MF01X Porsche 934 Road Car

[ChrisRx718 4599]

For some strange reason we like to sometimes build projects "just because" and for no other reason other than to see what's possible.

One such event for me was to try and build an AWD M-chassis Drift Car. Tamiya make drift tyres for the M-Chassis with neat little "Tamiya" branding on the tyre walls, part number 54374: 

Now surely they didn't go to the effort of producing them purely for the very expensive and very short-lived TA05-M chassis? Whilst that would make the perfect home for them (because an M-06 can't drift with its heavy backside) I don't have a TA05-M in my collection and given the price of used examples I'm not planning to anytime soon either.

When Tamiya announced the MF-01X I immediately purchased and built a Jimny and in the process of doing so I struck on an idea; this little thing is AWD and M-chassis sized. It'd be great, right?

Wrong. After spending a fortune and building the below model it was obvious that it just didn't want to drift nicely. It could do basic low-speed stuff but as soon as you tried to transition from one direction to another, the heavy motor being right out the back beyond the rear axle just made it like a pendulum and the short chassis made it almost impossible to counter-steer enough. I came to the conclusion that an MF-01X drift car just wouldn't ever work.

Looked cool though, right?

In the meantime I came across a 3Racing TT01 M-chassis conversion kit, documented in the following thread:

https://www.tamiyaclub.com/forum/index.php?/topic/92714-3racing-m-chassis-tt01-conversion/

 

So the MF-01X Drift build languished in a box un-loved for the last 4 years doing nothing. 

As you can see I nicked some bits from it during that time; the front CVDs and the Super Stock TZ went onto other builds. 

Why did I use M3x10 cap-head screws? The honest answer is an accidental order online where I meant to order button-head screws. Not a very exciting reason, but I figured I might as well use the screws now that I had them. They don't look too bad, just a little "different"!

So as per the title of the thread I set out to answer another question that nobody has ever asked; can you build a "usable" budget chassis for Tamiya's lovely Porsche 934 bodyshell?

I mean, even Tamiya didn't get this bit right. The 934 was originally on the 30th Anniversary chassis which was a kind of re-worked TA-05 (and very cool) but ultimately it was un-obtainium for the casual collector and car-park RC car abuser (which is very much me). Veteran users might remember my take on this with the 934 F103GT-S bespoke, shortened-chassis build: 

Likewise, I still haven't finished that build either. The intention was to make use of the Anniversary bodyshell on a chassis which was more useable and less expensive than the 30th Anniversary car, but ultimately that project got mothballed as I realised that even my regular F103GT is a real handful even on super-smooth tennis court surfaces. I will finish it, one day...

Ever since then Tamiya has released the 934 Jägermeister TA02SW on a 236mm chassis. I mean, what? It's a 230mm wheelbase bodyshell. Unacceptable in my eyes, and to the many collectors who had to realise some means of "Wheelbase Fix" for their not-at-all-cheap Tamiya Porsche. I was not a fan and did not part with any money.

But I have since bought 2 more bodyshells and one day, whilst musing and reading @JennyMo's thread on her MF-01X adventures I realised upon some mental arithmetic. 

You can build a 230mm wheelbase MF-01X...

You do need 2x the shortest 15mm chassis connector pieces (Parts B3 & B4) and 1x medium 29mm chassis connector (B8 & B9). Add this to the spacer-less chassis which Jenny built at 171mm Wheelbase and you arrive at 230mm.

 

Screw all of that together and you've got yourself another problem - the propshaft.

That's intended for a 225mm chassis so - rather predictably - it's 5mm too short.

I thought I had purchased a cheap alloy hop-up for the Long Wheelbase MF-01X (239mm) but I had actually picked up another 225mm one. Ah well, my Jimny can make use of that one. 

