How about a stainless steel chassis with extra features?

[bill308]

OK, I admit it, I like corrosion resistant materials. Why couldn?t the usual suspects offer a corrosion resistant chassis, maybe made of stainless steel, with some extras?

If I were going to spec out a the chassis, I?d make it to 26R specs., and I?d want it made out of a stainless steel, with good corrosion resistance, physical properties equivalent to or better than the current mild steel, excellent weld-ability, and reasonable cold working properties to accommodate bending in a sheet metal brake. Welds would have to be sound and corrosion resistant, so the right welding rods would have to be used. Welding would also have to occur with a minimum of distortion, so the right sequence of welds and their duration might be important.

The extras might include adjustable suspension inboard pickup points. These pickup points would be adjustable by shims, like any other modern car, using a fork type of pickup as is used on Ferrari 308?s, but with the ability accommodate stock elastomeric or plastic bushings, or rod ends. This would effectively make the stock suspension adjustable, without the need to purchase, purpose made, adjustable A-arms.

Another extra to build into the chassis might be provision for a T-9 or similar gearbox, with an appropriate tail housing support made available.

How about increased strength in areas such as torque rod pickup points, engine mounts, or a touch more clearance for the differential? A removable, under oil pan brace, of course.

Maybe accommodate a large bore exhaust system, a rear anti roll bar, and a safety roll bar?

Who wants one?

Bill

[Verve]

SOUNDS FANTASTIC !!

[steveww]

While you're at it could you make some bodies in carbonfibre Now that I think about it why not make the subframe in carbonfibre also. Strong light weight and will not rust.

Welding up some stainless is a bit old fashioned. What about bonded aliminium like the Elise? May be if you are making carbonfbre bodies re-engineer the whole thing, do away with the separate subframe and turn it in to a monocoque. You could get the weight down to about 400kg. That would give the Caterhams a run for their money

[thor]

I'd like to sign up for my 400kg T9 +2 now please.

[Emma-Knight]

oh, I would like a riveted aluminium chassis, airframe-style in silver with chromate green sections... flush riveted of course!
Stainless steel would be nice too... though I must admit Loties original
frame is still there and in good shape! I thought about spyder like
drainage holes in the front cross member, to allow inside anti-corrosion treatment.

[type36lotus]

Can we also engineer a little additional room for the Merlin engine?

[steveww]

No the Merlin is a bit too heavy, this would give a bit too much understeer and a big lump of an engine like that is not really in with Lotus design principals. IMHO the Powertec V8 is the better option
http://www.powertecracing.com/v8_index.php

[Emma-Knight]

Used a Merlin camcover as bird watering device. It was damaged during
the Battle of Britain filming and beyond repair. Still nice for the birds...


Anna

Ever looked at the Y-gear of a Merlin? So what's a waterpump...

[elansprint71]

Bill,
Not a metallurgist then?

Pete.

[bill308]

Verve,

If a 26R chassis costs 1600 GBP, would one of stainless be worth say 2000 GPB?

Steveww,

I really don't want to recreate a high tech Elan, merely make the one I have more durable at a reasonable cost. If I was going to do a whole car, I might do something like a slightly larger Lotus 23.

thor,

I'd like one of those too.

Emma-Knight,

Riveted aluminum chassis? Interesting. If I went down this route, I'd probably incorporate bonding along with the rivets. This can produce a much stronger joint if properly done. Aluminum is not the best chassis material in my mind because unlike steel, if properly done, can have near infinite fatigue life. Allowable stresses in aluminum have to be held much lower for good fatigue life.

The other issue is that I'd like it if the chassis would remain legal for vintage racing. If it is super lightweight and totally unlike the original, it's unlikely the chassis would be legal. On the other hand, if the modifications and basic construction really don't yield a competitive advantage, then maybe there is a possibility they could be considered acceptable. Adjustable inboard suspension pickup points would a competitive advantage but not more than what can be obtained with adjustable 26R A-arms, just cheaper and easier to adjust and would use the stock A-arms.

Drainage holes and maintenance accessibility are good things to keep in mind.

