Automotive WIs - BMC's Two Engine Paths

Out of the following two options which engine development path should BMC have chosen?

  • Nissan-inspired (e.g. Evolutionary Engine Design)

    Votes: 4 57.1%
  • Volkswagen-inspired (e.g. Clean Sheet Engine Design)

    Votes: 3 42.9%

  • Total voters
    7
BMC in OTL had around two engine development paths to choose from that can essentially be dubbed as the Nissan and Volkswagen routes, each with their pluses and minuses.

Out of those two engine paths, which one would BMC have been better off pursuing assuming the company had the same level of competency as Nissan and Volkswagen respectively?


1)- Nissan (aka Evolutionary Engine Design) as embodied in ideal developments to the A-Series (also A-Plus/A-OHC) and B/O/M/T-Series (plus L/G-Series diesels and Project Storm modular 4/5/6-cylinder diesels) plus their successors, by drawing inspiration from the Nissan A/E, MA, CG/CR for A-Series descendants and CA/SR engines (with the CA being an indirect descendant of the B-Series as it was an up-scaling of the Nissan E engine).

Interestingly Nissan had some pre-existing links with Austin up to the 1950s and basically developed new engines derived from improvements to the A-Series and B-Series engines, with a number of Nissan engines sharing some distant relation and other elements to the Austin units to the point where certain parts on the latter can reputedly be switched with Nissan parts with little to no issues.

Ideally come the mid-80s to early-90s in this ATL BMC scenario the A-Series (now an OHC from early-70s) would be replaced by a British built analogue of the Nissan CG/CR in 1000-1600cc forms (capable of spawning 3-cylinder, diesel and turbocharged variants), while the ATL M/T/L-Series would be replaced by an alternate petrol and diesel version of the modular Project Storm engine family in 4/5/6/8-cylinder engines.

In the case of 6-cylinder and V8 engines, it has been demonstrated that 6-cylinder versions of the 1200cc A40 / B-Series engines were developed. With the A40-derived inline-6 taking on the C-Series moniker prior to being abandoned and the B-Series forming the basis of the Blue Streak engine. While Tadek Marek before leaving Austin to move to Aston Martin developed an A40-derived V8 engine that did not reach production.


2)- Volkswagen (aka Clean Sheet Engine Design) as embodied in the 9X and E/S-Series plus their successors via the Volkswagen EA111/EA211 and EA827/EA113 engines

In the case of the E-Series in spite of preceding the Volkswagen EA827 the former has a number of similarities to the latter such as both being undersquare / long-stroke engines despite the E-Series being limited due to the bore centres being 6mm shorter compared to the EA827 as well as having siamised bores and being a tall engine (the latter of which notoriously ruined Harris Mann’s original sketch for the Austin Allegro in OTL, an issue that could have been mitigated with an end-on gearbox instead of BMC’s in-sump layout).

However despite the E-Series being originally conceived at BMC to replace the A/B-Series and C-Series engines at once, the OTL Volkswagen EA827 demonstrates why in reality a 60 hp 1.3-litre EA827 OHC let alone an E-Series of the same displacement would NOT have been a significant improvement over the existing 1.3 A-Series OHV that already produced similar power or even the 63+ hp 1275cc A-Plus and unbuilt 84 hp 1275cc A-OHC engines (the E-Series was designed to go as low as 1160-1300cc with the Volkswagen EA827 itself initially being conceived as a 1200cc engine).

3-cylinder versions of the E-Series and EA827 were also developed with the latter actually being produced in both petrol and diesel forms (with earlier versions considered for replacing the old 2-strokes at Wartburg - petrol and Trabant - diesel prior to the end of the Cold War), while the former formed the basis for the loosely related ECV3 engine. However it seems both Issigonis (designer of the E-Series) and Volkswagen felt both were inadequate for engines at the lower of end of the range, hence explaining the rationale for both the 9X and EA111 engines (the latter being a downscaled EA827) that also seem to share some similarities (with the latter giving some insight as to how a properly developed 9X engine could have evolved had it reached production).

