LOTUS V SPYDER

[abstamaria]

[quote="ardee_selby"Andy, Not in the least "stupid" !!!!! This image has stuck with me for some reason.
Cheers - Richard[/quote]

Wow, Diana Rigg on a Lotus chassis. I had never seen that before! Thanks, Richard.

Andy

[abstamaria]

Going back to the original query, I think the ?tightness? of the original-framed Elan is probably due to its more compliant, original suspension, the silent-block bushings, the insulating strip inside the doors, maybe the tires, etc., rather than the frame.

As to whether to install a Lotus frame or a Spyder, I think the choice will depend on many factors, including what one intends to do with the car. Will it be raced, a weekend car, or a daily driver? Perhaps, the other performance cars that the owner has will affect the decision, too. Jay Leno, with access to a McLaren F1 among others, might prefer to retain the experience of a standard Elan.

I have a 1948 MG TC, whose steering is heavy and has (to a Lotus driver) a frightening amount of play. This is typical of TCs, so a popular mod is to replace the steering box with one from a VW ? a great improvement. I decided against that mod because I have an Elan, which has the most surgically precise steering in the world (I am biased). What a difference it is to drive the TC after the Elan and to say to oneself ?this is how a TC drives.? If I had the VW box in there, the experience would not be so satisfying, in my opinion.

I also was quite lucky in that I had for many years two Lotuses that outperformed the Elan: a 1963 23 with a TC engine and a 1998 S1 Elise. On the track, the 23 was just so much quicker, and no amount of tweaking could bring the Elan to its level. After all, the 23 is an out-and-out racing car. The Elise I felt was sublime; it represented 30 years worth of new technology. After both, it would have been so refreshing to drive an original Elan, especially one on skinny 155 Dunlop SP Sports, and feel the tail slide out so predictably. The Elan was always with you and would never embarrass you. ?Your mother would sooner trip you on your way to collect the Nobel Prize,? wrote Road & Track. True.

Alas, I had prepared my Elan for racing. I installed special dampers, adjustable springs, rose joints all around, racing A arms and wishbones, magnesium wheels with Dunlop racing tires, etc. (all vintage racing eligible, by the way), and now it is too difficult to revert to completely stock. It is easier to buy another Elan, but mine has been with me too long for me to consider a replacement. But, if I did, I would look for a standard specification Sprint. One with a Lotus frame.

A Ferrari, they say, is the engine, with the rest of the car thrown in for free. A Lotus is the chassis and suspension. If one installed a Spyder frame and Spyder?s own rear suspension, one might have an improved car in certain respects; but would it be a Lotus?

My opinion only. I am glad we have these discussions to keep our common interest going. May it never be settled.

Regards,

Andy

[bcmc33]

Andy

I agree the original frame is a beautiful and elegant piece of work which is why I have the oringal one I removed my my Elan hanging in my house as a light fitting

cheers
Rohan

Picture, Rohan, Picture.

Archives, Brian, archives.

http://www.lotuselan.net/publish/article_351.shtml

Cheers - Richard

OK, OK, Richard, but I've noticed for some time now that you're so much better than me at the archive stuff.

[ardee_selby]

OK, OK, Richard, but I've noticed for some time now that you're so much better than me at the archive stuff.

P'raps I'd have had more success as a bean counter! "S*d tomorrow...what about yesterday?"

Cheers - Richard

[alan.barker]

I would look for a standard specification Sprint. One with a Lotus frame.

many many thanks Andy,
i have exactly that, a 1972 Elan Sprint fhc on Dunlop 155 SP sport Aquajet and Lotus Galvanised Chassis fitted by Miles Wilkins.
Lagoon Blue over White. It always puts a smile on my face every time i drive it, so small but so dam fast
I love the Sprint as it was meant to be, full of life and fantastic to drive.
Alan B

[abstamaria]

You are a lucky man, Alan.

Andy

[stevebroad]

After comparing the spyder chassis with the original Elan one, and talking to Tony Thompson (I know he has an axe to grind re Spyder), I fail to see the advantages of the Spyder chassis over the standard one, let alone one that has been 26R'd. Anyone able to quantify the advantages? Is it actually torsionally stiffer or just form over function with a touch of the Emperor's new clothes?

