BMW S63 V8 Turbocharged M-Tech Engines

BMW S63 engine

S63TU in an F10 M5.

Chronology

The S63 was a 4.4 litre twin turbo development of the N63 V8. It was initially used to power the 2010 E70 X5M and E71 X6M models.

In 2011 A technical update version was released in co-ordination with the launch of the F10 M5, this was later used on the F12 M6 as well. The S63 replaced the 5.0 V10 S85 in these roles so had a substantial reputation to live up to.

In 2015 a second technical update was implemented, this time for the newly released F85 X5M and the F86 X6M.

BMW S63 engine

S63, note the smaller intercoolers.

Design

The design took on much of the N63's heritage. A fundamental change was the use of twin scroll turbos with a pulse tuned exhaust manifold. Twin scroll turbos have two exhaust gas inlet chambers directed at different parts of the turbine, this makes them spin up faster. Maximum boost was increased by 50% to around 17psi.

As befits a performance turbo engine compression was lowered to 9.3:1 using a new piston design. The cylinder head was redesigned to handle the addition thermal loads. Camshaft timing and lift were also adjusted.

In further attempts to manage heat the intercoolers were enlarged, an extra coolant pump was added, the transmission oil cooler was made more efficient and an additional heat exchanger was installed in the cooling system.

For the new M5 and M6 a technical update was preformed, primary goals were improved throttle response, lower turbo lag and better fuel economy. More power would be a by-product rather than a major goal. To this end the S63TU was the first engine to get third generation Valvetronic.

In addition the crankshaft, pistons and conrods were all modified, the compression ration was now 10:1. Boost was upped from 17psi to 22psi. As a result of the modified internals the rev limit could be safely raised from 6800 to 7200rpm.

BMW S63 engine

S63TU with larger square section intercoolers.

Variants

Code Size Power
bhp@rpm
Torque
lb/ft@rpm
BHP/
litre
Torque/
litre
Made Bore x
Stroke
Timing Weight
(kg)
VANOS
S63
S63TU
S63TU2
4.4 547 @ 6000
553 @ 6000-7000
567 @ 6000-6500
500 @ 1500-5650
500 @ 1500-5750
550 @ 2200-5000
124
126
129
114
114
125
2009-10
2011-14
2015 on
89x88.3 Chain ? Dual

 

BMW S63 engine

S63TU in an F10 M5.

Problems

In 2014 the N63 had a major recall for a whole host of problems, it was one of the most all encompassing in recent years. The S63 powered cars were not included in the recall, from this we may speculate that some of the N63's problems were less prevalent or had been eliminated on the S63. Indeed S63 owners are finding their M-Tech engines to be more durable than the N63. Seems like a good excuse to buy an //M car!

Due to heat issues this engines kills batteries, especially in hot climates. BMW tried high tech Absorbent Glass Mat (AGM) batteries but the problem didn't go away. There was a technical service bulletin (TSB) to replace them every oil change in some countries.