Merlins? A few years ago I went to an air show a Pratt and Whitney, (air craft engines) and I remember the wonderful sound a 12-cylinder Merlin makes at full tilt. A P-51 Mustang was making high speed, low altitude, passes over the airfield.

elansprint71,

Not a metallurgist Pete, just a practicing mechanical engineer with a love of competition and toys.

Any more ideas?

Bill

[trw99]

I was just wandering ........ about the possibility of an aluminium Elan chassis. So I did a search and came upon this thread, which it is probably worth continuing but substituting aluminium for stainless steel.

With the aluminium bonding technology and experience that Lotus have gained with Elise, Europa and Evora, could they make up replacement Elan chassis using the same materiel and bonding? I am no metallurgist so have no idea of the technicalities involved here, but it struck me that such a replacement chassis (provided it was painted the correct and original colour, of course!) could be rather helpful.

Any views anyone?

Tim

[MintSprint]

...re-engineer the whole thing, do away with the separate subframe and turn it in to a monocoque. You could get the weight down to about 400kg. That would give the Caterhams a run for their money

I think you'd find that surprisingly difficult: I own a carbon-fibre monocoque 'Seven', designed on a clean sheet of paper by an Ex-Lotus F1 Chief Designer, with a much lighter engine than the Lotus Twin Cam, no windows, windscreen/wipers or doors, specially designed ultra-light wheels and hubs, lightweight battery and wiring harness, etc., and it's still some way heavier than its original design target weight of 400kg.

A carbon fibre monocoque Elan would certainly be much stronger and stiffer than the original, but I think you'd find that the weight improvement wouldn't be as dramatic as you might hope.

It's a nice daydream, though...

Back on topic: I'm no metallurgist, either but given the standard mild steel backbone's propensity for fatigue cracking, I wouldn't want a stainless steel chassis unless it had been beefed up to the point where weight would be unconscionable.

[msd1107]

The Elan body weighs 200 lbs or so. The chassis is under 100 lbs. This compares well with the weight of the monocoque Elite.

Tony Thompson carries replacement bodies at varying weights if you can live with a roadster. His lightest body saves almost half the weight of the standard body but is not really usable on the street.

If you were to go to a carbon fibre replacement body, probably make it a FHC and engineer in all the mounting points necessary. That would save the weight of the chassis, as well as benefitting from the weight savings of the carbon fibre body and the increased stiffness of the monocoque body.

But 400 kg is still rather an unrealistic goal. Even with all the weight saving tricks you can think of, 470-480 is more realistic. Still, even with a streetable 160 hp twinc, the performance would be quite good. Say sub 4 sec 0-60, 160 mph top end. Pretty current figures.

TT's replacement bodies are around $7,000 (haven't looked at his catalogue recently). I doubt that a CF FHC could be brought in for less than 30K in small production quantities, even if most of the R&D was contributed. Since this is not race eligible, how many street drivers would buy such a thing? (Well, I am a light weight freak, so might be interested) But this is interesting, I and have heard various snippets of conversation on the subject.

David
1968 36/7988

[persiflage]

Merlins? A few years ago I went to an air show a Pratt and Whitney, (air craft engines) and I remember the wonderful sound a 12-cylinder Merlin makes at full tilt. A P-51 Mustang was making high speed, low altitude, passes over the airfield.

Bill,
If the sound of a Merlin at full chat rocks your boat, then I must recommend that you take a trip across country to the air races at Reno (every September).
The Merlins running at the races are producing almost twice the power that they were during the war!
Get to the out field and await the start of the Unlimited races ... now imagine the sound of the one Merlin multiplied by 8 or 9 or 10 possibly combined with the sound of Griffons, Centaurus and some large P&W radials all passing over your head in the space of about 30 seconds at no more than 40ft altitude
... but you do not have to imagine it ... you can experience it!
Do it once and you will be hooked.

[bengalcharlie]

bill,

I remember the existance of a plus two with full stainless steel chassis and fitted with a alfa romeo engine in the north of the Netherlands. I am sure if you would contact the dutch lotus club they could get you into contact with the owner.
If I would still live in a part of the world with severe winters I would also consider the idea but in the north island of New Zealand the weather is very mild all year round
cheers
Robin