Building a 1500 bhp BMW G87 M2 xDrive

The BMW G87 M2 is an incredible platform from BMW. With its compact body, S58 engine and ZF 8-speed transmission, the G87 is a tuner's dream. Along with Tom Wrigley Performance, we're building one of the fastest BMWs in the world with upwards of 1500 horsepower and weighing in at around 1500 kg, giving it a perfect 1:1 power-to-weight ratio.

At Texas 2k25 in March, our M2 will compete against the fastest BMWs in the world to showcase the best parts and modifications the aftermarket industry has to offer.

Follow the journey.

The xDrive Conversion

Back in 2022, BMW unveiled the brand new G87 M2 Coupe with the critical information that it would only be available in rear wheel drive, unlike the G80 M3 and G82 M4 that came before it.

Why didn't BMW make an xDrive G87 M2?

As the M2 is BMW's smaller and lighter sports car, it's clear they wanted to stick to their previous M3 philosophy of front engine, rear wheel drive and a vehicle that focuses heavily on driver engagement - we can see this with the M2 now being the only M car that can still be optioned with a manual gearbox here in the UK.

However, we do know a G87 M2 CS is on the way which still has the possibility of having the xDrive drivetrain.

Why convert a BMW G87 M2 to xDrive?

You may be wondering why we are xDrive-swapping an M2 in the first place. Besides, BMW made the G87 to be the smaller, more nimble and engaging driver’s car. Isn’t rear wheel drive the perfect setup?

You'd be right. I mean here in the UK, the weather remains pretty wet for most of the year so an xDrive setup might make the performance more accessible. But, if that's the case, why not just buy a G82 M4 xDrive? Perhaps you just like the smaller package of the M2 - but how could it ever be worth the cost of swapping the entire drivetrain?

BMW G82 M4 xDrive

So, why are we doing this?

We want to build one of the fastest BMWs in the world & we didn't want to chop up our 1000 bhp G80 M3 xDrive after just having it back. The G87 has an additional cool factor as we haven't seen any huge power builds as of yet.

Tom Wrigley Performance Workshop

For those of you who are unaware, we’ve teamed up with Tom Wrigley Performance to turn our Papaya Orange BMW G87 M2 into a 1400 whp+ xDrive-converted monster to take to Texas 2k25 and be competitive amongst some of the fastest BMWs in the world.

If we’re aiming to make this one of the fastest BMWs in the world with upwards of 1400+ bhp, a rear wheel drive layout just couldn’t transfer all that power to the road, especially from a dig in the quarter mile. Rear wheel drive may be okay for 100-200kph/60-130mph times but not drag racing at this level of power.

BMW G87 M2 Stage 2 at Santa Pod Raceway

There’s a lot of work to be done between now and next April including a complete OEM xDrive swap, complete engine & gearbox build with our single-turbo kit and potentially even some custom bodywork and interior modifications.

The xDrive Conversion

As far as we know, we are the first to attempt this conversion on the G87 M2 so, with no blueprint to follow, we're making it up as we go along.

This week, the talented technicians at Tom Wrigley Performance remove the engine and drivetrain so we can assess exactly what parts will be needed and what alterations we need to make to convert the G87 M2 to xDrive.

Now, the way I just said “removed the engine and drivetrain” made it sound like a pretty simple task. For the guys at Tom Wrigley Performance, it’s a very systemised and routine job. However, for the average mechanic that doesn’t have years of BMW main dealer knowledge and experience, it’s no easy feat.

Inspecting the underside

After first getting the car up on the ramp, the underside and drivetrain all looked relatively similar to that of the other G8X vehicles. One thing we noticed straight away was that the propshaft would need to be a fair bit shorter than the one you’d find on a G82. The drive flange on the back of the transmission also appeared to be a different design which would be a hurdle to overcome. The only way to tell for sure was to drop the engine and gearbox out of the car to have a closer look.

Rob, ex-BMW main dealer tech & general BMW wizard, jumped on the computer to make a shopping list of new bits we’d need as well as items that already cross over from rear wheel drive to xDrive cars.

