I’ve been on a 1:18 Acceleracers binge lately with my recent builds, and I’ve really only been focusing on Hot Wheels original fantasy designs since that makes up the bread and butter of the series’ vehicle cast, but there are in fact plenty of iconic real-world licensed designs from the series that deserve some love. I’ve also really only been building cars from the TEKU team – time to switch it up finally show the Metal Maniacs some love!
Taro’s ’70 Roadrunner is a carryover from the World Race, the same way Slingshot and Deora II were in Ignition. Unlike Deora II and Slingshot, the Roadrunner actually received some more mechanical and cosmetic changes to it that go beyond just a different paintjob and colored windows – it’s got a giant blower sticking out the hood now, along with quad side exit exhausts, and of course some iconic 5-spoke Torq Thrust-style wheels.
Going through Ignition frame by frame, Taro’s Roadrunner really doesn’t get much of any meaningful screentime – especially compared to Deora II and Slingshot which were much more prominently featured before they were destroyed. Maybe because it’s a licensed vehicle instead of a Hot Wheels original design?
I’m going with the Acceleracers version of the car for this build mostly because the livery is extremely simple and much easier to create and design, instead of the more complex Scorchers livery from the World Race. It’s really just some generic black and red flames along the flanks of the car and a couple of Metal Maniac logos.
The nice thing about licensed real-world cars is that there’s usually no shortage of scale models produced for them in large scales – unlike Hot Wheels original designs like Slingshot & Power Rage, where I have to create those bodies from scratch. In this case, we’re using a high-end 1:18 ’70 Roadrunner model from GMP.
The base model alone was over $150, but that’s about average for high-end 1:18 models, even cheaper than some AutoArts I’ve bought in the past. Apparently this is a limited edition run, with only 780 produced. I’m sure what I’ll be doing to it is sacrilege to some diehard collectors.
I knew the model came with opening panels and an engine, but I didn’t realize it was this chock-full of gimmicks and features when I bought it. There’s a rotating driveshaft and opening glove box?! That’s pretty next level even for these premium 1:18 models – I’ve never had an AutoArt with either of those features.
Sure feels premium. There’s a plastic GMP logo diamond holding the Styrofoam closed and it opens up like a fancy sarcophagus.
So apparently this Road Runner is a “Street Fighter 440 Six Pack.” I’m entirely ignorant on American cars so I have no idea what that means or what makes this different than a standard ’70 Road Runner.
Interior is very nicely detailed. The steering wheel does technically turn and is attached to the front axle so it moves the front wheels, but only a couple of degrees. Just moving the steering wheel alone isn’t enough to turn the axles all the way to full lock.
Trunk features flocked lining, a whole spare wheel, and a battery with wires running into the cabin! Incredible amount of detail for a mass produced model.
I have no idea what motor this is, just that it’s a carbureted V8. True to what’s advertised on the box, it is indeed very well detailed and “fully plumbed”.
Undercarriage. It’s so fascinating to me coming from someone who’s really only owned and worked on modern foreign cars to see what’s underneath these old domestic cars. I always thought leaf springs were exclusively a truck thing, so seeing them on a performance car like this really throws me for a loop. I guess turn-down exhausts were also common in muscle cars of this era?
Anyway, time to start taking this thing apart – like most diecast models, the chassis is secured to the diecast body with some phillips head screws in the corners of the underbody, but GMP really went out of their way to sell this as a premium model by even including screw cap covers that hide the phillips heads! Took me a minute to realize those little circles in the corners were the screws, since when you initially turn the car over there aren’t any obvious attachment points. I had to pry the black plastic circle caps out of the recessed screw holes with an Exacto knife to gain access to the actual screw heads. I’ve never seen any model company go this far on their underbodies.
Before I separated the chassis from the body, I opted to remove the rear subframe first – if this can even be called a subframe? It’s really just the differential connected via the axles to the rear leaf springs and driveshaft. They separate with just push-out pins holding the leaf springs in place. The driveshaft and shocks slide right out.
