canyoncarver

@Pylon80 apologies if I slightly digress from the core discussion of this build, but what dampers are those? For my 45th 934 I managed to get hold of a set of gold 53280 low friction dampers but they ended up costing me quite a lot. All in all, they look fantastic and were worth it for my black and gold themed 45th chassis but I don’t want to pay that kind of money again for my upcoming TA02 SW restoration project of an ex runner I found for a reasonable price online. This chassis will get a 934 body but with a Rothhams livery.

Hi, Can you provoke the noise by adding some resistance to the drive train, eg run it on your bench and hold one of the rear wheels at the time?

The custom YR lower arms have the ball on the inside of the arm, which might be hard to drill, but I should be able to use my Tamiya hand drill to drill a hole on the outside and then tap it like you suggested. Need to check the geometry but if it works we should be in business. Thanks for your advice. Great to hear your confirmation of that Type S conversion can be take off the table.

Quick update on the upgrades I received from Tamico yesterday : Spool, DCJs, Cups all went in beautifully. I made some cushions for the bearings out of aluminum foil, so the front drive line is now very tight and precise with some minimal slop. It was expensive but the build quality is there. Whether this upgrade was worth it, time at the track will tell. Will post photos. I am thinking of writing down a little build thread but I'm really busy so we'll see. A few hiccups with the YR stabilizer It doesn't come with a manual, but you can find the manual online for the entire Yeah Racing competition set online, where you see the instructions for the stabilizer Rear goes in perfectly and the links attach well to the lower arm with the help of a Tamiya ball end on each side Front arms have no balls or holes for screw where you can attach a ball end so currently I am stuck. @Pylon80, @skom25 - any ideas on how to best solve this? When I ordered it, did not understand that the YR stabilizer set is actually specifically developed for the $180 YR competition set that comes with its own arms that do have balls. Other than that the quality of the stabilizer set is excellent. Aluminum mount, ball raced, easy access to adjustability etc. It really feels like a quality product but I need to solve the front link attachment before I can say anything about how overall handling improves. Simplest solve would be to switch to TT02S front suspension but that is probably quite expensive and might throw front/rear balance off and I certainly don't want to go down the rabbit hole of rebuilding my TT02 into a TT02S or SRX. Definitely not worth the money. RC-Kleinram mentions that your TT02 can be modified to make it work so there has to be a way I did take a short test drive in our living room and it seems to have done wonders for the roll in the rear and the steering feels more direct already. Very promising if I can hack the front links.

There are much more qualified TC members that can truly elaborate on this, but in short my understanding is : A front spool helps you get power down quickly out of the corner Saves weight from the drivetrain, which you can either save or reallocate strategically with weights Weight distribution in a car really deserves its own topic but loosely : some add the equivalent of the saved weight back into the lower parts of the front when running a spool to truly get the most traction and steering out of it. The disadvantage of a spool is that it can reduce the amount of initial steering of the car as opposed to a diff as both front wheels rotate at the same rate. This delta decreases of course the more you stiffen up your front diff. A spool also adds more stress to your front drive train as everything is truly locked, which is why you need the dual cardon joints (fancier universals). The DCJ also help reduce the chatter that a fully locked spool produces. My understanding is that also you have to also expect more/faster wear because of the full lock. The difference between almost locked and locked is in my understanding small if you pack your gear diff with really heavy oil (like 500k, 1m or 3m). The main difference is that a spool is locked forever whereas an oil gear diff packed with heavy oil can always be cleaned and refilled with a less heavy oil. So you have more options to try and see what works best for you. You can also put the oil gear diff in the back if you one day decide for a spool in the front, which will further improve your car. The opposite doesn't work unless you want to get into drifting. I thought about this a lot for this very reason but decided for spool at the end of the day. Also, it removes a key tuning parameter which focuses me on improving my tuning skills of the others. The effect on traction and handling will be increasingly similar the more you stiffen up the diff (two different ways to achieve almost the same thing) Many argue that the slight give that an oil gear diff with heavy oil still has, adds less stress to the rest of your front drive train than a fully locked. In theory this is 100% correct but how it actually plays out for you in practice is likely very personal depending on driving style, how heavy oil you put in, grip of track, quality of components in your drive train, how powerful motor you run etc. What I am saying is that if you would try both options in your car as a real world A/B experiment, the difference in time to replace a key component (e.g. swing shafts) might be negligible or not depending on your own unique situation. I am not worried about this and neither is the vast majority of the focused racing community. Me crashing is a statistically a much bigger threat to the life of the front driveline than the spool vs stiff diff delta Some argue that a diff with heavy oil doesn't require DCJs the way a spool does, but again some split opinions there. My own logic is that the heavier oil your run, the closer you get to a locked diff, the more it behaves like a fully locked diff, the more similar requirements/wear and tear on the rest of the drive line. With 500k, you might get away with no DCJs, with 1m or 3m, you might not. Also, my dogbanes started to fall out all the time when I stiffened up my front diff with AW grease so struggle to imagine how a TT02 with a diff that's stiffened up with 1M oil or diff putty would even be drivable without DCJs. Others might have a different experience based on driving style though. On low grip, ball diffs are typically seen as better as they have built in slip by design. A ball diff also locks up in a smoother and more linear fashion than a gear diff and makes the power/car easier to control in corners, which is especially important in loose conditions. There are endless threads on the pros and cons of gear and ball diffs on most rc forums though. I've found the debate a bit like the never-ending manual vs PDK discussion in the Porsche 911 forums on Rennlist As mentioned above, I am sure others have plenty of insights to add. Maybe even some corrections