Rob - Technician at Tom Wrigley Performance

Something interesting Rob pointed out from the get-go: the front anti-roll bar is the same on the rear wheel drive M2 and the G82 M4 xDrive. This either means BMW is cost-saving by having only one part number OR this could be a clue that BMW plans on releasing an xDrive version of the M2 in the future, likely the M2 CS. The latter wouldn’t be great for us so we better get cracking and beat BMW to it.

Parts needed to swap a BMW G87 M2 to xDrive

Parts that we needed for the xDrive swap include new front hubs, shocks, suspension arms, drive shafts, a front prop shaft, an xDrive steering rack + arms + track rod ends, steering column, backing plate, front differential, new arch liners with space for the new front driveshafts as well as various sensors and hardware.

In addition to that, we needed a new ZF HP76 gearbox and of course the transfer case for xDrive. We were hoping that we could attach the transfer case onto our existing rear wheel drive gearbox as xDrive cars use the same 8-speed ZF HP76 unit. Unfortunately, the design of the drive flange is different on the rear-wheel drive HP76, meaning you’d either have to modify it or swap the transmission completely. We opted to swap it completely as we already had a complete donor drivetrain from a G82 M4 xDrive. We would then keep the existing mechatronics unit already coded to our G87 and put that into the new gearbox.

Swapping the Mechatronics Unit

To put it simply, we’d be taking the brain (mechatronics unit) from our original rear wheel drive gearbox and putting it in the new xDrive gearbox. The mechatronics is already pre-coded to our car so nothing to worry about on that front. What we will need to code, however, is the transfer case but we’ll cross that bridge at a later date.

In around 90 minutes, the guys at Tom Wrigley Performance had the engine and drivetrain out of the car. They prefer to drop the whole thing out as one unit to make things easier for them.

The engine's out, now what?

With the engine and gearbox now out of the car (yes, we found it quite painful to see our 1 year old G87 M2 in this state), the guys began the xDrive swap along with installing the new front suspension components and giving a few other components a refresh with brand new OEM parts.

The next step for us is to get the new xDrive running gear and engine back in the car and see how many wheels decide to turn. No doubt there will be a serious issue of some description as the conversion has gone a bit too smoothly so far.

Having ‘xDriven’ the front running gear, it was time to get the engine and transmission back in the car and see if we had all four wheels turning. Carefully and precisely, without any swearing at all, the engine and drivetrain were raised back into the car.

With a correct length prop shaft installed, the hardware aspect of the conversion was now complete. All that stood in our way was coding the transfer case to the car’s OEM ECU which required specialist help. As we swapped over the G87’s original mechatronics unit to the new xDrive ZF HP76 xDrive 8-speed transmission, no coding was needed there as the mechatronic was pre-coded to the car. Only the transfer case needed to be coded Huge thank you to our software team as they altered the coding to ensure the dashboard displays all of the xDrive features in addition to the transfer case.

Also, with the engine having been out of the car, we needed to replenish the fluids and prime everything ready first the first start-up. The M2’s S58 engine fired straight up with every warning light imaginable. Once we’d confirmed there were no leaks, the time had come to test whether the swap was successful.

Was the xDrive swap successful?

The G87 pulled away happily under its own power. On the lift, all four wheels were spinning as we shifted up through the gears which was truly amazing to see - the first BMW G87 M2 xDrive.

With the xDrive conversion complete, R44 Performance founder Rhys went to see the car for the first time since sending it away earlier this year. Make sure to check out the video to see his reaction.

The M2 Goes on a Diet

With the xDrive conversion now complete, the next stage of the project is to put the M2 on a serious diet. The G87 weighs in at 1805 kg (3981 lbs) from the factory, meaning she needs to lose over 300 kg to achieve our 1500 kg goal. The xDrive conversion added some weight on top of that figure so the odds are very much stacked against us.

(Once the build is complete, we’ll put it on the scales to confirm the exact number we were able to achieve).

Stripping the Interior

The headlining had already been removed whilst we installed a new xDrive wiring harness but the rest of the interior has to go!

