Super Street Network

Due to the EU’s Global Data Protection Regulation, our website is currently unavailable to visitors from most European countries. We apologize for this inconvenience and encourage you to visit for the latest on new cars, car reviews and news, concept cars and auto show coverage, awards and much more.MOTORTREND.COM
 |   |   |  2008 BMW 135I - Got Meth?
Subscribe to the Free

2008 BMW 135I - Got Meth?

Getting the most bang for your buck with the BMW N54 motor using water/methanol injection.

Greg Emmerson
Jul 11, 2011
Eurp 1107 01+2008 bmw+135 cover Photo 1/5   |   2008 BMW 135I - Got Meth?

For decades, many of us have followed the same practice with project cars. Typically, the first parts we pick up are an intake and exhaust. However, performance software became a hugely popular mod, particularly with turbo engines such as VW’s 1.8T. The total cost of these upgrades could reach $2000, while power typically increased by as much as 40whp, depending on the application. But did these parts give us the most for our money?

Ultimately, we want the maximum horsepower per dollar. And after spending an afternoon with Snow Performance, they got us thinking about a more cost-efficient way to accomplish this with water-methanol injection.

Snow Performance isn’t your run-of- the-mill tuner shop. They consist of engineers specializing in mad science, fancy equations and product design. Matt Snow started the company in 2000 after a personal experience with his supercharged Mustang. He blew head gaskets left and right, so started playing with water injection to remove his detonation problems and added more than 100hp to his ’Stang. The business was established and water-meth took off from there.

Now headquartered in Colorado, Snow develops water-meth components, controllers and complete kits. Whether Euro, JDM, domestic or diesel, Snow has it covered, along with dyno tests and detailed instructions for almost every application.

What’s Meth?
Methanol is a high-octane chemical with heat properties that allow it to act like an air charge-cooler. When blended with water, the mixture is injected into the engine’s fuel and air mixture before it reaches the combustion chamber. The methanol evaporates under the high temperatures of a firing cylinder, causing heat to be pulled away from the incoming air.

This cooling process allows an engine to safely run more advanced ignition timing and boost, hence making more horsepower. It simulates an octane boosting effect on the fuel and reduces detonation. Also, meth can clean carbon deposits from the combustion chamber.

If you’ve thought about buying a BMW in the last five years, chances are you had your eye on the N54 engine in the 135i, 335i and 535i (plus X6 and Z4). These models sported the attractive 3.0-liter twin-turbo straight-six rated at 300hp and 300 lb-ft of torque. The engine packed an explosive punch with little sign of lag. The power was instantaneous and rewarding, more entertaining than comparable engines.

Eurp 1107 02+2008 bmw+135 engine Photo 2/5   |   N54 3.0L turbo motor spun the dyno to 131.43whp over stock thanks to piggyback ECU, Snow water/meth injection and nitrous shot. Meth and nitrous are activated by throttle switches, but have safety over-rides. All hardware is removable

For being BMWs first turbo engine in decades, tuners were chomping at the bit to unlock the N54’s ECU and squeeze more power from it. In fact, tuners were seeing impressive gains with both software flashes and piggyback systems.

In et 2/10, we flash-tuned our belated Project 135i with a GIAC stage 1 software. Tested on the dyno, we gained 41whp and the car was noticeably quicker. Snow Performance realized the benefits of chip-tuning and took it a step further.

The Test
To get familiar with the N54, Matt Snow picked up this clean ’08 135i as a new project car. Virtually stock except for lowering springs, the real magic is hidden. This 1er pushed 131.43whp more than its baseline dyno thanks to a software upgrade, water-meth injection and nitrous. Best of all, the conversion is safe, costs under $1500 and is reliable enough for Matt to let his wife drive it everyday without breaking a sweat.

The first order of business was a Burger Motorsports JB3 module. This Juice Box is a plug-n-play solution that works alongside the stock ECU. It overcomes the hidden “tuner detection” codes and adjusts boost, timing and other parameters to enhance performance. The module has safety nets to protect the engine from boost spikes to preserve reliability. The module can also be unplugged whenever you want and costs around $500.

Monitoring the chipped 135i on the dyno, Snow recorded a 25.8whp gain, taking it to 321.85hp from the stock 296.02whp. The results were adequate but after making several runs, they noticed some spark knock. The ECU was pulling timing because the motor was pushed passed the safety limits dictated by the factory closed-loop knock control on standard 91-octane fuel. It was time to introduce water-meth…

Using a 49% meth, 51% water mixture, which Snow sells as Boost Juice, the solution is injected through a nozzle into the charge pipe before the throttle body. The water-meth system is activated when the engine creates boost. The cooling effect from the meth allows the ECU to add more timing, which eliminates the spark knock and provides more power. Through continuous testing and monitoring, Snow’s kit ensures an optimum 12:1 air/fuel ratio.