[GrUmPyBoDgEr]

After comparing the spyder chassis with the original Elan one, and talking to Tony Thompson (I know he has an axe to grind re Spyder), I fail to see the advantages of the Spyder chassis over the standard one, let alone one that has been 26R'd. Anyone able to quantify the advantages? Is it actually torsionally stiffer or just form over function with a touch of the Emperor's new clothes?

Steve,
your argument is pretty soundly based when you ask about torsional stiffness.
The subject Spyder Frame is not a new one & that particular question has not been answered as far as I know.
However the arguments for choosing the Spyder frame are, amongst others, more available space around the engine bay & back axle, front uprights less liable to rusting, removable wishbone pivots, removable lower frame brace.
Another point not often mentioned is that a bent or broken tubular structure can be repaired whereas a buckled or bent steel sheet fabrication will never acheive its original stiffness/strength after straightening.

Going back to the stiffness bit, my decision to go the Spyder route was based on the above reasons but also, purely subjectively; seen from my eyes the backbone of the frame just looks to be a stiffer structure than the Lotus Elan/26R alternatives.

There is no doubt that the TTR stiffened 26R frame is an excellent piece of kit.
Nevertheless it is a frame that is compromised by the regulations laid down by historic racing reg's.
It is therefore a must have for those who drive in competitions but as I have written before; I wonder how many of those competitors would prefer to fit the Spyder part if the reg's permitted it?

Of course that frame also provides a super solution for anyone who wants to have what to a large extent is "original spec."


What is the basis for your argument apart from stiffness or originality ?

Cheers
John

P.S. I've yet to be sucked in by "the Emperors new clothes" tricks.
But I suppose my time will come

[bcmc33]

After comparing the spyder chassis with the original Elan one, and talking to Tony Thompson (I know he has an axe to grind re Spyder), I fail to see the advantages of the Spyder chassis over the standard one, let alone one that has been 26R'd. Anyone able to quantify the advantages? Is it actually torsionally stiffer or just form over function with a touch of the Emperor's new clothes?

Steve,
your argument is pretty soundly based when you ask about torsional stiffness.
The subject Spyder Frame is not a new one & that particular question has not been answered as far as I know.
However the arguments for choosing the Spyder frame are, amongst others, more available space around the engine bay & back axle, front uprights less liable to rusting, removable wishbone pivots, removable lower frame brace.
Another point not often mentioned is that a bent or broken tubular structure can be repaired whereas a buckled or bent steel sheet fabrication will never acheive its original stiffness/strength after straightening.

Going back to the stiffness bit, my decision to go the Spyder root was based on the above reasons but also, purely subjectively seen from my eyes, the backbone of the frame just looks to be a stiffer structure than the Lotus Elan/26R alternatives.

There is no doubt that the TTR stiffened 26R frame is an excellent piece of kit.
Nevertheless it is a frame that is compromised by the regulations laid down by historic racing reg's.
It is therefore a must have for those who drive in competitions but as I have written before; I wonder how many of those competitors would prefer to fit the Spyder part if the reg's permitted it?

Of course that frame also provides a super solution for anyone who wants to have what to a large extent is "original spec."


What is the basis for your argument apart from stiffness or originality ?

Cheers
John

You beat me again, John, as I was in the process of writing a reply that contained your salient points.

I have the original Spyder stressed skin frame which, as I understand, was produced due to the fact that a Lotus replacement was not available. These frames were made to a level that addressed the known failure/weak points of the original Lotus frame. Realizing there was a market for replacement frames, Lotus stopped the Spyder production claiming it infringed their design, and started marketing their own original frames.
Spyder reacted to this with the space-frame design that was found to be much stiffer.

It has to be said, however, that for the "ordinary" Elan driver, the extra stiffness means 'diddly-squat', but for the driver that does some level of competition or track days, the extra stiffness is well worth while.
I personally would like the space-frame design for maintenance reasons alone - so from that point of view there is no competition.

[ardee_selby]

Brian,

I have the original Spyder stressed skin frame which, as I understand, was produced due to the fact that a Lotus replacement was not available. These frames were made to a level that addressed the known failure/weak points of the original Lotus frame.

Is there anywhere that details how the weaknesses were addressed?

