The BMW E36 is an awesome car that allows for a lot of fun builds. It's a popular pick for a budget-friendly track car as we examined in our E36 track guide. The M50 and M52 engines also allow plenty of potential with the right upgrades. Whether you're looking for a modest 400hp or insane 1,000+ horsepower build a turbo kit will get the job done. In this guide, we discuss BMW E36 turbo kits along with cost, supporting upgrades, risks, and more.
M50 & M52 Turbo Upgrades Background
Before diving into the bulk of the details it's important to discuss some background of the M50 and M52 inline-6 engines. Most E36 turbo kits will fit all years, models, and engines. However, there are a few important differences that affect strength. Block design, rotating assembly, and heads are some of those major topics.
E36 Engine Block Design
BMW M50: Cast Iron
BMW M52: Cast Iron (US) or Aluminum
All M50 engines use a strong cast iron engine block. The two variants of the block are the M50B20 and M50B25. They're both iron but the smaller 2.0L engine has an 80mm bore vs 84mm for the 2.5L M50B25. Sadly, the 2.0 liter engine cannot be easily or reliably bored to 84mm.
The M52 block design gets interesting. Most M52 engines outside the United States are a weaker but much lighter aluminum block with Nikasil coated liners. In the US, BMW opted for a cast iron design on the M52 engine. This is likely due to the higher sulfur in US fuels.
However, Z3 models in the US do use an aluminum block for weight savings. The M52TU from 1999+ also uses an aluminum block. Regardless, most M52 engines in America are cast iron blocks which offer great strength when adding boost.
BMW M50 & M52 Rotating Assembly
Rotating assembly is one of the first weaknesses with the BMW M50 and M52 engines. Around 450-550 horsepower is where rods, pistons, and ring lands become a concern. It's best to stick with lower boost and keep under 500hp unless you're opting for forged rods and pistons at the least.
OEM rod bearings on the M50 and M52 are good even at higher power. However, with the age of the E36 you might consider replacing the rod bearings. Going with new OEM bearings is a reasonable option or you can choose to upgrade.
E36 Cylinder Heads & Valve Covers
Most heads are interchangeable between the M50 and M52. They all share the same basic casting but there are valvetrain differences inside the cylinder head. Also, the early M50 is non-VANOS while the later M50B25TU uses single VANOS. The M52 is single VANOS, too. Love it or hate it - variable valve timing can help reduce turbo lag with proper tuning.
Anyway, the cylinder heads are all solid internally. However, the head gasket is a known issue when adding boost to the E36. You can likely get away with a stock gasket at very low boost and keeping under 400hp. We recommend upgrading the head gasket as one of the first mods after an E36 turbo kit, though. This Athena-SCE cut-ring gasket is a great choice. You'll also want to upgrade to head studs.
Valve covers aren't a concern on the M50 thanks to the magnesium design. Some early M52's are also magnesium, but most valve covers were plastic. Top-mount E36 turbo kits are known to start burning thru the plastic cover on the M52. You can wrap the downpipe, install a heatshield, or upgrade the valve cover as the most bulletproof option.
How Much Power Can a Turbo E36 Handle?
This is a loaded question that doesn't really have a perfect answer. However, E36 turbo engines should hold up to about 450-500whp with just head studs and a cut-ring head gasket. With a great standalone ECU/tuning and quality fueling (race gas or E85) you can squeeze out another 50-100whp pretty safely.
Detonation is the real issue as the M50 and M52 ring lands aren't very tolerant. One bad detonation may also bend a rod or crack the piston. As such, forged rods and pistons are a good idea if you want to safely and reliably push more than 500whp.
Again, this isn't a perfect science. Some M50 and M52 engines may hold 600+whp for the long-term and others may let go well before 500whp. Understand the risks of pushing those limits and decide whether you're willing to take that risk or spend $2,000 on forged rods and pistons up front.