The rear wheels pop right out of their axles, and behind them GMP even included brake lines coming off the calipers! You really would never be able to see this level of detail behind the wheels anyway, and I don’t even go this far when I’m building my own handbuilt stuff. Insane to see.
With four phillips screws in each corner removed, the body shell slides right off. The dashboard is attached to the body rather than the chassis, but the rest of the interior is left behind.
Closer look at the trunk with the full sized wheel, which is secured with a single phillips screw from the underside. The carpet lining is actually a sort of fabric carpet rather than being flocked.
Real fabric seatbelts are included for both the front and rear seats because safety first. It’s amusing to me seeing so much extra length underneath the interior tub after I removed it.
Closer look at the engine bay. This motor ironically will be coming out and will be entirely replaced as part of this build. Plus, I have to repaint the engine bay black anyways.
The front wheels were significantly more difficult to remove than the rears. I couldn’t see any obvious way to remove them just looking at the stock assembly, and there wasn’t a screw holding the wheel in place underneath the center cap, so I had to resort to more uncivilized methods: I just drilled the center of the wheel from the outside until it came apart. Yes, this destroys the original wheel, but we were never planning on keeping those anyways.
With the wheels off, I could start pulling the actual motor. Starting by popping the firewall off, which was just held in by a few pegs and a bit of glue. The firewall itself is plastic, with the master cylinder and brake booster as the only separate parts on it – the rest of the detail like the windshield wiper motor is molded into the firewall.
Thankfully most of the engine was just lightly glued in, so some light tugging got most of the stuff like the radiator hoses and accessories out. The block itself was only held in by one screw at the bottom of the front subframe that went into the oil pan. I’m surprised it wasn’t genuinely mounted with scale motor mounts, given the level of detail in the rest of this model.
For the replacement motor, again, I have no idea what I’m doing when it comes to American motors, nor do I know anything about the heritage of classic muscle car V8s. I literally went to Texas 3D Customs and found the engine set I thought matched Taro’s giant blower motor the best from the movies – in this case, it’s apparently a Gen 1 Firepower Hemi motor with a bugcatcher up top.
Texas 3D Customs has a large catalogue of resin parts on their site, but what they seem to do best is engines – their catalogue is second to none, and the resin quality of the parts themselves are very nice and crisp. I’m not sure if they develop these models in-house or not, but the motor comes together very easily and precisely, even without assembly instructions. I probably struggled more than most since I’m really never around v8s, even as a car enthusiast.
Engine parts painted up. Nothing too fancy, but I tried to make an effort to use different shades of silvers and mist bits of gold for the headers and oil pan, just so it doesn’t look like one giant monotone silver and black lump.
Assembled sans headers. I’m really not sure if the headers will fit in the bay at this point lol.
The main chassis is metal, so there really isn’t much flex or give here when it comes to fitting the motor – I preemptively cut out a bit of the transmission tunnel just because I expect that area to bind the most when trying to drop the motor in. Plus, the section I cut out had a screw mounting point that only went in with the original transmission – we won’t be using that, so better to remove it altogether to create more room.
Initial fitting is…rough, to say the least. I haven’t cut or grinded any part of the bay yet besides the transmission tunnel slice, but as it sits, the motor is sitting too high and too far back – as you can see, the distributor is having a cozy time with the windshield wiper motor and pushing the firewall backwards.
The crazy thing is, the Firepower motor isn’t even significantly larger than the 440 or whatever that came out of the car originally. The main difference seems to be the much wider valve covers – I’m not really sure why that is? I’ve read that Hemi motors supposedly have much more complex valvetrains than standard engines, so maybe that’s it?
The main areas where the motor is coming into contact with the bay are the lower subframe brace and the shock towers. The subframe brace isn’t really an issue – I can grind that thing down all live-long day and you’d never notice, but I really wanted to avoid grinding too much of the shock towers off, especially since the suspension control arms are actually attached right behind them, and the real shocks do unironically run up into the towers. If I ground them down too much to make room for the giant valve covers on the motor, we’re soon not going to have anything left for the front suspension to attach to.
