It’s got that same beefy N54 twin turbo 6 as in the 335i/is and 135i/is, and like the N54 in those cars, it can make a TON of power with the right mods. If you think about it, the 535i is one of the better “sleeper” cars on the road – there’s a ton of em out there, and they have a TON of potential! And with none of the raised eyebrows you’d get in a modded out 335i or 135i. Ah, the advantages of being a sleeper.
For a while, many of the guys with the bigger E60 5-series felt like modding their N54 was an E9X’s game, and for a while- yeah, that was kinda true. But thanks to the proliferation of parts available on the aftermarket – and the fact that some of the goodies for the E9X cross over to the E60, you can beef up your straight six turbo into a monster easily within reach of eating an E60 M5’s lunch, and without that S85 pricetag either. Yeah, the 5er is a big boy- but with a beefy N54 under the hood, it can be a real heavyweight fighter – and you can look the part and go aggressive with your exterior, or just leave things alone for maximum stealth factor.
Check it out – the 6 best mods for the E60 BMW 535i.
When it comes to getting more power out of the car, you have a few options.
First and foremost, we need to address a few shortcomings of the car.
Let’s start with the single item that will yield the greatest bang for the buck with your E60 535i –
#1 A tune.
Our favorite of the devices out there currently for tuning an N54 powered 535i – is the Cobb Tuning AccessPORT – it installs a true remap tune instead of piggybacking on the stock ECU programming, and is the easiest to install. Not to mention, it’s one of the few systems LEGAL for use in California, so that’s why it’s our top pick – if you’re a Cali resident a JB4 isn’t even an option for you anymore – but that’s not necessarily even an issue, as the AccessPORT is nothing to turn your nose up at. Gains depend on the map you use and your mods, but a stock car can expect appx +80whp/+120wtq gain on pump gas (Stage I Aggressive = +30%hp +38%tq) – and MUCH, MUCH more than that with supporting mods and a custom tune by a pro tuner.
In the same vein as the ACCESSPORT but with a much more primitive flasher tool is ESS Tuning’s Flash tuner for BMW N54, but that’s a much cruder device and the gains are more conservative at around 50whp/80wtq on an otherwise stock car.
But say you live elsewhere in the USA – you have some options. As we mentioned earlier, in that case, you can go with an AccessPORT, but some of your other options are the classic standby for any N54 engine – the BMS JB4 for BMW N54 (incl E60). Programmed with seven preset “Maps”, the JB4 features a shift on the fly stock bypass map, Valet Rev-Limiter and Race Gas map as well – and this piggy-back style tuner, until recently, was the king of the hill in terms of absolute power gains until some new tuners hit the scene working with AccessPORTs – either way the JB4 is still a hell of a potent thing and will yield a whalloping 60-80whp/100-120wtq gain.
Lastly, one of the older systems on the market is the Active Autowerke Processor for E60 535i, which operates like the JB4 but yields a moderate but appreciable gain of +55whp / +70wtq on an otherwise stock car.
#2 A Blow Off Valve & Chargepipe
One of the other small items you wouldn’t think about that’s costing you power are the stock diverter valves – which are replaced by either a blow off valve or recirc valve. The reason why is because the OEM plastic valves aren’t the best seal and so they leak boost, causing slower turbo response and greater “lag”. Replacing the stock diverter valve with a BOV upgrade on your E60 535i will yield a whopping 26ft/lb improvement in the car’s power in lower gears like 1st-3rd. The other issue is that your E60 is getting old, there, buddy. As such, plastics and rubber age and don’t seal like they used to – meaning things under pressure like the plastic chargepipe itself can fail. Upgrading your chargepipe and diverter valves/BOV not only enhances performance, but it’s good preventive maintenance too as it eliminates one more potential source of failure.
You have a few options – like the Turbosmart Kompact Plumb Back Diverter Valve or Kompact Dual Port Blow-Off Valve, but other options don’t bolt on to the stock chargepipe or the direct replacement style chargepipes like COBB and VRSF.
But that’s half the upgrade here- since it’s all part of one larger thing, we’re considering a BOV and Charge Pipe all a single “mod” here.
In some cases, the BOV and the chargepipe are ordered as a unit, like Evolution Racewerks Chargepipe/Diverter Valve for N54, the Active AutoWerke Chargepipe w/BOV for N54 or TiTek N54 Chargepipe with HKS SSQV BOV – whereas with the COBB N54 Chargepipe or VRSF N54 Chargepipe, the BOV is sold separately.
