Hello from the UK

[Lotus Rebel]

Hello all, here is my admittingly very belated introduction.

 

My interest in Lotus is mainly regarding little known historical aspects of the company, along with queries on Lotus’s many projects over the decades to clarify small tidbits already partly available either online or in books (always open to any comprehensive recommendations) as well as demystifying any outlandish nonsense that has crept in over time. Also have an general fascination of exploring automotive what-ifs / alternative history (albeit premised as much as possible on what was originally considered), whether speculative or backed-up with evidence to form a more coherent picture of Lotus’s drifting product plans in the case of the latter such as:

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• -          The BMC A-Series initially being considered as the basis of a possible replacement for the Elite’s Coventry Climax engines for what became the Elan prior to the development of the Kent-based Lotus Twin-Cam before being rejected on the basis of there being no long term evolution plan for the engine. Only for Lotus to later play a role years later in the development of the MG Metro Turbo and managing to extract 120-130 hp from the engine (which was soon detuned in order to prolong the life of the gearbox due to the limitations of the latter's in-sump layout). - http://www.lotuscortinainfo.com/?page_id=3551
• -          The roots of what became the Clan Crusader being a possible replacement for either the Seven or Europa as well as allegedly being derived from the Lotus M2 prototype, though it is not clarified whether the latter was derived from the original Elan test mule (albeit converted to rear-engined RWD) or was basically another project that reused the original Elan project’s codename. The following link is one of a few passing online references available that mention the M2 project together with the Clan Crusader. - https://www.imps4ever.info/specials/clan.html
• -          Whether there was further scope in the design of the 4011cc Lotus Type 909 V8 or 1973-2174cc Slant-Four engines for even larger displacements had things gone to plan akin to the Vauxhall Slant-Four (e.g. 2279cc+), let alone investigation on a related 90-degree V6. The conceptually similar Slant-Four / V8 engine jointly-developed by Saab and Triumph (together with Ricardo) for example was designed with displacement ranges of 1250-2000cc in Slant-Four and 2500-4000cc in V8 forms, with the related Saab H Slant-Four engine being further enlarged to 2290cc.  
• -          The Norton rotary powered MG Metro prototype’s apparent links to Lotus’s Project Nora, despite it not being clarified whether this FWD 2+2 coupe was to be based on the Metro or a clean-sheet design prior to it being abandoned. - https://www.nortonownersclub.org/history/rotary
• -          The Lotus M90 / X100 also being planned to feature the 2.2 Lotus engine above the 1.6 Toyota 4AGE at one point during its development, together with the prospect of a turbocharged Toyota 4AGE preceding the 1.6 Isuzu 4XE1WT in the Elan M100.
• -          Apart from the 1.6 Isuzu X engines used in the Elan M100, was there any Lotus involvement with the all-alloy 32-valve 240+ hp 3.5-litre/3.6-litre Isuzu V8 engine used in the Chevrolet Feretta V8 prototype as a prospective V8 engine for the Esprit? Was it derived from the 350 hp 4.2-litre V8 used in the Isuzu 4200R that Lotus also had a role in developing or was it somehow based on either the Type 909 V8 or less likely the GM LT5? Also heard the Isuzu X 4-cylinder, Isuzu V V6 and the above-mentioned Isuzu V8s were related to each other along with the V12 used in the Lotus 102C F1 car and Isuzu Como concept.
• -          What was the story behind the V6 engine project Toyota gave Lotus during the 1980s, was it originally considered for the Excel, Esprit or another car by Toyota as well as if the V6 was a stillborn project or ultimately entered production as the Toyota VZ or Toyota MZ.
• -          Lotus’s work with Chrysler on a number of projects, whether the plan was for Lotus itself to use the Chrysler 2.2/2.5-litre engines in the Esprit (or Excel) in place of the 2.0/2.2 Lotus engines or for Chrysler to use the Esprit as the basis for its own halo car using said engines (along with a 255 hp 3.5-litre Lamborghini Jalpa V8 via the AWD Dodge Daytona Decepzione prototype that Lotus was also involved with).  - https://www.aronline.co.uk/opinion/chrysler-esprit/
• -          The Lotus Type 918 V8 reputedly being a clean-sheet design unrelated to the earlier 900 Series engines that was originally intended for the stillborn M220 project (despite being evolutionary as opposed to revolutionary in concept), yet based on a modular design ultimately capable of spawning inline-four, V-4, and/or V-6 offspring. How much growth in displacement was the Type 918 V8 capable of considering the Elan 635 project was envisioned as having a presumably related 2-litre 4-cylinder engine. - https://www.motortrend.com/news/lotus-esprit-v8/
• -          On the subject of the M220 project, had it been given the go-ahead when was it envisioned to reach production and replace the Esprit?
• -          Speaking of the Elan 635 project and the 635 project in general, due to being envisioned as featuring a 2-litre 4-cylinder engine would it be correct to say the original plan had it reached production was for the model to slot above what eventually became the Lotus Elise or was it a case of the latter growing into a role originally planned for the Elan 635 project?
• -          Additionally was the Lotus Elise always intended to be the recipient of the Rover K-Series engine during its development or were other prospective engines considered whether from outside sources or some version of the aforementioned in-house 4-cylinder intended for the Elan 635?
• -          Know the KV6 was considered for the Lotus Elise Coupe Type 120 prototype (along with the 1.6 V8 twin-turbo from the Suzuki C2 concept) before it evolved into the Type 121 Lotus Europa S, though did the company ever investigate using a V6 like the GM High Feature V6 given the links Lotus had with GM at the time (or some other V6 alternative)?