With the XV02 spool + SRX TT02 cups, you need the 33mm shafts. With the 22049 Oil Gear Diff, the 37mm are the ones to go for. So if you have the 37mm shafts and the M Chassis axels, an oil gear diff will be your cheapest path. It also introduces some adjustability as you can drop super heavy oil into it, almost locking the diff, or have something less stiff. I started with stock TT02 and decided to try out the spool as our track is high friction carpet (club dominated by XRAY X4s and Pan Cars).

@skom25 I’m with you on the price. It’s a lot for it really is but the dog bones were flying all over the place and I had no universals to take from another car. Anyway… here’s the list of parts listed from the diff to the hubs : SRX/XV02 Direct Front Coupling, 22047 SRX Direct Cup Joints, 22064 The ones for the XV02 you get with 22047 apparently fail on the TT02 geometry so Tamiya released this “upgrade” with the SRX. You’re really just paying twice for the same cups only one pair works and the other one breaks 33mm swing shafts, 54969 as the TT02 cups are longer and therefor require the shorter shafts TRF417 Cross Joint Set, 51444 M-Chassis Axles and Rings, 54623 I’ll assemble everything tonight with one of our boys and post some pictures so that you can see how it comes together. The slightly annoying thing is that cool looking spool will remain hidden under that ugly ABS cover so it’s tempting to look for cover delete options out of the KrV5.1 master piece by @wtcc5 but that takes expense to a whole new level so will try to resist that thought. My goal is to add the carbon towers, camber links as per @Pylon80 design, carbon top deck and carbon bearing cover for the rear shaft bearing so that I can delete the heavy and ugly spur gear / pinion cover. At that point I need to stop investing into the TT02. It should be a great drivers car at that point and a great car to develop on for our middle son. It’s really fun - and addictive - to upgrade TT02s but once I’ve done the above the money is better spent on a used X-RAY X4 … or a (hopefully) TRF421 based 50th Porsche 934

Crap, you’re right. I don’t how I missed that when I upgraded to the hardened grey parts half a year ago. OK, that’s good news. Would you mind posting a photo of your final camber link setup?

OK, you just reminded me that I had my dampers attached to the lower hole as per the TT02 manual So I shifted all 4 dampers to the upper hole, which gave me 3mm and gets me into reasonable territory. As the Carbon Towers are the entry ticket to a nice adjustable camber solution, I will likely still fit them further down the road. I am planning to also eventually get a carbon top deck and the carbon cover for the rear bearing so that I can loose the ugly and heavy spur gear / pinion cover, completing this TT02 journey. At that point I am probably at a used XRAY X4 from 2022 or so but driving, upgrading and tweaking the TT02 has been a great and fun journey. I drive it at the local track together with our 4 year old so it's also very much a bonding thing (or so we explain the hop ups to my wife ). Tomorrow we'll install the SRX front coupling together. Also, our dark green 911 RSR body with 934 Black MCI gold decals gets a lot of praise at the club, which our 4 yo really enjoys as he's a big Porsche fan. I'll post photos of the YR Stablizer Set install for sure. I haven't seen ANY reviews of it so it was a bit of a leap of faith but stabilizers seem to have done wonders for TT02S's here on TC, so hopefully this YR version works great too.

5mm standoff : great! Ride height / Carbon Towers : Got it, you finally solved this mystery for me. Yeah, 10mm is a disaster. Awesome, then I'm clear on the next mod after my current upgrade of the front coupling & cups & universals + YR stabilizer set.... Thinking about it all this now, I might actually introduce carpet roll with the stabilizer set if I also don't drop the ride height by upgrading to the carbon towers...

@skom25 FWIW, I gave up on the stock front diff (and the dog bones that were constantly falling out on the track once I had stiffened up my front diff with AW grease) and ordered the new XV02 spool / direct coupling + the upgraded outdrives + the shafts and universals. I also ordered the Yeah Racing stabilizer set. Was expensive at $30 though. Am truly curious to see how the car will go through corners with all of these upgrades on. Package from Tamico arriving tomorrow

Lol, we all get each other in trouble.. Just to make sure I am tracking : You put the 5mm standoff through the aluminum cups in the Carbon II towers to get down to 3mm for the screw right? Also, I am still struggling to get my TT02 down to 6mm with the 42102, currently around 10mm, which is too high for our local carpet track. I am on the Plastic Damper Towers though. Any tips?

