the shorty battery from nearly at the front to all the way forward in the battery tray, which helped a bit. Tried the stiffer yellow medium front bar, but I'm not sure if that made it better or worse. Anyway, I looked at my Hudy setup guide and it suggested more angled shocks and lower rear roll centre for more rear grip. As I was doing all this, I realised that all the rear tower fittings are symmetrical. An idea formed, I flipped the arms around again, and flipped the rear tower. Now the arms are the way round they should be, but the shocks are inboard, but better weight distribution. Little thing, but it all helps.

Looks well trick!

And showing the shock mounting hole correct for the FF03 when using TA07/419 arms

Hopefully get to run it tomorrow.

[ThunderDragonCy]

Did a bit of checking manuals, and i had forgotten that i took out the kit spacers from the suspension blocks on the rear. I put then back in which lowers the roll centre further. This combines with the 2mm spacers i put under the inboard balls last night and that is a much lower rear centre, which allow more roll and more grip hopefully. Set it all up with 5.5mm ride height rear, 6mm front for the bumps. 

What a transformation! So much more rear grip. Way more settled, more even grip front to rear. Sooooo much fun to drive! Fully charged my battery and used one of advantage of the lockdown to walk/drive all the way around the block tearing up and down on the main road. It was ace! Really happy. Feeling excited to get it on track at some point. 

Few more things to try out though. Firstly, in the FF03R manual the spacers in the front blocks put some anti dive in. I am intrigued and it's easy to try. 

Second, try higher gearing to something around what the club guys have recommended for 17t brushed. I have the right bits if i borrow from another car. 

Pull the 17.5 brushless race setup out of the TT02 and see how it runs with that. Be interesting to compare driveability to the brushed. 

Finally, slightly longer term (if Covid19 related finances allow) get my 4 gear transmission and test that, and also get a bittydesign HCF race shell and see how that runs.

[Nicadraus]

Nice build! I see you've replaced the suspension arms. I had planned to do that but instead, here's what I did.

I reversed the FR suspension mount. FF remains without any spacers underneath. 

This set up gives the arm extra 2 degree aside from 4 degree angle of the c-hub.

But since you're using separate mounts for the FR, you can try adding spacers to lift it. 

At the rear, both suspension mounts are reversed and I didn't use any spacers. This is to give more droop and suspension arms play upwards.

RF

RR

With 0 degrees angle.

Also, there are two holes at the sides on the battery tray and a bridge with a "canal". Use that to cross wires instead of going around or over the battery for a cleaner look.

The car drives like a charm and handling in corners is really nice where the suspension works great. I've used 30k oil for the gear diff and it's very effective.

The FF-03 is such a fun car to build, tune, and customize. Lots of parts for it too. Hope to see more soon.

[ThunderDragonCy]

@Nicadraus Thanks for the comparisons. At the rear i was running without spacers, but it's definitely better with them in now. I am running on bumpy asphalt so i do need some droop, but not lots. The current setup running 5.5mm ride height seems to handle the bumps just fine.

At the front, you have the flipped block setup from the FF03 R manual, if you have 3mm spacers under there. I measured it up and 1mm spacers under my split blocks will give the same setup, with some anti dive. Keen to try this. I have 500k oil in my diff as that's what it arrived with, but it puts the power down so cleanly now i dont think i will be changing that until i have finished testing all the other things i want to try. 

[Nicadraus]

25 minutes ago, ThunderDragonCy said:

@Nicadraus Thanks for the comparisons. At the rear i was running without spacers, but it's definitely better with them in now. I am running on bumpy asphalt so i do need some droop, but not lots. The current setup running 5.5mm ride height seems to handle the bumps just fine.

At the front, you have the flipped block setup from the FF03 R manual, if you have 3mm spacers under there. I measured it up and 1mm spacers under my split blocks will give the same setup, with some anti dive. Keen to try this. I have 500k oil in my diff as that's what it arrived with, but it puts the power down so cleanly now i dont think i will be changing that until i have finished testing all the other things i want to try. 

Yes. I have exactly the R set up. Because originally in the Pro manual, both front and rear suspension blocks are reversed/flipped. I didn't realize that the R set up was different from the Pro. I only found out after I set up mine and downloaded the R manual, that's when I figured I actually did it right. Haha!

[ThunderDragonCy]

Got the rapid prototype of the 4 gear transmission and did a trial fit. 

The clear blue side was a mistake as the shape isn't very accurate and clearly experienced some shrinkage compared to the white part. Even the white part wasn't good enough to fit bearings, but it's cheap PET material via a treatstock vendor. Cost under a tenner delivered. 