The idea behind the cheap hop-up was 3-fold;  
- Easier to cut down by 9mm
- Easier to drill a 2mm hole for the cross-pin
- It's blue, therefore it is better

However, due to this unintentional mistake I had to cut-down and drill an original long-wheelbase Steel Propshaft. That stuff is tough. It annihilated a Dremel cutting disc, but the end result was that it fit in the custom-length chassis:

Spot the problem? The hole for the cross-pin is now 5mm out of whack, too (for future reference; the hole has to be 14mm from either end of the prop). Drilling through that steel propshaft destroyed 3 drillbits, it's really tough!

Voila! A working prop. Shame it's not blue. 

That'll do for Part 1. You're probably thinking "Ah, but Chris, whilst the wheelbase is fixed to 230mm the width will still be M-chassis size - and too narrow!" - and you'd be right. But this genius knows no bounds. Just wait and see...

[ChrisRx718 4599]

Finally it's live! 

I can give you a little update on this one.

The next issue I face was widening the track width to suit the 934 body, which is regular touring-car width. RCJaz had these TL01 alloy arms on offer for a ludicrously cheap price, so I bagged them (although I would later regret this decision)

Yeah Racing! TL-01 universals / CVDs for good measure (and they're cheap & reliable- I run them in my monster truck and no trouble so far). I haven't gone mad in this picture and re-fitted the short propshaft, I've just taken pictures at the wrong step...

Before I lopped the arms off I did a quick body check:

Huzzah! If you squint it looks like everything will line up (albeit difficult to see from a single camera perspective - you'll have to take my word for it)

"Tis But a Scratch" - geddit, cos it has no arms?

One thing I thought I had forgotten 3 years prior when I planned this project was that the M-05 hubs the MF-01X uses wouldn't perhaps fit the TL-01 arms. No fear- I had remembered to order some C-Parts back then it turns out. I also found a "Lightly Tuned" motor which I again have no recollection of buying, but the blue motor would suit all the other blue bits on this project to a tee.

Rear arms on:

Now this is tight, even using the Yeah Racing lower arm mount kit which relocates the upper camber link (which I would have zero hope of connecting to with this setup). There's free movement up and down but no longer space to fit the little dust cap which conceals the pinion / spur alignment window. A little bit of tape should suffice anyway - at least that's what I've told myself.

The opposite side has plenty of space for motion. The TRF shocks are definitely overkill, but they do look smart.

Front end next.

[bRIBEGuy 3310]

I mirror your thoughts on the TA05M (a dream that will likely not materialize...), and also think that a M-Chassis drift car would be rad!  I was stoked when the MST RMX-M was announced, but kinda bummed that it only has a 225-245mm wheelbase range (I want dumb and short!).

Your build is great so far.  

[Busdriver 6268]

I’m signed up for this. Glad the mods ok’d it eventually!!!!

[Honza 1088]

MF-01X build became quite popular lately

23 hours ago, ChrisRx718 said:

One thing I thought I had forgotten 3 years prior when I planned this project was that the M-05 hubs the MF-01X uses wouldn't perhaps fit the TL-01 arms. No fear- I had remembered to order some C-Parts back then it turns out

I think this is not an issues, The M05 hubs are more or less the same, but they have smaller holes for the kingpin screws. Plus rears have built in toe-in.

Have you doublechecked the wheelbase with TL01 arms? IIRC, there was ~1,5mm difference with M05 arms compared to TL-01.

Also, it might be too late, but there's another option for wider arms - comical buggy chassis has about 5mm longer arms than TL01

[Badcrumble 4401]

Love it. I have one of these bodies and had great plans for it... until I realised the wheelbase.

I also have another project that requires a custom prop that has at on the shelf for years. I have finally bought a vice for my Dremel to turn it into a pillar drill and now I'm prepped for buying more drill bit and cutting discs!!!

Looking forward to seeing your progress and bringing this creation to life. An MF-01LW?

[ruebiracer 1168]

Cool project, but an M06 can´t be a drifter? Check out this video. Guess the devil is in the detail.

Tamiya M06 beetle drifter

[ChrisRx718 4599]

Onto the front arms, 

This all went together very easily. The only slight problem I can see at the moment is that the front ride height is lower - giving the whole car some forwards-rake (hey, it worked for Red Bull). 