Curiously it seems the EA827 also formed the basis for V8 and even V10 engines, the former in the Audi V8 (which spawned 90-degree V6s) and the latter derived from a pair of 5-cylinder EA827 Audi engines as an alternative to the V8 in the Porsche 928 prior to the V10 eventually finding its way to Lamborghini.


Notes:

The OTL Rover K-Series does not figure in this scenario since despite being developed at BL (which does not exist in this scenario) as a replacement for the A-Series, it was largely a design that owed much to Triumph rather than BMC. Additionally it could not be fitted into an original Mini as a 4-cylinder and BMW during development of the BMW MINI even dismissed the K-Series for not being compact enough against the Tritec engine, which notwithstanding BMW’s OTL ill-intentions towards Rover is worth mentioning in light of the fact that the Nissan CG/CR engine in the Micra K11/K12 are in fact compact enough to easily fit into the space of an original Mini (and being a fairly popular engine swap).

Am also NOT focusing on other outside engine options explored at BMC such as the Lancia V4 inspired 18-degree V4/V6 engine family (dismissed due to tooling costs as well as inability to be mounted transversely), despite Volkswagen later developing the similar VR6 engine family (spawning VR5 along with W8/W12 engines) or hypothetical A/B-Series analogues derived from the Morris-developed BMC C-Series (entailing earlier PODs).
 
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Here are a pair of parallel ATLs per decade showing both the Nissan-inspired (Evolutionary) and Volkswagen-inspired (Revolutionary) engine design routes:

-1960s-

Nissan-inspired:


A-Series – Essentially an early A-Plus with a 5-bearing crankshaft and 8-port head. Diesel version was developed with help from Ricardo Engineering as a more automotive friendly version of the OTL 948cc diesel tractor engine (a variant of which was to allegedly power commercial versions of the Mini).

721 = 28-33

848 = 33-39

998 = 39-46

1098 = 53-67

1275 = 63-78 (up to 83+)

1275 Diesel = 28

*- Had the A-Series been developed differently (via earlier PODs), its OTL 1275cc limit would have instead been around 1596cc or roughly similar to the loosely related Nissan E and A engines which feature displacements of 1487-1597cc.

**- Additionally such a development would have also potentially allowed it to follow the example of its 803-1493cc rival at Triumph by forming the basis of a small inline-6 akin to the Triumph I6 (especially since the A-Series already has a stronger bottom end compared to the 4-cylinder Triumph unit), which later laid the groundwork for the loosely related Triumph PE166.


B-Series / B-OHC / B-Series Twin-Cam – Similar to real-life aside from Twin-Cam being reliable, with BMC taking the opportunity to uprate the B-Series to 2-litre, along with adopting B-OHC and 6-cylinder (fully developed Blue Streak) / V8 versions.

1.6 = 59-90 (OHV) / 94-97 (OHC) / 100-108 (Twin-Cam)

1.8 = 82-94 up to 98 (OHV) / 105-107 (OHC)

2.0 = 106 (OHV) / 112-115 (OHC) / (Twin-Cam)

2.4 Six = 80-115 (OHV)

2.7 Six = 131 (OHV)

3.0 Six = 150 (OHV)

3.6 V8 = 164+ (OHV)

4.0 V8 = 212 (OHV)

2.0 Diesel = 55 (developed in place of 40-50 hp 1.5-1.8 B-Series diesel)


Volkswagen-inspired:


E-Series – More akin to a mid/late-60s Volkswagen EA827 with Downton tuning, featuring 88.5mm bore centres (6mm more compared to OTL and 0.5mm more compared to the OTL Volkswagen EA827's 88mm bore centres) sans siamised cylinder bores. In one of Alec Issigonis’s biographies, paper sketches reveal that diesel 1.5-1.75 E-Series were envisioned (likely as replacements for the 1.5-1.8 B-Series diesels) though ultimately did not progress beyond paper. As with the EA827-derived 3.6 Audi V8, it is likely the latter would drift away from the E-Series in order to grow beyond its current 4-litre displacement limit (see later 4.2-litre Audi V8). Curiously OTL Oettinger tuned versions of the EA827 put out 136 in 1.6 16v petrol and 90-110 hp in 1.6 diesel forms.