Anyway, loose fitted the diff and layshaft and tried to get it in. Wouldn't really go as its still too tight around the front shock bulkhead interface, and my effort to improve the performance by dropping the diff height didn't quite fit with the moulding in the lower deck. Still, this is why we prototype. 

Here's the view on the layshaft side with a 69t 48dp pinion. 

It is just touching the driveshaft, but to be fair this iteration was designed around a 64t spur, but that would have involved digging it out of the TT02. Also, i have since moved the design on a bit further anyway to raise the layshaft a little bit to clear the 69t, so i thought i would see how this sits. The 64t spur design would have committed me to a FDR of 4.5 which is fine for 17.5 blinky racing, but i wanted to keep the option of slightly lower gearing which left the option for 17t brushed. The current design has space for a 69/32 which is around 5.6 FDR. 

Otherwise, i was pretty happy with it and it is so tiny and low compared to the kit transmission. I got the parts from a treatstock vendor for under a tenner. Excited to get the final version when i have the design dialed. Ken from Cobra said he can make me a motor plate so it's all falling into place. 

Apart from this i used my daily exercise to give it a spin once it was all back together, although i left the 69t 48dp spur on, and paired it with a 31t pinion which dropped the FDR a little but importantly pulled the motor right back in the motor plate slots. Ran really nicely again. Feels like the setup is quite dialed now. My poor 306 shell is pretty battered, so thinking i am going to press the cheap GTR shell i had on the TT02 into service to stop the 306 getting completely destroyed against kerbs. 

 

[ThunderDragonCy]

So i did fit the GTR shell. Had to put the straight body mounts on the rear and move the front body mounts to the front position, but it went on very easily. I can also refit the front bumper. 

Interestingly the car feels way more planted at the rear. Don't know whether it's the silly wing or the lower coupe style body, but it's quite noticeable. 

Today i put some spacers under the front rear suspension blocks to get some anti dive, like it shows in the FF03 R manual. Not sure if it did anything really. Can handled nicely enough, but wasn't a big thing like the spacers back in at the rear to lower the roll centre, or stiffer springs. 

[ThunderDragonCy]

Well, time to press the f**k it button! I've been through the design, measured and re-modelled the internals, checked and double checked. Today I ordered the 4 gear transmission from Shapeways, sent the motor mount drawing to Ken from Cobra Racing and emailed the transmission brace to Fibrelyte. Committed now! Here's how the 4 gear looks:

 

 

Main changes are to the motor plate and the addition of the transmission brace. These will allow me to use the kit FF03 body mounts and also bolt into the front bumper mount. The transmission has offset internals so that the motor is more centred than the regular FF03. With a 3mm motor place and a 2mm carbon brace I can just fit M3 x 50 screws right through the transmission in two places to hold it all together. 

You can see the internals on the see through shot. Nice and compact, with the layshaft as low as I can get it whilst getting the 69t 48dp spur to miss the outdrive and driveshaft. 

The motor plate is traditional style rather than the lower super low two bolt designs on a lot of cars. This is because I want the option of running my 17t brushed motor, and the low 2 bolt designs won't fit on the brushed motors because they don't have enough mounting holes around the can. 

Final view is the transmission without the motor plate, motor or spur gear, so you can see how small it is. The square blocks around the back are rough space envelopes for the FF03 bulkhead interface. It's pretty tight! 

Also ordered to Ride precut slicks that they use for the ETS FWD class. They come on nice spoked wheels instead of boring race discs and I want something to use instead of my Sorex 28s which I want to save for racing. Helps that the Ride's are about the cheapest race rubber you can buy. £20 a set pre-mounted.

[TwistedxSlayer]

This is so so very cool

[Tizer]

If the 4 gear gearbox works out I'd love to get one too! A bunch of guys at my old club drive FF03's and I used to race a borrowed one for a while too. So much fun Need to get my own FWD back together sometime and go race it.

[ThunderDragonCy]

52 minutes ago, Tizer said:

If the 4 gear gearbox works out I'd love to get one too! A bunch of guys at my old club drive FF03's and I used to race a borrowed one for a while too. So much fun Need to get my own FWD back together sometime and go race it.

I'll be keeping this updated. For the standard car i can't recommend the arm upgrade enough. Those flipped front TA07/TRF419 arms transformed the handling of the car. 

If the 4 gear doesn't work i have a super compact three gear sketched out too. I also had a play with a 2 gear yesterday. It's super tight and limited on gearing, but it would be so light and free running. Only work considering if the counter-rotation of the 4 gear motor installation improves the car. The 2 gear rotates the motor the same way.