It may be hard to tell from this angle, but the fitment is now significantly better. What I don’t like is that to achieve this I’m essentially wedging the motor between the shock towers, but hey – needs must. We’ll just have to run solid poly engine mounts to mitigate engine lash, yes?
Making onee more notch in the lower subframe brace so I can push the oil pan up against it jussttt a bit further.
Yeah there’s absolutely no room down there to fit the headers that came with the Firepower motor lmao. I might end up cannibalizing the low-profile factory-spec headers off the original 440 engine to squeeze ’em in there instead.
Who needs motor mounts when you can just wedge your valve covers up against the shock towers?!
Test fit with the body on and hood open – thankfully the motor is laying flat and the hood does clear, even with the giant bugcatcher up top! I dread having to cut the hood open and actually fit the top of the motor through though…
Another slight problem with mounting the bigger motor and barely squeezing it in the frame though: there is now not enough room in front of the engine to mount the original radiator. Thankfully there’s a bit of space between the front frame and the bumper once the body slides over – I just had to grind down a bit of the bracing.
The original radiator sat just behind that front frame section, right in front of the belt pulleys, but the new Firepower motor has an oil pump(?) sticking out of it right where the radiator would go, and this is about as far back as I can mount the engine before it starts making love to the firewall, so the radiator really has to be relocated.
The one that came with the model originally is a bit fat, and plus it had a built-in fan shroud on the backside, so it wouldn’t fit being mounted in the slim space between the front bumper and front frame, as shown here.
The solution is then of course, we need a new slim-pro radiator. TK Diecast would’ve been perfect for this since they make universal 1/18 radiators, but with the current tariff situation still railing us in the states, it’s not the most economical to order much from international waters anymore. Enter a random eBay seller from the midwest who had a collection of random 1/18 radiators for sale for about $10.
I have no idea what model this one was originally off of, but to Hell with it – it works! Don’t ask me how I’m going to run the coolant piping to the engine, I haven’t thought that far yet.
With the motor fitment itself figured out, it was now time to see how we’d be able to squeeze the headers in. As it is, you can see they sit way too low, and is making contact with the oil filter(?) and the steering tie rod.
At one point I really considered using the stock-style exhaust manifolds off the original 440 engine, but I just couldn’t bring myself to do it – I really wanted to make these hot rod looking headers work, dammit.
In the end my solution was to just keep chopping stuff off that the headers were colliding with until it fit – this include pretty much deleting the original flanges that actually mated to the motor in order to shorten the tubes from the top, allowing the entire assembly to sit further up and away from the steering tie rod. But hey – it fits now!
For all that work chopping bits of the underside of the headers and motor up to fit it, you can’t even see those fancy hot rod headers at all from the top of the motor, thanks to the giant valve heads. Well, I’ll know they’re there.
Anyway, with the hardest part of fitting the motor mostly done, back to disassembly of the main body shell: the trunk is held in place via its hinges by these two black plastic tabs, that thankfully come right out with the removal of the screws holding them in.
Headliner is one solid plastic piece that pops right off the roof. I didn’t even notice this before disassembly – the visor covers actually move! Entirely unnecessary and borderline pointless for a scale car model like this, but damn if it isn’t just a neat little detail.
These doors are nuts. I head no idea how they accomplished the windows rolling up and down mechanism with the actual window crank turning the windows, so seeing the engineering firsthand underneath the door cards was fascinating. The more annoying part is that these door cards didn’t just pop off on pegs.
So…I get using screw covers to achieve a cleaner look for parts that have to be held together with screws, like the body-to-chassis connection, but…the door cards?! C’mon guys, two screws to keep the door cards held on is overkill. Is this the sort of thing only someone who would disassemble a $200 limited edition collector’s model would whine about? Absolutely. Do I still wish they just held the door cards on with press-fit pegs like literally every other manufacturer (including AutoArt?). Yes yes.