#3 A Bigass Front Mount Intercooler.
We’ve said it before – a cool running engine is a happy engine. As we mentioned in an earlier post, the N54 engine runs hot from the factory and benefits from reductions in temperature – an Oil Cooler is a necessity – and an Intercooler will further help reduce engine temperatures. When looking to upgrade the power potential of your turbocharged or supercharged vehicle, one of the items that’s included in your “Stage II” and “Stage III” packages is a larger Intercooler. An intercooler is ideally that “next step” that helps support your other modifications. The OEM Intercooler for the N54 engine is a little small – it measures just 510mm x 130mm x 110mm for just 7,293 cm3 of volume. This means intake air temperatures are much higher than they need to be – and with hotter intake temperatures, the air is less oxygen-dense, meaning it doesn’t generate as much power and can lead to detonation. An aftermarket intercooler can offer as much as a 90% increase in airflow, reducing turbo lag, increasing throttle response and spool-up. The Intercooler’s piping can be as much of a restriction as the intercooler’s lack of volume, so seriously consider an intercooler upgrade that includes larger inlet/outlet piping for the greatest benefit from your intercooler. What’s more, nearly all aftermarket intercoolers eliminate the nasty and failure-prone plastic end tanks popular as OEM units.
With a bigger FMIC, yes, you WILL make more horsepower, and simply by virtue of it having a better design, the engine make more power than the OEM intercooler – but really, that’s missing the point.
(For Comparison, an OEM BMW M235i intercooler and an ER FMIC – the 535i’s is similarly undersized and goes to show you they’re still giving you a TEENY FMIC)
A bigger, high performance intercooler isn’t about making maximum power all the time – a performance intercooler is about one thing: CONSISTENCY. Yes, consistency. That sounds crazy, we know. But think about what the job of the intercooler is. Cool the air charge. It works like your radiator does, only it’s cooling down the air going into the motor instead of coolant. The air flows through the intercooler and so a cooler air charge is what reaches the throttle body. Your N54, when tuned, makes a lot more HEAT than the stock configuration. And your undersized stock FMIC can only get rid of so much heat. So, a bigger FMIC that can get rid of more heat can actually keep your tuned N54 cool by exchanging heat as quickly as your N54 is making it – and your 5er will also run much happier on extremely hot days.
Evolution Racewerks offers a great direct-fit E60 BMW 535i Front Mount Intercooler, which will keep your air charge cooler and allow you to run more aggressive tuning and therefore make much more horsepower and torque.
If you want to know more about intercoolers and how they work, check out our tech piece here.
#4 – A Downpipe & Exhaust
We’re going to wrap this into one here- but let it be said the important thing is the DOWNPIPES are what are the big horsepower/torque gain as a part of this combination. The catback and axleback exhaust for 535i is good for SOME power, but that’s mostly for sound. But if you get both, you’ll have an incredible sound and a major increase in power.
Unfortunately, AR Design, the only supplier of Catted Downpipes for the E60 535i, has gone out of business and so the downpipes are no longer available, and their part was the only direct fit option as there aren’t any other downpipes that confirm E60 fitment at this time.
#5 AN INTAKE
There aren’t many good intake systems currently on the market for the E60 535i better than the Injen Dual Cone Air Intake for E60 BMW 535i, which is good for 14whp/13wtq and significantly enhances throttle response and reduces turbo lag – and as part of the combination we’ve laid out above, it’s pretty damn effective, and the dual cone design lets you hear all that sweet sweet turbo spool action.
Injen E60 535i Intake Dyno
Scope out the dyno sheet and see for yourself.
Some say save the best for last.
#6 METHANOL INJECTION
We talked about Methanol Injection before here
Though not very popular these days, one of the most effective and simple mods you can do to your N54 is to install a methanol injection system. Having the ability to cool the intake charge effectively increases your engine’s output by cooling the outgoing pressure from your turbo. This effectively makes the air charge much cooler and more dense, and therefore more oxygen-rich. The more O2 your engine takes in, the more power it can make.
And that covers all 6 of the best mods for the E60 BMW 535i.
Thanks for joining us, and we’ll see you next time!
Story & Photos Nick Gregson