When 3 Rotors & 1 Turbo Aren’t Enough:</br> RADBUL Gets 26B-TT Power
Quad Power In The House

Imagine, if you will, your ultimate no holds barred race car. What would it be and what sort of numbers would it be making? Then imagine having the tenacity to actually make it happen in the real world and be able to watch it metamorphosis from a bare shell in front of your eyes. That’s got to be cool, right? For Speedhunters own Mad Mike Whiddett, it’s something he doesn’t have to think about, because it’s exactly what’s happening right now in an immaculate industrial unit on Auckland’s east side.

If you’ve been following the progress of Project RADBUL, you’ll already know that Mike and his team are pulling out all the stops with this build; taking what they’ve collectively learnt from years of local New Zealand and international pro drift competition, to create what is destined to become one of the wildest pro drift machines ever seen.


Since our last RADBUL update a few weeks ago, things have been moving very quickly in the Townsend Brotherz Racing (TBR) compound. In that time I’ve ventured out to the workshop a few times to catch up with Kaz – the project’s technical lead – and Mike, and chart the progress. On each occasion the magnitude of this build has become even more evident. As I’m sure you’ve already figured out from the title of this post though, there’s been a pretty major change to the grand plan – something that can now be revealed.


Right off the drawing board a 20B three-rotor motor similar in specification to the monster-bridgeported and Garrett GTX45 equipped engine that powers Mike’s BADBUL Mazda RX-8 was slated for the new chassis. With a switch to E85 ethanol fuel and a few more power-producing upgrades, Kiwi rotary engine builder Pulse Performance Race Engineering (PPRE) was confident they’d reach four-figure output numbers. One thousand horsepower in an NC-chassis Mazda MX-5 that should tip the scales in race trim at 1,000kg – you don’t even need to do the math to figure out how insane that would have been.


But the 20B is out the window. Count those rotor housings and you’ll understand why… one, two, three, four. A dummy-block for test-fitting this might be, but yes – a custom-built PPRE 26B is headed RADBUL’s way and it’ll come packing not one, but two Turbo By Garrett turbochargers.


Mike puts the change of thinking down to his recent visit to the Goodwood Festival of Speed. MADBUL was one of stars of the show, and that’s something that Mike largely attributes to its unique naturally aspirated four-rotor engine. Quite simply, for this ultimate build nothing else was going to cut it in RADBUL, and with Warren from PPRE crewing on the RX-7 in the UK, the decision was made then and there to shelve the planned 20B build and concentrate on a 26B package.


The only thing that was standing in the way of the idea was how well the longer engine would fit in the NC’s engine bay. The limiting factor was the firewall, which to meet pro drifting regulations cannot be cut-out or shifted rearward, and therefore dictates where the engine can be positioned. The latter is a very important aspect when it comes to weight distribution in relation to handling, but as you can see here, there’s not going to be any problems. In fact, by design of the MX-5’s factory recessed firewall, the four-rotor 26B block will sit further back in this chassis than the three-rotor 20B does in the RX-8. You could almost consider it meant to be…


That said, space around the rear rotor housing is limited, something which will reflect in the design of the custom PPRE intake manifold. Kaz will be looking after the exhaust manifold and positioning of the Garrett twins and their boost-controlling Turbosmart ancillaries.


The 26B upgrade is not about needing more power, because a lack of performance was never in question. As I eluded to in the introduction to this project, 1,000hp/1,000kg provides the same power-to-weight ratio as the Peugeot 208 T16 that Sébastien Loeb destroyed the Pikes Peak International Hill Climb record with last year. And that was a machine built for outright acceleration and speed with drive running through all four wheels – not a little rear-wheel drive MX-5 built to slide. That said, Mike is just a little bit excited with the prospect of an engine that’ll generate around 1,200hp on its low boost setting. This is all kinds of crazy.


With those sort of numbers on the way, the strength and reliability of a driveline to support it is now more important than ever. But as the attached Holinger RD6 gearbox suggests, there was never going to be any concessions made in this department. The Australian-engineered six-speed sequential transmission is a proven piece of hardware and should have no problems standing up to all the abuse that the 26B and Mike can throw at it. With compact dimensions and a weight of just 39kg it’s helping the handling cause too.


For the rear end it’s a case of sticking with what they know and the same bulletproof Winters Performance differential that’s used in the RX-8. And once again, Autosport Dynamics (ASD) in Charlotte, North Carolina were tasked with setting it up for the application. We’ll take a closer look at this component in the next update after it’s been adapted into the MX-5’s rear subframe and had its custom-made, large-spline axles from The Driveshaft Shop (also out of North Carolina) fitted.

Serious Cooling Required

From a performance and reliability standpoint, another very important piece in this puzzle is the cooling system. Like Holinger, PWR is an Australian company that’s recently come onboard with Mike and is lending its experience to Project RADBUL. Given its large dimensions, the custom designed and fabricated air-to-air intercooler that consumes the front end of the MX-5 should keep the intake charge nice and cool.