Hi @skom25 Where did your TT02 end up in terms of ride height? My TT02 has the 42102 TRF Special Dampers, which I believe are 55mm. Trying to avoid the financial wormhole that @Pylon80 referred to above, but would love to get rid of those plastic upper arms and install a set of turnbuckles for camber like you. thanks

@wtcc5, I was more thinking as inspiration for the curvaceous Egress body, but you clearly came up with an amazing looking combo with the gold and black 👌

It looks amazing. Maybe draw inspiration from Mechanic After Hours DB01 RRR?

What a great build. Those golden knuckles set it off for sure. I think you would enjoy building the Optima Mid 87 a lot too

Love your build; very inspiring ! GL with racing it How did you manufacture the carbon components?

Those are both good tips! Thank you Anyway, back to @wtcc5's amazing build. Do you see any obvious ways of stiffening upp the chassis or is it simply better suited for low/mid friction tracks?

Oh... so TA08R might not be it for me as our very nice local track is high-grip. The KRv5 is a masterpiece and certainly tempting, but XRAYs are the dominating class at our club so much easier to get racing. TT02 will probably get off the ground soon, but likely very restricted. The TA05MS based 934 is also wonderful so the thought of building a runner from an old TA05MS keeps on haunting me, but the wheel base will certainly be a big penalty and it's easily a €700-800 excersice for a car with rare spare parts, but I do love it. Not exactly a logical line of thought Our conversation triggered some dangerous thoughts so yesterday I was checking out XRAY X4 and Tamiya body specs and it turns out that the new 911 GT3 body should fit the X4 pretty well. The wheel base is 215 vs 256 on the XRAY but that should still be workable. This move might offend two RC communities in one move but would certainly be cool with a truly great body on a focused track car. I know why modern TC bodies look the way they look, but they do absolutely nothing for me so maybe I'll just race with style instead. It's not like Porsche aero is horrible Interesting to learn about your TA03 experience. I have been trying to find a 47443 Porsche GT1 TA03R-S for a reasonable price (it feels like I missed all the great kits when away from the hobby). Again an older platform though so hopping it up might get X4 level expensive. Somewhat digressing from the core topic, but I am in the finishing phase of building a hopped up version of the already very hopped up Kyosho Optima Mid 87 60th. This will be a runner for sure. What a build, absolutely loved it and so curious about how it will drive.

@wtcc5 fantastic build and story telling (one of your many) and excellent body choice! I am very curious to hear your thoughts on how she drives. After 35 years away from the hobby I got a TT02 911 RSR that I’m enjoying tweaking and tinkering with, but with €150 of hop-ups in, I’m at a point where I’m trying to figure out how much more to tweak it vs just saving up for a more focused track car. Most people at my local track drive XRAYs but I’m drawn to the TRF 420 or the TA08R. Also, I’m a sucker for Porsche bodies so trying to find a platform that would still work with one even if that penalizes my aero. I’m toying with the idea of building a 30th Anniversary runner from a TA05 MS but it has a 230mm wheel base and maybe running a car based on a platform that old isn’t that smart considering it’s getting hard to get hold of some parts. My 45th 934 lives a comfortable life on the shelf and my 30th is still NIB but will get built on day (just missing carbon battery holder). My fingers are crossed for a TRF421 based 50th Anniversary

Thanks for sharing this - very helpful! Waiting for some parts before I can continue my build but I’m very excited about running this epic buggy

Great news on the under tray front. I was just in contact with Steve at Penguin and ordered two undertrays for the 87 body. He asked me to simply order the optima mid undertray on eBay and mention in the comment that I want the 87 version. Very seamless, but you might still want to ping him in advance and check availability. Back to the build

Lol. I’ve been down the same path. First I wanted to paint up a Turbo Mid Body for my 87 but the peppermint has grown on me so now I’m trying to figure out a good tray solution for the kit body instead. Late 80s/early 90s are back 😂

Hi @0836whimper I am considering the same setup for the ‘87 I’m building. Did you keep the std pinion? If no, what pinion did you go for instead? thanks

@Anthroxoid, yes totally. I never can get that quote feature to work as I intended. Apologies! Thanks for letting me know the route you’re taking with the body/underbody. Do you think the the Turbo Optima underbody from Penguin would be close enough to do the job together with the 87 Optima Pro body? Thanks for the tip on Marwan! I’ve heard his name many times but never took the time to check out his product. A set of OT66 would look awesome on the shelf, between runs Marwan sells an Optima Mid underbody too but seem too short to cover the entire carbon deck. Penguin’s Optima Mid underbody seems to be doing a better job of that. The build is otherwise amazing. Waiting for the rear CVDs and the stabilizer to show up in the mail before I carry on