BMW M70#S70/1

The M70's design is similar to that of two 2.5 L M20 straight-six engines joined at a 60-degree angle,{{cite web|title=The 8-Series Was One Of BMW's Best Failed Experiments|url=http://jalopnik.com/the-8-series-was-one-of-bmws-best-failed-experiments-1585763392|website=www.jalopnik.com|date=5 June 2014 |access-date=30 July 2017}} due to the following features: single overhead camshaft valvetrain, bore spacing of {{convert|91|mm|in|1|abbr=on}}, bore of {{convert|84|mm|in|2|abbr=on}}, stroke of {{convert|75|mm|in|2|abbr=on}}, and a compression ratio of 8.8:1.{{cite web|title=1989 BMW 750i E32 Specification|url=http://www.carfolio.com/specifications/models/car/?car=14322|website=www.carfolio.com|access-date=4 August 2017}}

The M70 has the following differences with the M20 engine:

• Aluminium alloy engine block (AluSil) instead of cast-iron (both engines have an aluminium cylinder head), to reduce weight.{{cite web|title=BMW M70, M72 and M73 V12 Engines|url=http://www.unixnerd.demon.co.uk/m70.html|website=www.unixnerd.demon.co.uk|access-date=4 August 2017|archive-date=7 January 2016|archive-url=https://web.archive.org/web/20160107232007/http://www.unixnerd.demon.co.uk/m70.html|url-status=dead}}
• Airflow measurement using Mass air flow sensors (MAFs){{cite web|title=7' E32 750iL Mass air flow sensor|url=http://www.realoem.com/bmw/en/showparts?id=GC81-EUR-02-1987-E32-BMW-750iL&diagId=13_1379|website=www.realoem.com|access-date=30 July 2017}} instead of Air flow meters (AFMs) to improve fuel economy.
• Electronic Throttle Control instead of a mechanical throttle cable.
• A timing chain was used instead of a timing belt,{{cite web|title=7' E32 750iL Timing and valve train-timing chain|url=http://www.realoem.com/bmw/en/showparts?id=GC81-EUR-02-1987-E32-BMW-750iL&diagId=11_1190|website=www.realoem.com|access-date=30 July 2017}} to reduce servicing requirements.
• Hydraulic valve lifters instead of mechanically adjusted tappets, to reduce servicing requirements.

The M70 has two Motronic 1.3{{cite web|url=https://kfzdiag.de/mediafiles/Verwendungslisten/BMW.pdf|title=BMW|access-date=1 February 2019|archive-date=2 February 2019|archive-url=https://web.archive.org/web/20190202212921/https://kfzdiag.de/mediafiles/Verwendungslisten/BMW.pdf|url-status=dead}} ECUs (one for each cylinder bank). To provide redundancy, the M70 also has two fuel pumps, fuel rails, distributors, mass air flow sensors, crankshaft position sensors, coolant temperature sensors and throttle bodies.{{cite web|title=V12 (M70) Regular Maintenance|url=http://bmwe32.masscom.net/sean750/v12_cross_referencing/v12regularMaintanance.htm|website=www.bmwe32.masscom.net|access-date=4 August 2017}}

Some M70 engines (such as fitted to the E32 750iL Highline) are fitted with two alternators. The second alternator is smaller and is used to charge an auxiliary battery and power equipment in the rear passenger compartment, such as a telephone, fax machine, wine cooler, independent climate control and power sun shields.{{cite web|title=Engines Exposed: Just How Far Has BMW's Beastly V12 Come?|url=http://www.carbuzz.com/news/2016/2/5/Engines-Exposed-Just-How-Far-Has-BMW-s-Beastly-V12-Come-7731822/|website=www.carbuzz.com|date=5 February 2016|access-date=30 July 2017}}

{{notelist}}

Applications:

• 1987–1994 E32 750i/750iL – this was mated primarily to an automatic ZF 4HP24 transmission
• 1989–1994 E31 850i/850Ci – this was mated to either the automatic ZF 4HP24 transmission or the optional Getrag 560G
• 1988 Alpina B12
• 1991 BMW Nazca M12
• 1992 BMW Nazca C2

{{Infobox automobile engine

| name = BMW S70 engine

| image = 1996 McLaren F1 engine.jpg

| caption = Engine bay of a McLaren F1

| production = 1992–2000

| configuration = 60° V12

| block = Aluminium

| head = Aluminium

| displacement = {{convert|5576|cc|L|1|order=flip|abbr=on}}
{{convert|6064|cc|L|1|order=flip|abbr=on}}
{{convert|5990|cc|L|1|order=flip|abbr=on}}

| bore = {{convert|86|mm|2|abbr=on}}

| stroke = {{convert|80|mm|2|abbr=on}}
{{convert|87|mm|2|abbr=on}}
{{convert|85.9|mm|2|abbr=on}}