Stripping the interior also makes space for our bespoke SW Motorsports roll cage - an essential for a competition-spec drag car and also to keep us safe when traveling in excess of 200 mph over the half mile. SW Motorsports also installed a few other surprises that we’ll touch on shortly.

Queue the music

After a couple of hours, the interior was fully stripped. Seats, seatbelts, door cards, centre console, carpets and more all in the bin. Well… on eBay as we need to make some money back somehow. The factory carbon bucket seats, for example, sold for around £5,000 which really helps towards the cost of the project.

Installing the Roll Cage

We threw one spare M140i seat we found lying around and drove the car around 2 hours north up to the SW Motorsports HQ. We needed a roll cage and we needed it fast. This project is really against the clock with the car leaving for America in early December. To get a brand new bespoke cage developed and manufactured up to spec can be a very time-consuming process.

Tom Wrigley, who needed the car back for the 1500+ bhp engine build wasn’t best pleased with us for delaying the project.

Fortunately, SW Motorsports are very experienced in the design & manufacture of roll cages and, within moments of arriving at their HQ, the engineers got to work 3D scanning the M2’s interior.

Having previously installed their half cage & rear seat delete kit to our F80 M3 track car, we knew they’d be up to the task. However, a 7 day turnaround would still be a lot to ask for.

Within a week, the cage was inside the car, fully painted & ready to go.

There were a few concerns going in that SW was able to address. Thankfully, the G87 had enough access behind the dashboard to allow them to install the cage without needing to remove it.

Essential for legality, the cage meets regulations with its FIA-specified mountings. The cage uses flush connectors which are as close to a weld as possible without actually welding the cage to the car. This meant it could be painted outside the car as well as removed and reinstalled at any time.

Towards the rear of the cage, SW added a set-back halo bar to be the attachment point for the required racing harnesses.

AST Air Jacks

Midway through the cage development, we received a package from AST Suspension. They sent us their incredible 55mm air jacks and safety stands. This is a really cool modification that would allow us to jack up the car in seconds, negating the need to carry a heavy floor jack with us across America.

Track-side maintenance would be made much easier and well… they’re just cool.

Installing the air jacks wasn’t without its issues. SW had to move the car’s throttle pedal over slightly to accommodate the driver’s side mounting point. And let me remind you, this was all accomplished within a week of dropping off the car. Incredible work.

The Parachute

One of the final drag racing features is the crash bar-mounted parachute. SW Motorsports swapped the extremely heavy OEM rear crash bar with a lightweight titanium version modified with a parachute mounting point.

The M2 is beginning to look very serious and we cannot wait for you to see the final product.

Building The Engine

The next big task was building the engine. People often talk about how the S58 engine is forged from the factory. This is true, all the main internal components - crankshaft, pistons, conrods, camshafts - are all forged parts. However, forging is just a manufacturing process. Design & materials also play a huge role when it comes to strength.

We’ve seen G80 M3s with over 1,000 bhp on a standard engine however, these cars are running on borrowed time. We personally wouldn’t run any higher than 800 bhp on an unbuilt engine, however mapping and how you bring the power in makes a big difference in how much the S58 can tolerate. Our G87 M2 will be making upwards of 1400 wheel-horsepower and there’s no chance the standard engine would survive that level of power and boost.

What Engine Hardware Needs To Be Upgraded?

To make things simple, here is a list of all the internals our S58 is running:

• ARP main studs
• ARP head studs (custom age 625+)
• 5150 AutoSport CPM Carrillo Pro-Xtreme pistons
• 5150 AutoSport CPM Carrillo Pro-Xtreme rods
• 5150 AutoSport Xtreme Duty cylinder sleeves & O-rings
• 5150 AutoSport High-Performance main bearings
• 5150 AutoSport High-Performance rod bearings
• GSC billet S2 camshafts
• GSC beehive valve springs
• GSC STD intake valves
• GSC super alloy exhaust valves
• GSC intake & exhaust valve stem seals

ARP Studs

We used ARP studs on our previous 1,000 bhp G80 M3 build and they’ll be essential for our G87 project. The studs will allow a higher clamping pressure and improve stability and strength. The OEM bolts can move around a bit which puts wear on the bearings and increases the chance of failure.