Mind you, if the screw covers were easy to remove and gain access to the Phillips heads underneath, I wouldn’t be bitching and whining – but the problem is, these things were damn near welded in, and I didn’t have any good insertion points to gain leverage to pop them out. One of them runs right through the silver trim on the door card too, it feels totally unnecessary to sacrifice a clean door card for this.
Anyway, with the door card finally removed, here’s a lovely closeup of how the window mechanisms actually look underneath. Two main gears are connected directly to the door, with pegs on them that link into slots at the bottom of the clear plastic window, which push it up or down as the main gears turn. The main gears are then connected to a tiny plastic gear that’s linked to the actual window handle lever. As someone who’s struggled just designing opening doors from scratch, this is the sort of compact, basic engineering that I wish I had the means to develop on my own.
While most of the plastic parts on the doors come off with screws or pegs, the little quarter windows and their plastic bezels are actually held on by metal rivets. Guess they ran out of screws at the factory? Either way, these can be drilled right out for removal.
The chrome trim on the front edge of the bumper is plastic, and pops right off with a bit of force – there’s also a soft foam-like strip glued in near the leading edge of the bottom of the hood, which can be pried off.
These lovely and almost overengineered hood hinges are also connected to the hood with rivets, which we’ll have to drill out.
Front and rear chrome bumper assembles can all be pushed out from the inside via their plastic tabs and pegs. Same goes for the front and rear light assemblies.
Interestingly, the front wheel wells have these little black plastic blanking plates that are lightly held in by glue – I assume they’re only there to fill the gap from the engine bay and the body shell, so you don’t end up seeing through the wheel wells to the ground with the hood open?
Finally, removal of the front and rear windshields, along with their accompanying chrome edge trim. I do really enjoy how all the chrome is actually separate plastic parts, instead of chrome paint on the body shell – this will save me so much time and effort having to re-chrome things after paint.
I have to double check the entire body to make sure I didn’t miss any little bits and bobs that may still be plastic – after all, the paint stripper I’m going to be using on the body parts will melt and eat plastic real quick. Luckily I remembered to pry off these little flank intake bits, that are separate plastic pieces which peg into the main body.
This was by far the most effort I’ve had to expend stripping a die-cast model body down to only metal components – damn near every piece felt like it had an inordinate amount of plastic trim and bits and bobs that all had to be carefully disassembled or drilled out.
Finally, we’ve arrived at the acid bath!
Stripped to bare metal.
With the body parts all stripped down, we can start thinking about the hard part: cutting out the opening in the metal hood for the big ‘ol blower to stick through.
Upon a little further research, I actually found that GMP makes a bunch of variations of the ’70 Roadrunner – there’s a version floating out there with an actual blower sticking through the hood, though it’s much smaller than what I’m running here with the Firepower. Still, that means there’s a version of this casting that has a cut hood, which I assume is what the vaguely blower-shaped indent is on the underside?
My supercharger is a bit longer and fatter, so I’m not following that indent shape on the bottom exactly – I’m going to start with a rectangle first just to get the basic area down. I’m making these cuts with a metal Dremel cutoff wheel, so it isn’t the most elegant or precise process, but it’ll work to get our desired results.
Check out how thick that hood metal is! No wonder why it took forever to grind through.
Overall looking good – I’ve eyeballed the size and location of the hole up until now, to find out unsurprisingly that I’ve come up just slightly short. I’ll need a bit more space up front to get the pulley through, plus I’ll have to widen the front anyway to fit the bugcatcher.
Very precise measurements, trust.
I really wanted to keep the opening as tight as possible – it should look deliberately shaped to clearance the supercharger, not just be a random hole in the hood with giant gaps on every side that looks like it was haphazardly opened up.
I like to think I achieved that? I’m honestly shocked the hood closes and lined up as well as it does, especially considering that I completely eyeballed the first half of these cuts.
From bright yellow to deep glossy black. This is done with 3 coats of Tamiya’s TS-14 Black lacquer spray paint – you really get a lovely deep glassy gloss right out of the can with this color.
