Lotus Elan and Lotus Elan Plus 2 Forums

Hello, I am new to this forum (so be gentle with me), I am looking at an alternate power plant for my +2 project, and wondered about the Lotus 2 litre.
I haven't seen any mention r.e such a conversion; anyone know anything about the subject?

A simple and straightforward swop would be a big BDA. Might not be the cheapest, though.

Spyder use the Zetec, it's more complicated, but is cheap.

The Duratec layout is closer to the TC, but my experience is that many true blues will not mention 'Lotus' and 'Vauxhall' in the same breath.

Strange when it's considered that the Lotus 2 litre basically came out of Vauxhall.

Sean

Lotus did have a project to put the 907 engine in the +2.
I have an early Club Lotus magazine showing the design which featured large air vents behind the front wheel and in the bonnet.
No details of engine installation.
The project was cancelled due to U.S.crash test requirements.

The twin cam is mounted vertically the 907/910 engines are layed over at 45 degrees. Do you want to work on the car forever or drive it? I believe the closest thing to a bolt in swap for little money is the 1600 Kent. Same engine mounts location but slightly wider on the later 711 blocks (may just need the exhaust side spacers trimmed a bit, same bellhousing, the height isn't much different so you are left with a custom exhaust pipe/system. If later on you need more power you could put either a twin cam head or BD head. Your call...

Just two cents and change

Gary

Thanks Guys; presumably the 907 could be put in straight, with a drysump? (although that wouldn't be my intention)
Incidently I did my apprenticeship building Ford engines; I vowed never to touch a 711m again! also, the 691 block was (in my opinion) better than the 711, as it was thick walled like the 711, had the square main caps also, but had the smaller and lighter cam follower (not that would make much difference to a twincam!)

The 907 is canted over to reduce vertical(bonnet height) however I assure you the mounting is vertical!
Gearbox?-may need the maxi box with 907 bell and elan tail.
Interesting project which would need some thought!

desprit dan wrote:Thanks Guys; presumably the 907 could be put in straight, with a drysump? (although that wouldn't be my intention)
Incidently I did my apprenticeship building Ford engines; I vowed never to touch a 711m again! also, the 691 block was (in my opinion) better than the 711, as it was thick walled like the 711, had the square main caps also, but had the smaller and lighter cam follower (not that would make much difference to a twincam!)

I guess you did say project Dan, its tough to judge the level of expertise of your first post. It's just that the way I read it, it sounded budget oriented. I would go for the Honda S2000 and gearbox. I don't know how dear they are in where you are but If it fit it would make a nice combination. Zetec is old hat and dead common and duretec's are rather tall. I would have a look over on www.oldschoolford.co.uk for some ideas, nothing is sacred over there...

Gary

Sean Murray wrote:
Strange when it's considered that the Lotus 2 litre basically came out of Vauxhall.
Sean

The all alloy 907 was a Lotus design -indeed Lotus's only engine independant of other manufactures.
True,the head was tested on the cast iron blocks of the Bedford van as the bores centres were similar.This was purely to speed up the design process.

desprit dan wrote:Incidently I did my apprenticeship building Ford engines; I vowed never to touch a 711m again!

Interested to know more about what you didn't like about the 711m


Any more comments on the Vauxhall/Lotus 907 connection ?
( Taking cover !)

Sean

Sean Murray wrote:

desprit dan wrote:Incidently I did my apprenticeship building Ford engines; I vowed never to touch a 711m again!

Interested to know more about what you didn't like about the 711m


Any more comments on the Vauxhall/Lotus 907 connection ?
( Taking cover !)

Sean

Having to build 8 a day everyday for three and a half years!!

No custom fit on one of these is going to be cheap. The developement work has been done with the Zetec though I would disagree with an earlier post and say it is not cheap to do properly. A custom crank and rods, a tall block and work on the combustion chambers will give a Twink of nearly 2 litres but will require quite a bit of specialist machining, but it would fit. A BDA would definitely be a good bet with a custom exhaust or if you were really flash and could find one, a Hart 420R. If I were going for a custom fit myself I would maybe look at the Toyota 4A-GE series.

robcall wrote:The all alloy 907 was a Lotus design -indeed Lotus's only engine independant of other manufactures.

Isn't the V-8 of later Esprits also a purely Lotus product? And no, I am not advocating use of this V-8 in a +2. Many years ago I remember reading Denis Jenkinson's column in Motor Sport. In this one particular column he wrote about a friend who was installing a 2 liter Triumph six in a +2. The sound of a six in a +2 would be nice.

Russ,
Yes a straight six would be great although it would be hard to fit lengthwise and I wouldn't choose the Triumph, it was at the end of its life in the contemporary TR6, with fairly poor performance, rough and heavy (by Lotus standards). Despite their German origin, I think that one of the smaller BMW units would be more attractive.

As to the origins of the 907, it was originally based on the Vauxhall engine. Rob, I think you're unfair describing it as a Van engine. Although it was used in the CF van, it was primarily used in the cars (Victor, Magnum, Viva, Victor Firenza etc). Commercial factors led to Lotus eventually casting their own blocks and taking it all in house. Vauxhall then brought out its own twin cam head and had great success in rallying (Firenza and Chevette HS) although, if I remember correctly, they also got caught using Lotus heads at one point!

Mike

Desprite Dan,
despite opinion that Zetec is a bit old school (cast iron block and not up with lastest engines in terms of bhp/kg), you have to remember that you are putting this into a 40 year old design not lastest Westfield or similar.
The drive train, suspension and brakes will all require tweaks if you increase torque and power. If you go down the pre-designed route using Spyder components, you will not have major issues (ast least with Silvertop Zetec engine) but you will end up buying almost all of Spyder's components, starting with a new chassis.
Suggest you read some of the posts in this forum, then carefully price-up the total job before launching into it. Whichever way you do it, retrofitting an engine into tight spaces in the Plus 2, working around suspension, the existing very tight routing for the exhaust and the "delicacies" of the drive train make an engine swop quite a bit more involved than say same for Escort. I'm assuming that you are talking RHD as well, LHD probably adds to the complications
Regards
Gerry

CBUEB1771 wrote:

robcall wrote:The all alloy 907 was a Lotus design -indeed Lotus's only engine independant of other manufactures.

Isn't the V-8 of later Esprits also a purely Lotus product?

Quite correct Russ,I forgot that one!