BMW E36 Turbo Kit Supporting Mods
E36 turbo kits should come with at least the basics to get the turbo fully installed. This will include the turbo, wastegate, downpipe, manifold, intercooler, piping, oil + coolant lines, and hardware. Some kits may not include an intercooler as they aren't totally necessary on lower boost & power builds. However, we highly recommend using an intercooler with any E36 turbo setup.
The list doesn't completely stop there. Again, most kits include the basics to get the turbo ready to go. Not all E36 turbo kits include engine management/tuning, fueling mods, and other necessary upgrades to support to newfound power.
We'll move on and discuss the best E36 turbo upgrades in a moment, and some of these kits are 100% complete setups. However, certain kits don't include these components so it's important to lay out the supporting mods you may need.
E36 Engine Management / Tuning
The M50 engine uses OBD1 protocol which does allow the DME (BMW's term for the ECU) to be tuned for boost. However, fault code and data-logging information is rather limited. If you're shooting for 500+whp then we advise moving to an upgraded ECU like the Link G4+.
M52 engines use OBD2 which allows for better logging and info reports. It's a suitable DME for most E36 turbo builds, and there isn't much need to upgrade. That said, an upgraded ECU can still offer better control and safety. If you're looking to build a crazy 700+ horsepower turbo E36 then it's a good idea to upgrade.
RK Tunes, TRM, and several others are great tuning options for the M50 and M52 engines. If you need a complete solution including fueling and MAF then RK Tunes is a great choice. Their tuning package is $1,600 but includes the MAF, upgraded injectors, & wiring harness adapter.
M50/M52 Fueling Upgrades for Turbo Kits
E36 fuel injectors and a fuel pump are the two primary fueling mods for running boost. 60lb injectors will support up to roughly 600whp and 80lb injectors are good for 800whp. If you plan to run E85 then you might even consider 115lb injectors, which will support up to 900whp on E85.
Popular fuel pump upgrades are the Walbro 255, 460, or 525. The DW300, 400, and 440 pumps are also good choices.
Otherwise, the fuel pressure regulator is fine stock. There are gauges on some upgraded ones which can be helpful, but not absolutely necessary. The fuel rail and lines are good to 700+whp, so don't worry about those upgrades unless you're shooting for massive power.
Other E36 Turbo Supporting Mods
Once you knock out the turbo kit, fueling, and tuning then your E36 turbo is essentially ready to go. However, there are still endless supporting mods you may consider. We won't spend much time here since it varies a lot depending on your goals.
If you're building a 500-600+whp E36 turbo then good luck putting the power down. You'll likely need some chassis and wheel/tire mods to put the power to the ground. Additionally, cooling mods and other upgrades can be important for higher power.
While the turbo kits might not be much more expensive for 800+whp just remember all the other goodies add up quickly. Anyway, most E36 owners looking for a modest setup shouldn't need to many supporting mods beyond the turbo kit, tuning, and fueling.
Best E36 Turbo Kit Upgrades
With much of the basics out of the way it's time to move onto some of the best BMW E36 turbo upgrade kits. Please note - this is far from an exhaustive list. There may also be some good used E36 turbo kits that you can pick up. Unfortunately, the options on the market aren't quite as extensive as they were 10-15 years ago.
Our goal here is to include a blend of E36 turbo kits for different budgets and goals. Keep in mind - you get what you pay for and extremely cheap kits (like found on Ebay) usually are not a good choice. Anyway, let's jump in and look at some of the best M50 and M52 turbo kits. As a quick note - this list is in no particular order.
1) CES Motorsport BMW E36 Turbo System
Buy Here: CES Motorsport Garrett GT35R Turbo Kits
First up is the CES Motorsport turbo system for the BMW E36. The price tag is likely going to scare some away considering it's not far off the value of most non-M E36's today. However, this is a very complete and high-quality kit with tons of add-on options.
This E36 turbo kit includes all the basics along with spark plugs, a Walbro fuel pump, and fuel injectors. Then there are options to go with higher flow fuel pumps, injectors, a more powerful Garrett turbo, and plenty of extras.