As per usual, the livery decals for this build are printed at scale by TK Diecast, via their custom decal printing service. Normally I’d commission them to redesign or draw up stuff like this for me from scratch, but the Maniac Roadrunner livery was basic enough that even a monkey like me could put it together in Photoshop. The flames are literally ‘shopped together from a stock flame image I picked out on Google, with some basic Gradient and Stroke effects applied.
The most tedious part of this process was having to cut each bit of the flame out by hand with an Exacto knife.
Like most of my custom decals and liveries, this stuff has never been done before at this scale, so I’m really sizing everything based on my best guesses and approximations. For this design especially I was agonizing over whether or not I should oversize it slightly to give me room for run-off in case the Roadrunner body was slightly longer than expected.
It’s not 100% accurate to how the livery looked in-film (especially the front fender area, the flames should be a bit higher), but regardless I think the look is unmistakably Taro’s Roadrunner, and I really like the vibrant red against the black body contrast.
Moving onto finishing touches for the motor while the clear coat on the body cures. I’m using cheap (literally, it says $.98 right there!) 18 gauge craft wire to wire up the spark plug wires from the distributor.
It’s actually really neat to be able to do this, since I typically work only with modern tuner-style engines, most of which obviously have computer controlled electronic ignition, so I’ve never actually even had a chance to even wire a distributor before.
Throwing a splash of clear red paint onto the bugcatcher for that iconic look.
For wheels, we’re obviously not sticking with the original star-shaped black wheels that came with the 440 pack – enter some classic Torq Thrusts, a classic American muscle staple. I had grabbed a free 3D model of these wheels online that a buddy was able to print for me in resin in a staggered set.
We were able to print matching hard resin tires, but I do happen to have a set of spare real rubber tires that do fit – I’m leaning a bit more towards those instead.
Plus, I didn’t realize when we were printing them but the front wheels came out weirdly thin. I know this could probably be fine as a classic American muscle thing with their thin front bicycle tire look, but I’d really rather prefer the more even tire width look.
Rough test fit with the rubber tires. I think this works!
I did have an extra wheel printed that I’ll stick in the trunk as per the original model having a spare back there – I don’t mind keeping this one with the hard resin tire – it’s a spare after all.
I absolutely could have just glued the brake calipers to the rotors and glued those directly to my wheel hubs and onto the chassis as I usually do with most of my static model builds, but for such a detailed model with so many features I figured it would be a real crime not to go maximum effort and make an attempt to keep the spinning wheels. As such, enter TK Diecast’s proprietary resin spinning hub system – those little beige hubs are specifically designed for 1/18 applications to allow rolling aftermarket wheels.
The front of the hub will slot into the back faces of my Torq Thrusts, with the brake disk rotor sandwiched in between. This will effectively join the wheel face and brake rotor together into one assembly and allow them to spin together, while the back of the hub is glued to the chassis and remains free-spinning.
I did have to grind down the chassis attachment points significantly before attaching the hubs, since my wheels have so much negative offset that they’re pushed out too far normally.
Keeping the original brake rotors and calipers – this setup allows the wheels to spin along with the rotors, while the calipers are attached to the knuckles, just like on a real car.
Finally onto some of the minor interior mods – I’m really not changing much here – just hitting the more major recognizable parts of Taro’s interior, like the iconic chain link steering wheel. I was surprised to find a 3D model of this online that my buddy could also resin print for me, I didn’t think these would be common or popular enough for that.
Also changing out the shifter – funnily enough, I poured through Ignition to see if the shift knob was ever actually shown, but couldn’t find an actual shot of it – Taro’s always either shown with his hand over it or it’s cut just out of frame. However, the Virtual Car Gallery (that was a DVD bonus feature in Ignition) specifically mentions that the car has a “skull grip shifter”, which ironically was shown in World Race.
Anyway, all that is to say, the skull grip shifter is canon, and I’m making sure to replicate it here with a tiny resin printed skull that I grabbed off Cults3D. The original shifter was a long twisted chrome thing, with a wood grain decal for the actual knob. That whole thing is going in the bin in favor of our metal af skull shifter.