1.4 = 64-78 (potentially up to 84-90 hp)

1.6 = 80-103 (as low as 73 hp)

1.8 = 90-109 (as low as 82 hp)

2.0 = 110-120 (potentially up to 135 hp)

2.0 Turbo = 128-242 (potentially as much as 275+ hp)

2.0 I5 = 91-129

2.3 I5 = 113-136

2.4 I6 (or 90-degree V6) = 110-155

2.7 I6 (or 90-degree V6) = 123-164

3.0 I6 (or 90-degree V6) = 135-203

3.6 V8 = 180-218

4.0 V8 = 220-270

5.0 V10 = 275-338 (experimental – potentially capable of 370+ hp)

1.6 Diesel = 50-56 / 68-79 (Turbodiesel - potentially capable of 90-110)

2.0 Diesel = 62-70 / 85-99 (Turbodiesel)

2.5 I5 Diesel = 77-88 / 106-124 (Turbodiesel)

2.4 I6 (or 90-degree V6) Diesel = 75-84 / 102-118 (Turbodiesel)

3.0 I6 (or 90-degree V6) Diesel = 93-105 / 128-149 (Turbodiesel)



-1970s-

Nissan-inspired

A-OHC – Essentially an OHC conversion of the alternate A-Series that now features a common 70.64mm bore akin to the South African built A-Series engines as well as the A-OHC prototypes. Updated 1275 Diesel / Turbodiesel was developed by Perkins.

848 = -52

970 = -59

1097 = 72 (some debate with the displacement was 1071cc or 1097-1098cc)

1275 = 84

1275 Turbo = 106-130

1275 Diesel / Turbodiesel = 36 / 55

*- In OTL a number of upgrades to the A-Series were investigated from the 1950s and beyond, none of which entered production ranging from: alloy head, all-alloy versions, SOHC, limited-run DOHC on 1000cc / 1300cc versions, 7/8-Port Head, limited-run hemispherical heads / hemispherical combustion chambers on 997cc version, Cam-Belt / Belt Camshaft drives and 5-bearing crankshaft.

Somewhat understandably BMC or specifically Issigonis opted for the half-baked OTL E-Series to rashly solve their engine issues at once, though in retrospect the E-Series like the Volkswagen EA827 was an inadequate engine at 1300cc or below and the company would have been better off opting instead for an evolutionary approach to updating the A-Series before an all-new replacement could eventually be developed.


O-Series
– Unlike the real-life engine it is an all-new design that features no carry over from the B-Series, also includes elements of M/T-Series petrols and Perkins Prima / L-Series diesels. It is also likely the V8 versions would have drifted away from the O-Series, allowing to grow beyond its 4-litre displacement.

1.6 = 84-102 (OHC) / 107-110 (Twin-Cam)

1.8 = 95-115 (OHC) / 121-124 (Twin-Cam)

2.0 = 105-127 (OHC) / 134-138 (Twin-Cam)

2.0 Turbo = 140-160+ (OHC) / 177-275 (Twin-Cam)

2.4 Six (or 90-degree V6) = 126-153

2.7 Six (or 90-degree V6) = 142-173

3.0 Six (or 90-degree V6) = 158-191

3.6 V8 = 190-230+

4.0 V8 = 210-254+

2.0 Diesel = 62 / 81-114 (Turbodiesel)

3.0 Six (or 90-degree V6) Diesel = 93 / 122-171 (Turbodiesel)


Volkswagen-inspired:


9X – Akin to real-life (featuring scope for twin-cam versions) though an Issigonis Gearless Mini prototype featuring a 1.5 4-cylinder would suggest it was capable of spawning a 2.2 6-cylinder as opposed to a 1.3-1.5 6-cylinder, however its apparent similarity to the EA111 would transform the ATL 9X unit to displace as much as a 1.6 4-cylinder, along with a 2.0 5-cylinder and 2.4 6-cylinder. The diesel versions draws inspiration from 1.3-1.4 EA111 diesels in mk2 Volkswagen Polo.