Pro-Xtreme Pistons & Rods

These components are manufactured by Carrillo but built to 5150 AutoSport’s specifications. The rods take an unbelievable amount of strain, which is why upgrading to a thicker forged aluminum rod is essential. The pistons are also forged aluminum with a different strength-promoting design, as shown in the side-by-side comparison.

Xtreme Duty Cylinder Sleeves & O-Rings

To increase the strength of the block itself, we’re using heavy-duty cylinder sleeves, also from 5150 AutoSport. Installing these required machining, courtesy of SpecJ Motorsport here in the UK. The O-rings that accompany the sleeves pinch the head gasket to the head, allowing us to run high levels of boost without any lift.

GSC Billet Stage 2 Camshafts

These BMW S58 upgraded camshafts from GSC are works of art. In addition to looking amazing, these camshafts are incredibly strong, as proven on Tom Wrigley’s 1500 bhp G80 M3. In addition to being stronger, the GSC stage 2 cams have larger lobes which cause the valves to open further and for longer. The stage 3 camshafts have an even larger lobe duration however, they are largely untested at the moment which is why we’re sticking with the tried and tested S2’s for now.

Here are the exact specifications of the GSC Stage 2 Camshafts:

 

GSC Uprated Valves

In addition to the camshafts, GSC also supplied us with their super alloy valves. Just like the other components, the valves are incredibly strong to ensure the setup copes with high levels of boost and an increased redline. The most notable difference is the design of the head which is also swirl-polished. This increases airflow by 30CFM over the standard valves.

All benefits include:

• Swirl polished heads for smoother airflow over the valve
• Back cut to reduce valve weight for higher RPM, higher boost pressure, and allow for more aggressive cam profiles without increasing valve spring seat pressures
• Valve stems are micro-polished to allow for less oil retention on the stem, which creates less drag on the stem to guide for a smoother motion
• Intake valves are a modified 21-4n stainless
• Valve tips are either hardened or have a stelite wafer tip fused so that the tip is within 5 Rockwell C of the rocker or valve tappet for extended life and less wear
• Valve tip lengths - GSC has taken extra time to adjust tip heights on the applications to require less tipping of the valve, to maintain proper tip height for proper valve train geometry, and to cut down on install times when setting valve lash
• GSC has also adjusted the keeper groove to properly balance intake and exhaust spring pressures to reduce the use of valve spring shims and maximize performance from our spring and retainer kits.

GSC Beehive Valve Springs

To support the valves, we’re running GSC’s oval valve springs with titanium retainers. The ‘beehive’ design means the coils are progressive in size, increasing strength. They also utilise advanced material heat treatment methods for superior load loss capabilities. These springs have the highest level of spring load retention while still maintaining good fatigue throughout the life of the spring. Beehive springs allow for the use of a smaller, lighter retainer allowing for higher RPM and more valve control.

Valve specifications:

• Max RPM: 9,000 RPM
• Max boost: 70 psi
• 101 lbs @ 1.415" install height
• 221lbs @ 0.982" (11mm Valve Lift)

Their primary function is to prevent what’s known as valve float. This is where high levels of boost cause the valves to push open as the spring doesn’t have enough resistance.

GSC Valve Stem Seals

Lastly, GSC Power-Division Viton® valve seals provide improved resistance to high temperatures, fuel, and chemical contaminants as well as extended wear as seen in high rpm engines. These are the last pieces to the puzzle and round up the engine hardware we’re using to achieve over 1500 bhp in our BMW G87 M2’s S58 engine.

Final Modifications

AIR JACKS RAISE THE CAR FOR THE FIRST TIME






Jay from German Auto Werks finalized the air jacks setup and we lifted the car for the first time. The AST and Krontec system works amazingly well however, we discovered the legs were a little bit short for our application. With high-profile drag tires and standard suspension, the car will barely lift off the ground… These air jacks are designed for circuit cars, not drag racing.