A big intercooler doesn’t leave much space for anything else up front, but that’s okay because the plan was always to relocate the radiator into the rear and shift some more weight over the rear axle anyway.


And that’s exactly what’s been done with the custom PWR unit that stretches across the entire breadth of the boot. Or where the boot once was, anyway.


Bearing in mind that RADBUL will be mostly sideways when it’s driven in anger, custom-designed ducts on both sides of the car will direct airflow across the radiator’s expansive core, where a pair of SPAL fans on the underside will help draw it through. Using a hinge mounting system on the forward-facing side and mounting bars with rose-jointed ends at the rear, Kaz has made the rake angle that the radiator sits at totally adjustable too.


The other PWR cooling product being employed – this time straight out of the catalogue though – is the oil cooler. Unlike a common air-to-oil unit, this compact device is cooled by water and gets fitted inline between the engine and radiator. The result is high heat transfer with low pressure drop.


Because the cooler doesn’t require air to flow over it, it can be fitted anywhere in the car. Given the nature of drifting it was a no-brainer to position it well out of harm’s way.


So for the oil cooler, the remote oil filter fitting and the reservoir tank for the engine’s dry sump system, the passenger side front footwell was chosen as the ideal mounting location.


While the 26B block test fitting, driveline, and cooling system work has all being going on, Kaz has also found the time to tick a few more items off his long custom fabrication list. The front crash bar which he designed using CAD has come out looking really nice. But you didn’t expect anything less from this guy, right?


And other things, like finding the optimum position for the pedal box have been determined too.


I’m already due back out at TBR to capture the next round of progress, and we’ll be bringing you that update in the just a few weeks time. Work on the suspension and steering systems is now well underway, and with the arrival of a bunch more parts there’ll be plenty to show you. In the meantime, we’ll leave you with this final image of the Mazda – now sporting a rather large rear wing…

And a brand new The Making Of RADBUL clip from Red Bull.

Brad Lord



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This thing is madder than you Mike! Will soon find out at least! Cant wait to see this beast in action! Stoked!


Your my hero!! ✊


4-rotor twin turbo , now that's insane !


If this is competing in FD USA I will have a hard time waiting to see this in person. Here's hoping for many embarrassments of piston engines!! haha Calling this a quality build would be putting this very lightly...too siked


I think the kaimai's is calling you mike


Video & last image show it have 6666 on the spoiler stand , is that the same 6666 as Rocket Bunny ?


I'm not really into drifting, but I really enjoy the development that goes into some of these cars. Their using a lot of not so everyday systems, and helping to make some outrageously strong products.


ssonosk Thanks, I enjoy and appreciate many forms of motorsport - not sick of drift yet though!


RDS Yep that's the one!


RDS Garrett have supplied the goods!


senaua hahahaha well you might be right! so pumped to fire it up


Are you expecting 1000hp to the wheels ?


You expecting a 1000hp to the wheels. ?


Andyrew shut it down you reckon?  conquer the kaimais


http://youtu.be/VkFqJh-zGfk Race to the Sky. Just do it.


2 much cuzzy keep up the good work show them waht nz rotangs have to offer one of my drifting idols in nz along side the fanga nd gazzy


Keep a eye out for a SS VE ute 26bTT coming out in the GC Bro, gonna be more of a show car tho.


The day Mad Mike makes a terrible car he should name it the "SADbull" but Mike just keeps making awesome cars over and over again so i do not see it happening lol 


Will you ever bring back the rx8?? I miss that car :(


That rear wing doe.




Whow!!! Crazy. Wanna come to the workshop to see it in real life!!!! Keep rotary rockin Mike!!!!


OMG this makes me wet. This thing is basically a bike. 1kg=1 hp


As I alluded* to
allude: to hint
elude: to evade


Man this is insane. That car is gonna toss you around with all that power. 
Question though MadMike Whiddett, for a guy looking to give rotaries a try is there any points I should know before diving into it? Rotaries are just one type that I haven't had any experiences with...yet.


This build make the Gatebil volvos look like barbie and kens..  ;)
Cant wait to the next uppgrade, this buil is of the charts. Thumbs up!

Gianluca FairladyZ

Wow... This is unbelievable! It is such an art to build a well designed race car! MadMike Whiddett  What intake design will you use for the 26B Engine? Will it be the telescopical pipe desing like in the 787B Le Mans Racer? When you add more Rotors (besides more power that you get) does the caracteristic of the power curve change or is it just like always, but more powerful? Thx


This is a very interesting build to watch,but I must ask. Why put 1200hp in a chassis that is... different compared to most vehicles that have been used for competitive drifting? Is it one of those 'why not' ideas or is there a reason to compete the US in this versus bringing BADBUL back to the states?


You can't add the telescopic intake because this is a turbo application. Plus, Using the intakes would not have fit anyways.
I suspect this will be a Bridgeport.


