BMW E34 535i Spiked

The ARC2 works along with your existing engine management computer to extract peak performance from your engine.

E34535i4  E34535i3

E34 535i


E34535i  E34535i2

Installation of the Split Second ARM1 and ARC2


E34535i5  E34535i6  e34535i8  e34535i7

Installation of the E34 535i MAF kit



Dyno Data Referred to Rear Wheels


click here for MAF kit information

We have dyno tested the conversion on an E34 535i. The result in doing a direct comparison of the MAF vs. AFM meters was an increase of 16 hp and 13 ft-lbs. of torque accross the board referred to the flywheel.

Performance Referred to Flywheel:
(.8 correction factor used)

Maximum Horsepower Gain 16 hp
Maximum Torque Gain 13 ft-lb
Peak Horsepower 228 hp
Peak Torque 244 ft-lb


Horsepower Torque
RPM Air Flow Meter Mass Air Flow Sensor Improvement RPM Air Flow Meter Mass Air Flow Sensor Improvement
3000 140 141 1 3000 250 250 0
3500 154 163 9 3500 238 241 3
4000 198 208 10 4000 259 273 14
4500 244 250 6 4500 281 291 10
5000 263 281 18 5000 278 296 18
5500 290 301 11 5500 285 288 3
6000 301 315 14 6000 265 275 10
6500 294 306 12 6500 238 250 12

Comparison is between a modified E34 535i and one modified with the Split Second E34 535i MAF Kit

The conversion is accomplished with a MAF3.5 sensor, the Split Second ARC2 Air/fuel Ratio Calibrator and the ARM1 Air/fuel Ratio Meter.

The MAF sensor gets rid of a major restriction on the intake of the engine resulting in significantly more power accross the board. Unlike TPS or MAP sensors, use of the MAF sensor provides a flow type signal similar to the vane style air flow meter.

The ARC2 does all the signal conditioning necessary to convert the output of the MAF sensor to look like an air flow meter signal to the ECU. Therefore the ECU continues to operate in exactly the same manner, with the same fuel and ignition mapping. This results in more horsepower with no degradation in driveability. In fact the driveability is improved due to the improved throttle response. The ARC2 does important signal filtering and conditioning so the conversion works well over temperature and elevation changes.

Since the conversion to the MAF sensor does not involve a change to the PROM in the ECU, you can use whatever chip you like and change anytime you want to alter the ignition and fuel mapping. You are not locked into a particular chip.

The controls on the ARC2 give you the ability to range your engine back into proper operation if you make any other modifications in the future. Say you modify the air filter which alters the flow across the MAF sensor element. Or, you might go to bigger injectors, a higher fuel pressure regulator or bigger exhaust. The ARC2 provides a way to immediately dial-in operation for peak performance.

The MAF conversion can be changed back to air flow meter operation anytime by reinstalling and plugging in the air flow meter. This makes it easy to do a comparison.

The ARC2 calibrator works in any vane meter application. This means that you can take it off one car and use it on a different model. It will work equally well on an M3, M5, Porsche 911, Toyota MR2 or any other car with an air flow meter based fuel injection system.

The ARC2 has 4 knobs which are set by monitoring the ARM1 air/fuel ratio meter. The low control is set at idle so that the meter dithers indicating the fuel mixture is within the closed loop control range of the ECU. The high control is set for dithering under moderate loads. The fuel curve is then optimized by adjusting the mid control and going back to fine tune the low and high. The accel control is adjusted for proper engine response off of idle.

Use of the ARC2/ARM1 combination gives the user a greater appreciation for how the engine is operating as well as a means to monitor and adjust air/fuel ratio whenever engine modifications are made.