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Hem

V8 conversion for Excel

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Hi everyone,

I am looking to improve my 1990 Excel by installing a more powerful engine. The question is what should I go for? There is a lot on the forums about the Rover V8, but is this the best upgrade, what are the alternatives?

If I go down the Rover V8 route what can I expect in terms of acceleration, 0 - 60 time, what are the insurance implications and what effect is there on road tax?

Would I be better to keep the existing engine and do various modifications to increase the speed? fuel injection maybe? The main aim for the modifications are to improve the acceleration.

Hem

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I don't think the Rover V8 is necessarily the best option to improve acceleration. It's a heavy engine and old in technology. Also as it's a longer powerplant you may have issues actually fitting it in, although I believe others have managed it. I also don't think it puts out much more than you could acheive my modding the existing engine. The Lotusbits people have had a 912 engine up to about 270bhp, so if you can afford it, that strikes me as a far better solution if as you say acceleration is the goal.

A few people have had success in the Esprit World with V6 conversions using Jaguar/Mondeo engines (they're virtually identical). More modern and lighter powerplants.

In a front engined car, engine weight is something you should consider very carefully with regard to handling.

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On the contrary, it is not a heavy engine (only a bit heavier than the 4 cyl) and is an easy fit. The later 10 bolt engines (4L & 4.6) are better having a stronger bottom end and better ports. Tuning parts cost buttons in comparison to other engines.

It will produce TVR levels of performance when fitted to a light weight fibreglass sportscar, because thats the formula TVR used...

yes, a 912 can make decent hp at screaming RPM, but bhp is just a mathematical function of torque and engine speed (bhp= (torque*rpm)/5252) so an engine that produces 300bhp at 5000rpm has a lot more torque than one that produces 300 bhp at 7500rpm, and will make for a faster car.

Mine spins its wheels on the throttle response in third....(but I do have rubbish tyres on the back).

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Rover V8 is no heavier than the 907/912 lump. V8 = torque and great noise... So what if old technology - still sounds fab and no rubberband cam belt to snap. Plenty of room in the excel/elite/eclat bay and plenty of people have sucessfully installed rover v8. Room too for lexus v8, alfa v6 -mmmm.. and others. Yeah you can spend a fortune modding the 907/912 but there are also many more engines out there with better bangs per buck than the lotus lump.

Best of luck with your car.

Mike

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i´m always wondering why people want to change the lotus engine to something differnt

fact is: the lotus engine does not really develop the power what people think of a lotus..the "body" looks faster than the engine is.

but: this is well known and the engine has enough hidden capacity to get some more horsepower. this is involed with money. so if you want more horsepower, but dont have the money, sell the lotus and buy something differnt...maybe a vauxhall astra diesel?

don´t buy such a car from the beginning, complaining about lack of power afterwards.

thats my opinion.

by the way: here a LHD eclat, converted to a ford cosworth engine:

http://www.carsablanca.de/marketplace/cars/car_detail/38353505

i really can´t agree with this conversion, but for my opinion its much more authentic than a V8....even the sales price is unrealistic..ok..it´s a LHD and its really nice made...but the price is the reason why its up for sale over 1 year (or more?) now.

Edited by Elite7

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The original vs non original debate has been done to death before on the previous forum, and there is little point in reigniting it, but I'm sure something we can all agree on is that the 2+2 cars are amazing handling, beautiful looking practical sportscars.

I'm not suggesting every elite/eclat/excel be converted to something non-original, but having owned an eclat with a lotus engine and owned one with a v8, I doubt I could easily go back to driving the 4 cylinder one. I much prefer the way the v8 car drives and performance is in a different league.

I've yet to hear anyone who has either owned or driven a v8 elite/eclat/excel who doesn't think its a far better car to drive.

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to answer some of the original questions:

1) what can you expect in terms of acceleration? the sky is the limit - plenty of rover v8's in varying states of tune are in use at santa pod. They way it goes depends entirely on the v8 that you choose and the final drive ratio. Pick one from a griffith 500 and it will pretty much go like a griffith 500. My biggest problem is traction and gearing that is slightly too short. I spend almost as long shifting cogs from a standing start as I do on the power. Both issues are fairly easy to fix (better tyres and taller CW&P gearing ratio with an lsd) and I am looking into them at the moment. I can't comment on the toyota final drive ratio and box in your excel as I have no knowledge of them, but they are reputed to be strong.