Am sure there are other missing Lotus tidbits and projects from the list though the above is what stands out.

Edited February 5, 2020 by Lotus Rebel

[The Pits]

Very interesting welcome to the forum. 👍

[USAndretti42]

I heard recently that the Twin Cam indirectly led to the Cosworth DFV happening.  The story is that the original engine had little meat on the cam lobes in line with Coventry Climax design practice.  When Cosworth tweaked the design, it add more metal to allow the profiles to be modified during the development process of the production cams.  This work gave Ford confidence to award the contract for the F1 engine to Cosworth a few years later.

[jep]

As I understand it, Elise was originally a joint venture with Rover. This fell apart when BMW bought Rover. It is therefore highly likely that K Series engine was the first choice powerplant from the outset. 

Justin 

[Lotus Rebel]

Heard some claim there were two missing or seemingly unused Lotus Type numbers in Type 66 and Type 71, both of which have been used in reference to the precursor project at Lotus of what eventually evolved into the Clan Crusader. Type 71 might make some degree of sense in making the Clan precursor a parallel / rival project that lost out against the proposal which evolved into the Lotus Esprit (aka Project M70). 

 

On 01/03/2020 at 22:57, USAndretti42 said:

I heard recently that the Twin Cam indirectly led to the Cosworth DFV happening.  The story is that the original engine had little meat on the cam lobes in line with Coventry Climax design practice.  When Cosworth tweaked the design, it add more metal to allow the profiles to be modified during the development process of the production cams.  This work gave Ford confidence to award the contract for the F1 engine to Cosworth a few years later.

 

Seem to recall reading in Graham Robson's Cosworth - The Search for Power the DFV has a potential displacement range of 2500-4000cc, along with the Kent/Crossflow being capable of growing up to 1650-1700cc that eventually became the basis for the Vegantune Twin-Cam engines.

It is unfortunate Ford UK were lumbered with the Essex V4 instead of producing a slightly bigger Kent/Crossflow 1700-2000cc half-relation that could have underpinned the next step after the Lotus Twin-Cam prior to the Lotus 900 Series engines along similar lines to the Cosworth BDA Series.

 

21 hours ago, jep said:

As I understand it, Elise was originally a joint venture with Rover. This fell apart when BMW bought Rover. It is therefore highly likely that K Series engine was the first choice powerplant from the outset. 

Justin 

 

Was the extent of Rover's involvement with the Elise (besides the K-Series) limited to just the use aluminum via Project Vinland (or another project) or was what eventually became the MGF originally intended to be more closely related with the Elise than it ended up being? 

Speaking of the Elise, found it perplexing the 103 hp 1.4 K-Series was never considered as an entry-level model given it was just as capable of putting out more power as the 1.8 K-Series used in the Elise without being being on a stretched out engine as was the case with the 1.6/1.8 K-Series/etc that helped contribute to the bad rep of the K-Series.

[ramjet]

Welcome to TLF. 

Some interesting reading there. I must admit that my knowledge of Lotus is not that intensive, I just am glad that I had the chance to own one in my lifetime.

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