If I fit longer damper bottom ball connectors then they'll be too long. I need an in-between solution, which might mean pulling the shocks apart and rebuilding them with an internal spacer to limit extension. Not sure yet.

The next problem was the steering tie-rods, which were naturally a bit short:

Instead of completely removing the tie-rods and building them shorter, I cheated. I used these low-friction ones left over from my DF02 upgrade, which neatly provided the extra 'reach'. Zero adjustment, just all "by eye" at the moment. 

Quite proud of that, seems to have worked out quite well without any fine tuning just yet!

Notice how I didn't have a complete set of 4 lightweight king pins. Somehow I had 2 spare in my parts box, not sure how that happens when they're sold in 4's!

Slapped some temporary wheels on and a 3Racing M-05 urethane front bumper.

 

Threw in the Lightly Tuned motor with a 19T Pinion for now. Not sure what the speed will be like, might need to revisit that.

Rear width is almost perfect with the 31mm Kawada wheels and Tamiya slicks. Tyres just sit inside the wheel arches - needs more offset on the front.

Wheelbase looking spot-on. Yes, I'm terrible at cutting out wheel arches - I need to remedy this with some sandpaper before paint. 

The idea for the bodyshell is to go with Tamiya Bright Gunmetal PS-63 to try and achieve something like this:

I appreciate the above is a 930 Turbo of a different body style, but it's about as close as I'll get. I also have another set of Fuchs wheel caps to build a set with black centres, you'll see my other Porsche project in the background of the above image which is based on the 934 RSR TT02 body.

All we need now is some warm weather. And the forecast is for snow!

[ThunderDragonCy 8114]

@ChrisRx718 That looks ace! For shock "inbetweening" try the 54871 TRF V parts. They have some +2mm eyelets on the parts tree. I have them on my FF01 to get the droop right

 

[Nikko85 3752]

This looks fantastic. Another build here did a similar thing but used the one-way diff to allow for 4 wheel breaking but RWD, making it even more realistic.

If anyone is slightly interested I've got an STL file that allows you to print a spacer section of the MF01x in any size you could possibly want (over 9 mm) which should allow for any wheelbase you might ever need!

 

[Pylon80 3308]

On 3/5/2023 at 6:29 AM, ruebiracer said:

Cool project, but an M06 can´t be a drifter? Check out this video. Guess the devil is in the detail.

Tamiya M06 beetle drifter

From the original post I gather that the point of building it as an AWD drifter was to have the pleasure of counter steering rather than using a gyro. You can't *practically* do that on a RWD car. And I'm definitely not trying to spark a discussion on whether or not that is possible 😐🙏😅

[ChrisRx718 4599]

Bit more fiddling today;

Changed the front damper rod ends to the long ones from the same sprue. I was pretty certain this would make them still "too long". 

Faced with this conundrum I decided to add the little 3mm internal spacer and that meant dismantling the shocks and changing the oil. Fun times. But the result was worth the mess:

Spaced version on the top, un-spaced on the bottom. 

Proof is in the pudding, left-hand is spaced and right-hand isn't. Sorted.

Looks "level enough" for me; certainly it's lost that Red Bull F1 forward rake it had going on before.

Next I started fitting the magnetic body mounts. With an un-drilled bodyshell it seems a shame to start making holes. I'm a big fan of these magnetic body mounts but I've never fitted any in their "intended" manner, I always dismantle them and fix them more rigidly to the chassis. Front end:

Rear end is going to be tricky. Using the stock locations the magnets would be slap in the middle of the rear window - we can't be having that. I've mounted them on the rear suspension pickup points for now, but will have to wait for some, ahem, 60mm screws from eBay to arrive 

Front end looks decent. Now please don't comment on the state of my arches, no I didn't cut the bodyshell out with my teeth, I'm just out of practice.

Time to do some sanding and masking ready for paint...