2) Road Tax? In the UK under the current system, there is no difference between a 2.2 and a 4.6 in an older car.

3) Insurance? Very reasonable. Can't remember the exact figure I pay, but its not much more on this one, than it was for my stock eclat 521.

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Hi all,

We had a few of these types of threads on the old forum - is it a good idea to swap the engine, opinions varying from anything goes - chevy V8, lexus V8 rover V8 etc, some people even thought of putting diesel engines in.... to no it should only be the original Lotus engine etc etc. I've got time for both those opinions, but I've got no problem with modifying the cars, otherwise it ends up going daft with things like 'got to be the original brake pads' etc etc etc...

But the top post says it's with the goal of improving acceleration. For me the V8 conversion is about flexibilty, reliability etc. The Lexus V8 is what I'm fitting to mine, (see other thread), it has more power, but that wasn't the primary motivation for me. My car also is not a mint original example, resale value impact didn't matter as it was not really worth anything to start with.

Cost comes into it as well. Tuning the standard 912 engine looks like fun, but is expensive - and how reliable is a highly tuned 912 engine going to be? The carb version of the rover V8 has got to be the cheapest conversion - hence loads of custom cars using that engine.

As for the weight, I did a bit of research, the Rover V8 can be either slightly lighter or heavier than the Lotus 912 depending on configuration, the lexus V8 is 68kgs heavier (actual measurements). Which results in a 53:47 wieght balance instead of the original 50:50. In my case (starting with the 2.0 907 engine) I'm expecting it to accelerate faster, but more importantly I expect it to pull away from junctions etc more cleanly.

I'm with Dunc on this one, I think it would be sad if there were no original Elite/Eclat/Excels left, but I'd rather see one on the road with a different engine than scrapped. I looked at getting my 907 rebuilt, or fitting a 912 etc but it worked out quite expensive. Mine was too rubbish t live with so it was a case of modify it to work better or sell it.

Cheers, Mat.

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If all you are looking for is better acceleration, change the diff ratio and be prepared to change gear quicker, If you check out what these cars are geared for you will find that they are geared way above what they can achieve in top gear for fuel efficiency and cruising.

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Guest mkelite

my two pennies worth is - as said, this subject has been done to death. your car do what u like but for the money n effort spent why not just restore the car to how it left the factory and accept this was how nature intended it to be. i can assure you in years to come, if not now - cos i believe in originality - original unbastardised cars will be more sought after and appreciated. regards all. DC.

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Hi all,

Thaks very much for the comments / advise.

I can see both sides of the argument but for me I have had the Excel for 10 years and it has now covered 132,000m miles. I re-built the engine when I first had the car and it did make a great difference, now feel it needs something else so I can continue to drive and get pleasure from my Excel. I have no intensions of selling and I also intent to keep the original engine so I still have the option to replace it in the future. I like the look of the rover V8 4.0L as this has been done so advise is available. In am also looking at the other options. Any other alternatives? I do not intent to start until next winter so I can still enjoy driving this year

Regards

Hem

do

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NB Mike at Lotus bits commented on the slight weight penalty at the front from fitting the V8, and suggested that the excel with air con had slightly stronger springs.

Hem,

Go for either the 4.0 or 4.6 versions. These are the later 10 bolt engines with a much stronger bottom end and better heads. The heads have better porting and are have more fat on them for further modding.

don't confuse the 3.9 or 4.2 (14 bolt) versions as they are older and not as good. I have the newer 4.6 block with the older heads (albeit modded), but the newer 10 bolt heads are better and have a higher compression 27cc chamber.

Personally I'd go for a 4.6.

Edited by Dunc

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Mkelite - dunno if you've been across similar discussions on the 'old forum' but there were a few interesting threads about this. From my point of view 'original' is not the mecca that it is to some people. Colin Chapman wanted to do car racing. He only built road cars at all to fund the road racing, and the first few models were literally race rars, or race cars that could be used on the road.