| valvetrain = DOHC, with VVT

| compression = 11:1

| fueltype = Petrol

| coolingsystem = Water-cooled

| power = {{convert|280-671|kW|0|abbr=on}}*(*900 PS produced only McLaren F1 GTR Long Tail specifically in full race trim upon qualification without racing restrictors){{cite web|url=https://www.motorauthority.com/news/1110784_mclaren-f1-gtr-longtail-stretches-its-legs-at-spa-francorchamps|title = McLaren F1 GTR Longtail stretches its legs at Spa-Francorchamps}}{{cite web|url=https://www.supercars.net/blog/1997-mclaren-f1-gtr-long-tail/|title = 1997 McLaren F1 GTR Long Tail | McLaren|date = 18 April 2016}}[https://www.motor1.com/news/16037/rare-race-spec-mclaren-f1-gtr-long-tail-found-on-sale/ ]{{dead link|date=August 2022}}{{cite web |url=https://www.carscoops.com/2020/06/street-legal-mclaren-f1-gtr-longtail-has-rich-history-15-million-asking-price/ |title=Street-Legal McLaren F1 GTR Longtail Has Rich History, $15 Million Asking Price |publisher=Carscoops |date=2020-06-18 |accessdate=2022-08-12}}

| torque = {{convert|550-900|N.m|lb.ft|0|abbr=on}}

| weight = {{convert|265|kg|lb|0|abbr=on}}

| predecessor = None

| successor = None

}}

The first engine to use the S70 name is a {{convert|5576|cc|cuin|1|abbr=on}} variant of the M70 engine fitted only to the E31 850CSi.{{cite web|title=Engine specifications for Motorsport engines|url=http://www.bmwheaven.com/database/engine.php?type=Motorsport#/167|website=www.bmwheaven.com|access-date=4 August 2017}} With 1,510 units produced, this is the lowest production BMW engine to date.{{cite web|title=Worldwide Shipments: S70 850CSi 1992–1996|url=http://www.8coupe.com/Production/WorldwideShipments/S70850CSi19921996.aspx|website=www.8coupe.com|access-date=4 August 2017}}

Three prototype dual overhead camshaft S70 engines were constructed, prior to the decision to not produce an E31 M8 model.{{cite web|title=BMW S70 and S70/2 V12 Engines|url=http://www.unixnerd.demon.co.uk/s70.html|website=www.unixnerd.demon.co.uk|access-date=4 August 2017|archive-date=19 August 2017|archive-url=https://web.archive.org/web/20170819052831/http://www.unixnerd.demon.co.uk/s70.html|url-status=dead}}

Applications:

• 1992–1996 E31 850CSi
• 1993 BMW Nazca C2 Spider
• 2011 Simbol Design Lavazza GTX-R (twin-turbo version)

The S70/2, while sharing the same 12 cylinder layout, bore spacing and design principle as the S70B56, is essentially a new design with the heads based on the European market S50B30,{{cite web|title=BMW Classic – Recherche-Client|url=https://bmw-grouparchiv.de/research/detail/index.xhtml?id=3943376|website=bmw-grouparchiv.de|access-date=28 February 2018}} and thus featuring 4 valves per cylinder and variable valve timing (called VANOS by BMW) and individual throttle bodies. A dry sump oiling system is used.{{cite web|title=1994 McLaren F1: First Drive Flashback|url=http://www.roadandtrack.com/new-cars/first-drives/reviews/a5339/performance-tests-first-drives-flashback-1994-mclaren-f1/|website=Road & Track|date=14 December 2014|access-date=4 May 2017}} The weight of the S70/2, plus ancillaries and full exhaust, is {{convert|265|kg|lb|0|abbr=on}}.{{cite web|title=F1 – McLaren's Road Car An Autocar & Motor Book|url=http://www.audiosignal.co.uk/McLarenF1.html|website=www.audiosignal.co.uk|access-date=4 August 2017}}

Applications:

• 1993–1998 McLaren F1

The S70/3 is a racing engine based on the S70/2.

Applications

• 1998–1999 BMW V12 LM racing car
• 1999–2000 BMW V12 LMR racing car
• 2000 BMW X5 LM concept car{{cite web|url=https://www.motor1.com/news/501344/bmw-x5-le-mans-video/|title = BMW Shows the X5 le Mans Concept and Its V12 Engine with 700+ HP}}{{cite web|url=https://www.caranddriver.com/reviews/a15139465/bmw-x5-on-the-ring-car-news/|title=2001 BMW X5 le Mans Concept Had the V-12 Heart of a McLaren F1|date=16 June 2020}}{{cite web|url=https://www.bmw-m.com/en/topics/magazine-article-pool/the-bmw-x5-le-mans.html|title = The BMW X5 le Mans}}

• BMW Goldfish V16

{{reflist|30em}}

{{commons category|BMW M70 engine}}

{{BMW automotive petrol engines: 1960s to 1980s}}

M70

Category:V12 engines

Category:Gasoline engines by model