750 = 45

875 (or 850) = 51-53

998 = 60

1300 = 77

1600 = 96

2000 I5 = 120

2400 I6 = 144

1.3 Diesel = 44

1.6 Diesel = 55



E-Series – As appeared in mid/late-60s with similar long production life as OTL Volkswagen EA827


-1980s+-

Nissan-inspired:

K-Series – appears in place of OTL K-Series, it is essentially a British analogue of the Nissan CG/CR engines with elements of the Renault K-Type diesels and an ATL version Rover’s Variable Valve Control (VVC) system. Or to put it another way, it is the A-Series equivalent of the O/M/T-Series in the sense of being an all-new design that while not carrying over anything from the A-Series / A-OHC, does feature historical nods to the previous engine by featuring similar displacements e.g. 998-1275cc, etc.

748 I3 = 41-53+

748 I3 Turbo = 70-86

956 I3 = 56-68

956 I3 Turbo = 89-110

998 = 55-70

1275 = 74-90

1275 Turbo = 119-147

1390 = 81-121

1390 Turbo = 130-160

1598 = 93-140

1598 Turbo = 149-184+

1275 Diesel = 52-88 (up to 96 hp)

1598 Diesel = 65-120

L-Series – despite carrying over name of real-life L-Series diesel engine, it can be best described as an alternate production version of the modular 4/5/6-cylinder Project Storm diesel engine that also spawned petrol and V6/V8 variants, with the petrol 4-cylinder featuring elements of the Nissan SR engine and an ATL version Rover’s Variable Valve Control (VVC) system.

1.8 = 110-138 (up to 182+ hp)

2.0 = 134-171 (up to 202 hp)

2.0 Turbo = 160-276+

2.5 I5 = 150-168

2.7 I6 (or 90-degree V6) = 165-186

3.0 I6 (or 90-degree V6) = 180-222

3.6 V8 = 220-248

4.0 V8 = 268-296

2.0 Diesel = 84-160

2.5 I5 Diesel = 105-200

2.7 I6 (or 90-degree V6) Diesel = 113-216

3.0 I6 (or 90-degree V6) Diesel = 126-240


Volkswagen-inspired:

9X 2nd generation – 3-cylinder versions derived from unused scope for 6-cylinder versions.

750 I3 = 42-47

1.0 I3 = 57-63

1.2 I3 = 68-75

1.0 = 63-73

1.3 = 80-98

1.6 = 101-123

1.0 I3 Diesel = 50-62

1.2 I3 Diesel = 60-74

1.3 Diesel = 66-83

1.6 Diesel = 80-99


S-Series – Despite carrying over the OTL S-Series name, it is essentially an updated version of the Volkswagen EA827-style E-Series.

1.8 = 123-137

2.0 = 148-153

2.0 Turbo = 165-330

2.5 I5 Turbo = 203-413

2.5 90-degree V6 = 170-190

2.7 90-degree V6 = 184-206

3.0 90-degree V6 = 222-230

3.6 V8 = 246-274

4.0 V8 = 296-306

5.0 V10 = 370-383

1.6 Diesel = 75-133

1.8 Diesel = 84-150

2.0 Diesel = 93-165

2.3 I5 Diesel = 104-185

2.5 I5 Diesel = 116-206

2.5 90-degree V6 Diesel = 139-170

2.7 90-degree V6 Diesel = 150-184

3.0 90-degree V6 Diesel = 165-203

4.0 V8 Diesel = 221-264 (up to 271+hp)

5.0 V10 Diesel = 276-339
 
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BMC in OTL had around two engine development paths to choose from that can essentially be dubbed as the Nissan and Volkswagen routes, each with their pluses and minuses. Out of those two engine paths, which one would BMC have been better off pursuing assuming the company had the same level of competency as Nissan and Volkswagen respectively?
I'd have to spend some more time puzzling out the technical details–engines not being my forte–but my initial reaction would be to go with the Nissan route.