They were built with what was available at the time, the great 'value add' for lotus was the crossover that their racing innovations could bring to road cars - predominantly suspension. also the fact that they were a small scale operation and the cars were hand built meant the time to market was low, so they could bring in advancements to design while major manufacturers would still be discussion finance cases and production/operation logisitcs.

The Elite and Eclat represented a deliberate move by chapman to move 'upmarket', the reason for building the in house Lotus engine was to try to dispell the 'kit car' image that Lotus had. But the downside of being a small scale operation is that Lotus did not have the economies of scale that the big manufacturers had, and had to rely on a supply chain including ford / BL etc parts bins. So to say 'the way nature intended' about Elites and Eclats is a bit of a strectch. They are the best the Lotus could do at the time, and the price break and market sector they were going for. The cars are made to make a profit for Lotus. Perhaps the most obvious example is the chassis - it's a nice design. But it's ungalvanised. It rusts. Through several years of the cars being on the road and getting rusty chassis (including some warranty returns) lotus identified that it would be worth the extra cost of galvanising the chassis in production. The same thing can be said of the rear suspension design, the drum rear brakes, the vacuum headlights, the inadequate Lotus/Beans gearbox, the engine capacity etc etc. Until you end up with the 1992 Excel which is way more sorted and reliable than the original Elite or Eclat.

I can't imagine anyone going 'I'm restoring my car and leaving the chassis ungalvanised as that's original'. If you had the galvanised version available you'd use it surely? Mechanical and elctrical engineering have moved on massively since the car was designed. There is scope to improve the reliability while keeping it a classic car. Which is exactly what Lotus did throughout its (Eclat and Excel) lifespan. If the Elite was not dropped I'm sure the same thing would have happened - ie the Elite Excel with toyota bits replacing all the dodgy bits. So for me modifying the car in in the spirit of Chapman. His willingness to improvise and innovate is what makes the Lotus brand a great one.

And as for investment - The Lotus Elite and Eclat is not in the Aston Martin / E type Jag bracket for classic car values - even though the Elite was more expensive than an E type Jag when it was new. My car was a rough cheap one to start with, so I'm not worried about losing value. Virtually any other investment I can think of would bring a better return. It's just a toy really - a bit of fun. Mine had no MOT when I got it, if I hadn't bought it, the thing could well have ended up on a scrap heap.

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Guest mkelite

gosh thats a really long response to me just saying its nice to keep cars how they left the factory. your cars - do what u will. im fully aware of this old debate but original means in the same spec it left the factory without any unnecc. add ons. go see at a concourse event and read the rules. i dont mean break your neck n be rediculous but just keep the car basically as it was manufactured. each to his own. i just wanted to experience the cars i was interested in as they left the factory. ive had numerous sporting cars and this debate always comes up. i simply was either too young or penniless at the time to buy the car as new thats all............... your cars try what u will but i know what i mean by original. best regards. i wont mention this again................promise. its always misunderstood. DC.

oh and i really must stop posting my thoughts on forums, but laugh as u will, i actually see cars as forms of art first.................so that throws me right out of your discussion about originality then.............regards all from an old duffer. DC.

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My tuppencehapenny for what its worth:

Each to thier own!! I like original cars, however,some improvements can often be made to cope with modern road conditions.

Some folk like to stamp thier own individuality on thier own car, some like a challenge (middle finger to the "can't be done" brigade!).

having modified several cars in the past and restored others to concours standard I enjoy both sides of the argument.

A few years ago I looked at your Elite, David, I was the "berk :thumbup: " that wanted a manual car with leather!! Your coment about the rarity of S2.2 Elites made me review what I was going to do!

I have a manual S2.2 project, my first priority is to get to drive the thing, If I like it (please fulfill my expectations) then I'm planning to "tweak it" in the name of progress. It could get a colour change and a retrim in the material of my choice and most likely a conversion to sequential injection and LPG.

I may get on a guilt trip and keep it closer to standard!

So far it has been further stripped down and recieved a set of speedlines and suitable hubs and it will get a Riviera bonnet. Sadly it has a sunroof, this doesn't fit with my plans but it'll stay for now.

Ideally Lotus would have kept the Elite/Eclat/Excel in production beyond '92. I'd have been in the market for an Elite XL 2.2i....