Careful adding too much to the package otherwise you can easily end up with a $10,000 turbo kit. Still, this is one of few high-quality, complete solutions available today. With the right Garrett turbo these E36 turbo kits are capable of 500-800+whp. Sometimes you have to pay to play (especially with the big boys) and this turbo system is exactly that.
2) E36 CX Racing Top Mount Turbo Kit
Price: $2,157.76 ($1,902.76 w/o turbo)
Buy Here: CX Racing E36 Turbo Upgrade
The CX Racing top mount turbo kit is an interesting option mostly because it's much cheaper than other E36 kits. It may not be significantly higher quality than a typical eBay kit, but at least CX Racing is in the US. The turbocharger itself is our biggest concern. However, if the turbo does fail you could pick up something from Garrett, Precision, or any other large turbo manufacturer and bolt it to this kit.
You can also opt to purchase the kit without the turbo or wastegate and save $255. A quality turbo is going to run about $1,000-1,500 alone so that will bring the cost closer to the $3k ballpark. That still makes for a solid deal, though.
Ultimately, if you're shooting for bigger power builds then this probably isn't the right pick. It might make sense for those looking for modest 300-450whp builds. The downpipe is only 2.5" which is pretty small, so some parts would likely require upgrading if you really wanted bigger power out of this kit.
3) TRM OBD2 E36 Turbo Kit
Price: $6,999.95 - 8,499.95
Buy Here: TRM Turbo Kit
As you likely noticed, this is another quite expensive E36 turbo kit. The TRM kit is highly tested and proven on the E36 and is an excellent, high-quality turbo kit. They offer three different Garrett turbo options: the GT30, GT35, and GT40. Stick with the smaller GT30 for a modest 300-400whp setup that delivers great spool and low-end torque.
Those with bigger power goals can slot in the middle with the GT35 or go for the GT40, which can easily meet any 650-750+whp goals. The larger turbo options do command higher prices, though.
Anyway, this TRM E36 turbo kit is a very complete option. It includes a quality TiAL BOV and wastegate, Siemens Deka injectors, the MAF upgrade, along with their OBD2 tuning. The only thing that's really missing is the fuel pump. The price might be tough to swallow but if you're willing to pay for a top-tier E36 turbo kit then look no further.
4) Custom Turbo Upgrade Options
Given the age of the E36 it isn't as easy to find full turbo kits as it was 10-15 years ago. Even back then, opting for a custom setup wasn't unpopular. This route does take some research and in-depth understanding, so ensure you know what you're doing before going this route.
All of the turbo kit accessories can be pieced together or possibly machined/built by local shops. For example, you can find an awesome E36 top-mount manifold from VI Engineered for $1,650. Tons of other great manifolds are out there for individual purchase too.
Universal intercoolers generally fit the E36 pretty well. You then just need to source a turbo, downpipe, and all the other hardware and accessories. Again, this route isn't for everyone but you can definitely end up with an awesome turbo kit by piecing your own stuff together.
BMW E36 Turbo Guide Summary
E36's are popular builds now days for many good reasons. The E36 is relatively inexpensive and easy to source; though, they are getting harder and harder to come by. It's also an awesome chassis for anything from track builds to E36 turbo builds.
Both the M50 and M52 - especially with the cast iron blocks - are stout engines with good power potential. Most E36 engines can handle 450-500whp with just head studs and a cut-ring head gasket. However, pushing more power safely does require upgrading the rods and pistons.
TRM and CES offer some great E36 turbo kits, but they are fairly expensive. Nonetheless, you have to pay to play and these turbo upgrades are the real deal. Those on a tighter budget can opt for the CX Racing kit, which is a compelling option for modest 300-400whp builds.
Otherwise, you can try piecing together your own turbo kit to end up with a high-quality setup while saving a bit of change. Simply make sure you're confident in your understanding of turbo systems before going this route. Regardless of the specific choice, the E36 is an awesome platform that offers tons of potential with turbo upgrades.
What's your experience with E36 turbo kits? Are you considering one?
Leave a comment and let us know!