Interestingly Nissan had some pre-existing links with Austin up to the 1950s and basically developed new engines derived from improvements to the A-Series and B-Series engines, with a number of Nissan engines sharing some distant relation and other elements to the Austin units to the point where certain parts on the latter can reputedly be switched with Nissan parts with little to no issues.
Aside from the engine licenses you mentioned it goes back even further with Nissan producing Austin Sevens in their early days – some on-line saying under license, others as clones but modified just enough to avoid legal problems. You wouldn't happen to know which it was do you?

Talking of 'homages' there's the Wolseley Eight engine – an OHV one developed from the Morris side-valve, which was in turn a knock-off of Ford's engine from the Model Y. IIRC Ford also developed theirs into an OHV engine that found its way into the post-war Taunus models. Would there be space for it anywhere, or would BMC concentrate on the Series engines to take advantage of the streamlined product range do you think?
 
One issue with the Nissan route, would be fitting the 1.6 B-OHC engine into the ATL 1100/1600 (see Morris Nomad) or ATL Maxi in place of the OTL E-Series engine (beyond a few prototypes). However an A-Series that developed differently compared to OTL with the ability to be enlarged from 1275cc to 1596cc would have greatly helped matters. If it would end up proving to be a challenge to fit a 6-cylinder B-Series into the 1800 (even with a front-mounted as opposed to the initially planned side-mount radiator for the E-Series which crippled the latter), then the fact this ATL A-Series was capable of growing to 1596cc would have opened up the possibility of developing a small more compact 2.0-2.4-litre+ inline-6 like their rivals at Triumph.

At the same time it is worth mentioning both the Maestro and Montego were 1970s designs (under the ADO99 name) that were originally intended to be fitted with A-Series and 1.7-2.0 O-Series engines, via the ATL Nissan route both cars would have featured ATL 1.6-2.0 O-Series and without the mess of OTL BL (or distraction of other projects) would have potentially been launched much earlier.

Aside from the engine licenses you mentioned it goes back even further with Nissan producing Austin Sevens in their early days – some on-line saying under license, others as clones but modified just enough to avoid legal problems. You wouldn't happen to know which it was do you?


Speaking of the Seven. There is still debate as to whether the Seven copy made by Datsun / Nissan was licensed or not, however it seems Austin decided they were sufficiently different as to not pursue legal action. - https://en.wikipedia.org/wiki/Datsun_Type_11#Relationship_to_Austin_Seven

To go off on a slight tangent, it would have been interesting seeing Austin further develop the prewar Seven like BMW (via 3/20), American Austin / Bantam and Datsun did in OTL. To the point of bringing an early/mid-1930s Austin Big Seven / Datsun DS type car with a 20-28 hp 747-860cc OHV engine to the market, prior to being replaced by an earlier Austin 8-derived 7 replacement with a 25-27 hp 747cc OHV version of the ATL 30-33 hp 900cc Austin 8 OHV engine.

Talking of 'homages' there's the Wolseley Eight engine – an OHV one developed from the Morris side-valve, which was in turn a knock-off of Ford's engine from the Model Y. IIRC Ford also developed theirs into an OHV engine that found its way into the post-war Taunus models. Would there be space for it anywhere, or would BMC concentrate on the Series engines to take advantage of the streamlined product range do you think?

As for the Morris Eight / Wolseley Eight engine, it is possible for the engine to grow beyond its planned OTL pre-BMC 960-980cc OHV displacement to as much as 1600cc with the right PODs (Miles Thomas replaces Lord Nuffield and realises investment / modernization plans with Nuffield pushed into a scheming figurehead role), worth mentioning Ford managed to push the engine to as much as 1758cc.

Also though the Wolseley unit pushed out 33 hp, an Alta OHV conversion of the 918cc Morris SV pushed power to as much as 38-49 hp (and that is not even mentioning if Harry Weslake gets involved in ATL like he did with unrealised OTL plans for a redesigned Morris developed C-Series engine).