AST, being the legends they are, are currently manufacturing some bespoke longer legs to optimize the setup. This will make swapping wheels and tyres at the strip much easier.

INSTALLING THE SINGLE TURBO



After chasing down the DHL delivery driver, we managed to get the Miami Blue Precision 8385 Sportsman single turbo installed on the car. We also got the Miami Blue CSF inlet manifold installed and the two-together look beautiful in the engine bay.






The flange we were waiting on from Florida finally arrived, meaning the car had to travel 3 hours back to Overkill Performance to complete the single-turbo kit ready for tuning.

TILLETT CARBON FIBER M BUCKET SEATS

Now, take a look at these!






These are the new Tillett BMW M carbon fiber bucket seats based on the beloved B10s. Not only do they look incredible with their gloss carbon finish and M tri-colour details but, they also offer much more support by distributing your weight across your lower spine rather than it all being centred on your butt. This means you can relax your lower back muscles instead of using them to constantly hold you in place - better for comfort, endurance and driver engagement.

These seats are coming soon to the R44 Performance online store.

If you have a car with comfort seats and wish you had the factory buckets, these will be a great alternative!

ALPHA N CARBON FIBRE BODY PANELS





As part of our quest to achieve a curb weight of 1500 kg, we picked up a full carbon hood and carbon fenders. They also make the car look very aggressive which is a bonus. The vents in the bonnet are great for cooling and you can even see the Miami Blue Precision turbo peaking through up close.

The Alpha N carbon fenders are also functional, allowing air to escape from the front wheel arches to reduce drag.

RADIUM ENGINEERING FUEL SYSTEM

Following the engine build and single turbo setup, the next challenge was to deliver the necessary fuel required to achieve 1500+ bhp. The OEM fuel pumps are only capable of around 800-1,000 horsepower. You can push them a bit further by upgrading the motors within them - something we do on customer 1,000 horsepower builds.

With the power we’re looking at, an upgrade is essential as we don’t want any limitations from the fuel supply. Lots of drag cars, such as Tom Wrigley’s G80 M3, will delete the fuel tank to save weight and just use a small external tank & swirl pot. As we want this car to still be useable on the road, we’re retaining the OEM tank which feeds the Radium Engineering swirl pot using the OEM fuel pump.





From the swirl pot, we’re running 3 additional fuel pumps. 1 will be run off the ignition and the other 2 will be run off the Motiv for extra fuel pressure when needed (typically over 50% throttle). The fuel then runs out through a filter to the Radium Engineering regulator where we’ll also run an ethanol sensor to determine our current mix. Radium also supplied us with some larger diameter fuel lines to optimize flow.

This build wouldn’t be possible without them so we’d like to say a huge thank you to Radium!

As for the fuel injection, we’re using the OEM setup with uprated Injector Dynamics 2,600cc injectors.

COMPLETING THE CSF COOLING PACKAGE

As you saw previously, we installed the CSF level-up inlet manifold - coated in Miami Blue. To complete the setup we installed the CSF front mount heat exchanger, ZF8 transmission cooler and engine oil cooler.

With the amount of power the M2 will be making, things will get pretty hot under the hood so these CSF upgrades are must-haves!

Alongside the increased cooling capacity and higher quality, one great benefit of CSF is the integrated rock guards to protect the components from road debris. With the front bumper of the G87 being quite open, your OEM radiators are very exposed to damage. One big rock and your car could be in serious trouble.

RUNNING IN THE M2 ON THE DYNO

As with any brand-new engine, it needs some run time to bed in before pushing it too hard. Tom got the car on the dyno for some run-in miles going up and down the rev range, changing through the gears to simulate a typical road driving scenario. This involved putting the car on a base map to make it driveable. With the size of the turbo, Tom couldn’t get the power much lower than 750 bhp for the initial break-in period.

We couldn’t take it on the road just yet due to the windows still missing. The first drive is coming soon!