Ultimately my "perfect" Lotus would be an Elite with all of the late Excel attributes (better running gear/chassis and interior/dash arangement) with an injected engine (better reliability,economy and performance)but thats me!

Prior to his untimely demise, Graham Arnold posed the question about a suitable replacement engine for the Excel, I thought at the time that the V6 Vauxhall Omega engine in MV6 3.2 guise would fit the bill perfectly, sadly it's a bit tall (narrow V angle to fit in front wheel drive Vauxhalls) glorious sound and power though..

Sorry for rambling (and excessive use of brackets)

Mark

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Guest mkelite

hi Mark. i actually regret making statements about originality cos it always goes down the route im not actually referring to................... however YES i fully agree if the S2.2 Elite had all the mod cons of the last Excels id be happy too..............but only if Lotus made it that way! regards all . im not saying anymore your be pleased to read. DC.

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David, don't be intimidated into not posting what you think on here. The more opinions the better. We have the same discussions about Esprits when someone wants to put a V8 into an S1 or S2 and there are always 2 camps, those who want their cars to be as original as possible with all Lotus parts and those who use their cars as a basis for a project. While there weren't many Elites built, there are enough for both camps.

For me, a beautifully maintained and restored original car is lovely to see and we need these so people can still experience them as they left the factory. Even if they have their driveability issues they are nicer than a badly-done or incomplete conversion. However, a nicely done conversion can also be something to admire. And Lotus were working on a V8 that would, undoubtedly gone into the Elite although it wasn't a single-cam, pushrod, bent crank engine. If I saw a nice, original car for sale and nice conversion for sale, I would be more drawn to the original car as you never know about who good the conversion really is put, as Hem never intends to sell the car that's not a concern.

I'll certainly be interested to see how it turns out.

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Guest mkelite

hi Trevor. thanks for that. i just want some friendly banter, meet other owners and to share tech issues on these forums, never to upset any one. that would just be too heavy................ im fully aware of the history of Lotus in quite intricate detail and about what they were developing etc so it seems odd when someone tries to explain things in triplicate. but i think i will remain quieter. best regards. DC.

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Hi, I concurr, everyone should feel free to express their opinion - just as valid to say 'I prefer to keep it original' as 'I prefer to modify to make it work the way I want it to' - I don't think there are any right and wrong answers on this; you asked the question 'why not restore it to original spec', and that's the answer (For me). A different person would give a different answer and I've got no problem with that. In short, my car was too difficult to drive, leaking oil, difficult to start, potenially unreliable (read expensive to fix) for me personally to live with. Definitely not a criticism of people who want the car original, i agree it would be a real shame if there were no original examples left. Incidentally I went with the toyota engine, which ironically is the same configuration as the Lotus V8, four overhead camshafts, 32 valves four litres. The difference is it's fuel injected etc. As lotus had the tie up since about 1983 with toyota, it's a pity they didn't have a go at fitting the toyota V8 into the Excel, properly developed it would have been a great car, especially when you think about what Lotus did with the Vauxhall Carlton engine - I guess they were still at the stage of using a lotus built engine that they'd spent a lot of money developing. Cheers, Mat.

Edited by mat grant

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I was chatting to a chap in a garage in Norwich a couple of weeks ago, he worked at Lotus during the late 70s early 80s and rekons they built up and possibly ran a Rover V8 with 900 series heads, now that would be an interesting concept..... He seemed to think the bore centres are the same as the 900 series.

Mark

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Chat to Ralph. Apparently there was a V8 based on the 900 series engine, I believe it was a bit too powerful (something about really only needing one gear as it would be able to pull away in top).

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Chat to Ralph. Apparently there was a V8 based on the 900 series engine

Yep, the type 909, have seen it on the factory tours.

909.jpg

On the same tours (sorry to go over old ground as we all know this) we were told the modern Lotus V8 was originally a development engine for a front engined car and that the last esprit was going to have been the S4s, but the V8 lump ended up in there with the spare italian 2.0L engines making the GT3 and giving the Esprit a few more years. Brian Angus could tell the story better.

:unsure:

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It was meant for the Lotus Etna and in fact now the one 909 Lotus had is in the one Etna rolling chassis, owned by a chap in Holland I think!

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