MadMike Whiddett RDS so does this mean the possibility of another rocketbunny/ madmike body kit for an nc?


can't wait to see end result.
Speedhunters anyway i can purchase that SH jacket?


No longer living in the land of the long white cloud, but damn proud of what we can achieve and this is going to be off-tap.

Looking forward to seeing it in action!


Had to answer the phone so i paused the vid, came out pretty good if you ask me:


@zz Gianluca FairladyZ yeah I thinkt it will be bridgeport too, helps keep some torque(pp style is more suited for peak power) and keep it drivable. Adding rotors does effect the power curve; the added cc's will give some more torque next to obviously lifting the powercurve by some amount.


kphillips9936 MadMike Whiddett Haha yes Johns build is insane! I'll be paying him a visit soon :)


Good luck Mike. Please make another note to Mazda management for keeping the spirit alive with rotary engines and RWD cars.


love the fact that you stick with rotary engines!


That video should be removed due to the pornographic adult content featured in it.  Transmission, drive shaft, and AW oil cooler.. unf!


Fck those autoplay videos.


thanks for the autoplay feature my office thanks you guys for that crap


When I first saw the MADBull i thought it was crazy "4 rotors NA engine, wow it brings back memories", if you know what I mean..Then I saw BADBull and that was even more insane but this MX-5... I don't know... This is a whole new level of craziness "1200 hp with low boost", that's not something you hear every day for sure.Next car i want you to use the PPRE six rotors they slammed in the RX4!


This is gonna be so f**** cool man


Danny George and Mad Mike holding it down for Mazda !!!! Would love to see those 2 cars compete against each other.


Sick as bro! This thing will be mental on the track! Especially when running 1200rwhp! Great work Mike! Love to see what the finished product will look like!


Awesome car and very cool build but I really love how you did this spotlight. You did the normal pictures, and so on, BUT you included a video that seems more like it was made for the fans. It wasn't some interview (which in my opinion only satisfy someone else) this talked about the car like it was one on one. You guys could start to do videos like this with some of your cars so you can get an idea of what the person who owns the car is actually like, passionate, crazy, speed freak, whatever. You know?


I wonder if this is actually an NC or will this coincide with the new NC Miata


Good to hear dude, I wanted to showcase the entire build from start to finish to the fans so you could all see the development, build process and why we use specific parts. Thanks to Red Bull for making this production for you viewers. Enjoy


Thanks! We too can't wait to unleash the beast.


Hey you're in luck, search MADMIKE 6rotor RX4 on YouTube and you will find vids of me shredding it at WTAC 2013.


Rotang all day everyday! Munch munch pistons for lunch!


Don't need to tell me that, I am pushing Mazda hard and they are very passionate about the strong feedback since they signed with me. Epic things to come.


Probably one of my better photos thanks. Glad you pushed pause.


Thanks we are putting everything we know into this build.


I think it is very important to keep the show alive in drifting hence why we battle and challenge ourselves with these 'different' builds and to build the most explosive packages for the fans is only natural for my team.


Thanks I am confident our team and partners have the best knowledge available put together to make this thing one hell of a MX5. @zz is correct as we are running a twin turbo setup the telescopic throttle bodies won't work. TBR are currently fabricating the manifolds so they will be on episode3.


Yep she will be a very violent car to drive. We run all genuine Mazda parts inside our motors, we have proven these to be the best with all my cars screaming over the globe, I will also say a strong rotary comes down to the builder and the tune.


Thanks! Yep my BADBUL RX8 will be back out in force next month dude.


Hehe it might not take you to a Top Model audition but who knows, ill send it in and hope for the best! Ill keep you updated.
On topic though, if you want to reveal it that is, what weight distribution are you aiming for?


When this thing is done, you guys should totally make a double car article with RadBul and the other 20B NC Miata track car which is currently being built in Australia. These would make some epic material!


any future plans to drop 16x (still in development)?


Sorry neffgordon, we don't have these for sale right now, but perhaps something else from our store might appeal to you? http://store.speedhunters.com/ Cheers.


Sweet baby Jesus! It's "parts Christmas" up in that fruity little bitch!


Looking sooo sick! side comment Speedhunters please don't have videos autoplay, some of us are supposed to be working hahaha


MadMike Whiddett Thanks for sharing, the clips are sweet :)


MadMike Whiddett Love sexy fab work, insight (if it isn't secret stuff) to the though process and compromises when designing the intake would have me even more glued to this.


MadMike Whiddett  That's very good news indeed mate!


Whats gonna happen with your car situation you gonna use the MX5 for domestic or international and same with the mad and badbull ?


you guys REALLY need a copy editor.


MadMike Whiddett I am absolutely love the video that included in these article , there's also a video included in previous article too , and I love that one too ! What I really like the video is , sometime I don't really understand what you meant (well , my English is bad) , I watch the video & there it goes ! Good job on the video !


MadMike Whiddett RDS Garrett , this brand of turbo seems familiar in drift car ; oh yeah , both turbo the same size ? or one big one small ?