It has to be said, however, that for the "ordinary" Elan driver, the extra stiffness means 'diddly-squat', but for the driver that does some level of competition or track days, the extra stiffness is well worth while. I personally would like the space-frame design for maintenance reasons alone - so from that point of view there is no competition.

A silly idea to think of military applications, ILS, etc, perhaps, but in my mind if a RAM-D analysis of the options were carried I suspect it would be "no-contest".
Re: "ordinary"...at the end of the day it's "horses for courses" and any judgement must surely take account of intended "conditions of use".

I would like to hear Peter & Allisons viewpoint (http://rallyelan.com/)

Cheers - Richard

[UAB807F]

Brian,

I have the original Spyder stressed skin frame which, as I understand, was produced due to the fact that a Lotus replacement was not available. These frames were made to a level that addressed the known failure/weak points of the original Lotus frame.

Is there anywhere that details how the weaknesses were addressed?

I also have this type of Spyder chassis and if I'm honest I can't tell you all the detail changes or even if they are noticeable in normal driving, but I can recall some. The rear suspension mounting points are braced and also the lower diff. rod mounts. (like the 26R ?) The most obvious changes were around the front crossmember & uprights which were closed by welded plates to prevent the accumulation of mud & salt and they no doubt help to stiffen the structure. The vertical uprights are also braced against the horizontal crossmember, which is tubular instead of the welded square section of the original.

I realise my old Lotus chassis had been "lightened" by rusting away over it's 12yr life but even now I can remember being surprised at just how much heavier the Spyder one was when you compared them side by side. I can only put that down to either thicker steel or additional local reinforcement.

Does the car handle differently ? I don't know because I only had a worn out chassis to compare with which had cracks around the differential & engine mounts and front vertical uprights. I do know I had the choice of buying either Lotus or Spyder, same price, same dealer and both lying alongside each other for me to look at. I took the Spyder one simply because I thought it looked a better product at the time and there were obvious changes to the areas which had failed on my old chassis.

Brian

(and even back then it was as controversial as it still seems to be today ! )

[nebogipfel]

I also have this type of Spyder chassis and if I'm honest I can't tell you all the detail changes or even if they are noticeable in normal driving, but I can recall some. The rear suspension mounting points are braced and also the lower diff. rod mounts. (like the 26R ?) The most obvious changes were around the front crossmember & uprights which were closed by welded plates to prevent the accumulation of mud & salt and they no doubt help to stiffen the structure. The vertical uprights are also braced against the horizontal crossmember, which is tubular instead of the welded square section of the original.


Brian

(and even back then it was as controversial as it still seems to be today ! )

There are obviously a few of us running around with the original stressed skin Spyder chassis............ and very happy with it

[garyeanderson]

Please

Just argue the original aspect, I doubt its even close contest as far as strength goes with a stock Lotus replacement in galvanized or bare steel. Maybe the TTR 26r replacement is a better comparison to the Spyder space frame but its more money.

Its your money spend it how you want!

Gary

[Sea Ranch]

Really appreciate your comments, Andy, on Leno, MG TCs and the original experience.

I have to say, that's just where my heart is, too. Am looking forward to being able to "rebuild" my car (which is very original), as opposed to doing a "replacement" job on it. Will have to see how viable the components are when I get there, I guess.

I'm not a racer; just a guy who loves old cars and wants that sentimental experience (and the great thing about Lotus is that it's also a wonderful driving experience, even in this day).

ps. thanks for that gorgeous top view pic of the rolling chassis!

[garyeanderson]

I too have read that the Spyder space frame is "50% stiffer". I have always wondered what that meant. I am not sure how much the chassis contributes to the overall structure of the Elan. If the chassis/subframe is 50%, and the body unit of a type 26 is 50%, then the Soyder space frames type 26 should be 25% stiffer. My guess/suspicion is though that the chassis on the type 26 is less than 50%, I do not know but if the chassis was 20% and it was 50 Stiffer in twist then something on the order of a 10% overall increase in torsional stiffness would be achieved. My guess is that the 50% number by itself is not very useful in telling us the whole picture.
Maybe on an S4 where the body has been economized with a bit less fiberglass, its a bigger increase in overall stiffness.

you pays your money and takes ones choice, that is unless you have a good chassis/subframe to start with and then your choice is easy.

Gary