From the previous JB3 dyno, the water/meth gained another 17.11whp to take the 135i to 338.96whp.

This improvement came from Snow’s stage 2 kit, which includes the water-meth pump installed in the trunk’s battery cavity. The appropriate plumbing is also included, which is routed alongside the fuel lines. It also comes with a three-quart reservoir that’s said to last about a tank of gas, depending on your driving habits.

For Snow’s project car, Matt chose to install a 2.5-gallon reservoir, which easily lasts a couple of track days or several weeks on the road.

Eurp 1107 03+2008 bmw 135+resevoir Photo 3/5   |   Loading up the Boost Juice

For around $400 (with an additional $50 for the larger tank), Snow had safely accomplished a significant power gain that comes cheaper than most exhaust and intake systems in the market.

Got NOS?
Now it’s time to stir some controversy. Everybody knows nitrous oxide is one of the cheapest ways to make power, but you’ve probably heard horror stories about motors blowing up as a result of using it. Yet with the combination of water-meth, Snow claims to have eliminated these pitfalls.

Tested on its 135i, a 75hp-shot dry system from Nitrous Express produced 427.55whp. That’s 131.43whp over stock!

The whole system works in conjunction with the water-meth. When the turbos begin to spool, the water-meth pump is activated, which immediately flicks open the nitrous solenoid as well. The nitrous and water-meth work as teammates, so when the nitrous breaks down in the combustion chamber, it essentially creates more oxygen. And while this would normally make an engine run leaner and hotter, the water-meth comes into play, keeping temps cool. This has the effect of boosting the octane and making the nitrous safe.

Eurp 1107 04+2008 bmw 135+drilling hole Photo 4/5   |   Tapping the charge pipe for the water-meth nozzle – installation takes about three hours

The universal Nitrous Express kit comprised all the necessary hardware including safety features that ensure the gas is only used if the RPM is perfect, the air/fuel ratio is just right, there’s enough pressure, etc.

The kit is also fairly inexpensive, costing less than $400 with a 10 lb bottle. And with the nitrous and meth, Snow discovered the N54’s factory fuel components didn’t need to be modified.

With months of testing on the dyno and at the track, Snow Performance has come up with a solution that would take an N54 engine and make it faster than a mildly-tuned M3 V8. And best of all, the stage 2 kit doesn’t require any modifications to the interior or require an expensive exhaust or intake. You’ll still look and sound like the factory 135i, but with explosive power.

Test Drive
We had the chance to drive the Snow 135i and were impressed by two things. Firstly, despite all the extra components, it’s virtually invisible both visually and to your right foot. We’d expected the engine to be slightly hesitant as the meth and nitrous were injected but that wasn’t the case. Everything operated seamlessly and smoothly.

Eurp 1107 05+2008 bmw 135+dyno Photo 5/5   |   Stock 296.02whp, software 321.85whp, water-meth 338.96whp, nitrous 427.45whp

What’s different is the catapult power delivery that allows the 135i (or any N54 engine) to pull hard once it’s making boost. And it happens from low revs.

Driving at slow speeds, the car felt docile and well behaved. But once the road opened up and we were safely able to push the pedal to the floor, the added software, meth and nitrous gave the 135i a mighty punch.

What’s nice is it didn’t alter the car’s character. It simply gave you more of what you paid for. It felt like there was a V8 under the hood and although we only had a short time with the car, it was a very positive experience.

There aren’t too many ways to get an additional 130whp this cheaply and seemingly safely. Of course, you’ll need to check on your State’s laws about carrying nitrous bottles in the trunk, but Snow Performance has produced a great bang for your buck.


Snow Performance


Snow Performance
Woodland Park, CO 80863
By Greg Emmerson
1078 Articles



Now just because a wheel is old-school and rare, doesn't mean it's sought after by enthusiast. Ugly, striking, unusual, atypical, over-priced, whatever you want to call it, here are 20 of the coolest old-school wheels ever released.
Jofel TolosaMar 20, 2020
Understanding the basics of rims and how they relate to vehicle fitment
Aaron BonkMar 16, 2020
This swap may scare some people because it requires cutting off part of the front rad support and welding on the JDM one. Don't be intimidated, though-it's not as hard as it may look.
Peter TarachMar 14, 2020
Simply put, the amount of power lost to the forces of inertia, drag, windage, pumping and friction are different for every engine, transmission and driveline design.
David PratteMar 9, 2020
Sponsored Links