Additionally the OTL Morris developed "C-Series" 6-cylinder OHV was derived from an earlier post-war 4/6-cylinder engine family (in both SV and primitive OHC forms), with a 1100cc OHC planned for an MG version of the Morris Minor, while a 2-litre 4-cylinder C-Series was later developed during the MGB project.

To answer your question as to whether there would be room for both Morris developed engines within this ATL BMC range, it would depend on whether Lord Nuffield is deposed in the postwar period along with his outdated and parsimonious thinking (he believed Morris's should remain SVs and sabotaged the Minor).

With Nuffield deposed, allowing the Wolseley OHV to power the Minor (and grow to as much as 1600cc) with the Morris 4/6-cylinder (an ATL earlier thoroughly-developed C-Series lightened by 175 lbs / 80 kg) being OHV from the outset (prior to being converted to OHC and later reliable Twin-Cam as envisioned by Gerald Palmer - with elements of the Mercedes-Benz derived Nissan L engine). Both would have provided a stiff challenge to the A-Series and ATL B/C-Series (aka 4/6-cylinder B-Series).

While the Wolseley OHV being a prewar design (derived from the Ford Sidevalve) would count against it in favor the A-Series, the ATL 918-1600cc Wolseley OHV could have probably remained in production as late as the early/mid-1960s (like the Ford Taunus P3) or beyond in certain non-European markets.

Whereas the Morris 4/6-cylinder aka OTL C-Series (putting out as much as 150-190+ hp) could have lasted longer as well since Morris himself dreamed of the Morris Six MS / Isis and the 6-cylinder engine challenging the original Holden 48-215 and subsequent Holden models.

So in this ATL Nissan route, the A-Series and B/C-Series (4/6-cylinder B-Series) would dominate in UK/Western markets while the Wolseley OHV and Morris 4/6-cylinder would survive for a bit longer outside of European/Western markets.
 
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I'd have to spend some more time puzzling out the technical details–engines not being my forte–but my initial reaction would be to go with the Nissan route.

The OTL E-Series was limited by a number of factors which would not exist in ATL Volkswagen route scenario. Also both Volkswagen and Nissan routes would have entailed ATL BMC eventually adopting a end-on gearbox layout from the late-60s to early-70s onwards, which would have solved the E-Series issue of being a tall block mated to an in-sump gearbox layout.

However if BMC is solvent in this scenario and able to bring ideas to market much quicker, it it possible the lower-end models would continue to use the in-sump layout for a bit longer on FWD models. Eventually topped by a 5-speed manual in-sump gearbox (an earlier version developed by Jack Knight for the Mini though also including 1100/1300 and Allegro type models) along with a 5-speed AP Automatic gearbox developed by Keith Gerrard of Bushey Transmission (in conjunction with Jack Knight) until the late-70s to early/mid-80s (which was fitted with a clutch with extra radial shock springs in place of a torque converter and an electronic shift mechanism).
 
In some respects it is a shame that despite being the 4th largest carmaker upon its formation, BMC unlike other carmakers such as the Big 3 or elsewhere were never in a position to utilize both Nissan or Volkswagen inspired engine routes.

Was previously of the view that the OTL E-Series had little scope for being developed into a better engine with the right circumstances, in spite of being conceived to replace the OTL A-Series, B-Series and C-Series engines at once, the main sticking point being the fact its siamised bores precluded it from being enlarged to a 2-litre 4-cylinder to adequately serve as a viable alternative to the 2-litre O-Series plus successors (let alone a 2-litre B-Series) even as a hypothetical 2-litre 5-cylinder.

It was only upon finding out its similarity to the later Volkswagen EA827 which ultimately changed my perspective, and thus making it difficult to answer whether BMC should have adopted the Nissan route and saved money or opted instead for the Volkswagen route. Both would have entailed the company having a pair of reliable scalable engines with quite a bit of longevity, based on what Nissan and Volkswagen manged to achieve with their range of engines in OTL.
 
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