In pouring over Ignition to check for any other interior details I missed though, I realized…Taro has a whole ass roll cage in the Roadrunner by the events of Ignition lol. This completely did not register for me at all before this. I was not planning on having to build a roll cage, but how could I call myself an Accelenerd if I didn’t? Thankfully the base GMP model already had a roll bar with an integrated harness bar installed behind the seats, so I could use that as my starting point to build the rest of my cage around.
I’m no stranger to building full cages – I just don’t like doing it since it’s always such a delicate and tedious process to make sure everything is cut to precise lengths and kept together with the tiniest dabs of glue. In this case, I’m just building a basic cross section out that will go into the rear seats, but I’m not going to bother with door bars or running the front bars all the way through the dash.
Since the whole thing kept falling apart on me, I’m resorting to some mildly ghetto tricks – drilling out micro-holes in the styrene piping to insert paperclip rods that will act as pin pegs to hold the cage together while the glue cures. I never had this luxury with my 1/24 scale roll cages before since the rods I was using in that scale were too small to pin, but in 1/18 scale they’re thankfully thick enough that I can actually get a pin vise in there.
Et voila! You know, for what was supposed to be a simple and quick build, I feel like this one ended up taking way longer than it should have…
MODE FULL OPEN!
I’m really proud of the hood cutout work for this giant motor and how I was able to still retain the functionality of it all, even if I still barely know what I’m looking at as far as domestic engines go.
The chain link steering wheel and skull shifter are so iconic for Taro, methinks. The skull is literally just pegged into a thin styrene pipe that’s then shoved into the shifter console, nothing fancy here. Ironically, the gauges on the dash are technically inaccurate to how Taro’s gauges looked in Ignition (he had a one-piece horizontal cluster instead of the classic circle pods), but I didn’t think something that minor mattered enough to warrant changing.
Spare tire and battery in the trunk! Ironically the trunk used to stay up on its own out of the box, but I guess I stripped it a little too well, since it won’t stay open on its own anymore, and now requires a prop to keep it up.
Ironically, there are certainly some willing inaccuracies – for one, the Ignition model clearly has the lower trunk bezel and taillight surround in chrome, like the rear bumper, but I decided to just keep mine all black around the taillights. Part of it was just me being lazy and figuring no one else except me who’s poured over the reference material and every single frame of the film would notice this detail, and part of it was that I was afraid too much chrome would make it look tacky.
Taro’s grille in the movie is also clearly different, with vertical chrome slats instead of a traditional mesh. This one, I deliberately kept stock, since I genuinely think the black mesh grille looks miles better and more realistic than chrome slats.
I was afraid for a while that I had undersized the front wheels a bit too much, but I did want them noticeably smaller than the rears in order to achieve that iconic muscle car rake. Thankfully it seems like I just barely got away with it, since the side exit exhaust pipes are damn near touching the ground with the current clearance.
Speaking of those side exit pipes – they were very much the last pieces to go on the car, and with absolutely no fanfare or complex attachment mechanism. They are literally just resin printed pipes that are bent at a 90 degree angle and glued straight to the bottom of the chassis. Do they actually attach to the engine headers I worked so hard to keep? Does it matter when you’ll never be under the car to find out? 🙂
Something that does kind of annoy me is how the roll cage bars in the side windows aren’t straight and parallel with the window frame and roof line, but what can ya do – it’s just a byproduct of them mounting too high off the original roll bar, and having to curve downwards inside the cabin towards the A-pillars. I never claimed to be great at building roll cages anyway.
I know I’ll never beat the stanceboi allegations (not that I’ll ever deny them), but ok for this one, the front camber really wasn’t intentional. It kind of just happened naturally as I was grinding down the front hubs to fit the wheels – turns out with such deep dishes that it really was necessary to get a little tilty up there to tuck the top of the tires under the front fenders.
Paired with a 1/64 custom built by the legendary Zed32 Customs! Because sometimes even I don’t like to build my own cars.
Some bonus shots – our legendary World Race team leaders! Rest in pieces, Kadeem & Banjee.
Something something pass you.
