Lotus Elan Chassis

A look at the details of a Lotus Elan chassis

[@archsailor]

I had a 1966 Lotus Elan. Loved it. However, every time I got on the throttle, the lights went down. Exciting to drive at night!

[@PaulH_S2_Elan]

Very exciting 😯. Odd though, I would have thought more throttle would have created more vacuum.

[@isleofauto]

Really interesting video! Your walk around brings this ingenious engineering masterpiece back to life!

[@smartiecooper4702]

Excellent run through, provides some good pointers for anyone looking at a possible purchase. Ran a Lotus 20 for a while, flimsy construction is a understatement. The Elan chassis also looks flimsy but is a brick outhouse by comparison.

[@seancain7305]

Great video, thanks for explaining the Lotus design features

[@davidparry1982]

Amazing in its simplicity but also genius - the use of the front cross member as a vacuum reservoir for the lights - did not know that

[@fifedrum5753]

Really good video only one slight contention. It’s not a chassis it’s a sub frame. You can drive a chassis you cannot drive this. I won this argument with HMRC over an imported S2. DVLA consider it a sub frame because the vehicle details are attached to the body. But great vid.

[@michaeltb1358]

Now that is a nice real Elan chassis. Only later ones were fully galvanised. My 1967 original did not rust so badly anyway. I gave up the doughnuts for a UJ conversion which improved gearchange and ride. I believe later conversions used CV joints. Description of the vacuum is wrong it just uses the vacuum produced between the carbs and inlet valves. Many early Fords used this suction to drive the wipers, which caused problems as the vacuum dropped when the throttle was opened. When the headlight operating cylinders leak on the Elan the lamps drop when you accelerate. This was a problem on early models as the cylinders used a piston with a leather seal. Later there was a diaphragm.

[@Rob-fx2dw]

I can recall seeing those vacuum operated wipers in operattion on 1950's vehicles. It was rather amusing with them accelerating greatly then almost stopping right when you didn't want such variation in their speed. One instance was during a drive in movie when a lot of cars started their engines to get the wipers operating as rain squall came across during the penultimate partt to the end of the movie as the critical last few scenes were becoming obliterated by heavy rain.

[@phillycheesetake]

Such a glorious piece of design, my dream car.

[@beatthedevil1396]

I have a lead on an s3 not sure of the year. Guessing 67. Needs full resto

[@ikedee649]

excellent video overview Paul,. very useful !

[@Rob-fx2dw]

Great video - Thanks for that presentation. I have not seen one as good about the Lotus Elan chassis I wonder if it would not be wise to apply a type of silicon type sealant to that noise dampening fabric so the chassis does not get wet and cause rusting.

[@PaulH_S2_Elan]

I'm glad you liked the video. Thanks for your comments. Regarding the noise damping, I have seen others use a closed cell foam instead of the original material. However, when I took the body off the original rotten chassis, that area was in the best condition. It seemed that it was well protected from the wet.

[@AaronQuinnn]

Great info. Thank you for the walk through!

[@alro2434]

Thanks. Also, the motor mount cracks never got any worse, so I never thought that the engine was going to go anywhere.

[@PaulH_S2_Elan]

That's good to know. Thank you.

[@DL-ls5sy]

Bright and clever

[@jimestall413]

Very professional Paul. And very wise to not fit the driveshafts until the body goes back on.

[@frankhoward7645]

What's the advantage of waiting to fit the driveshafts until after the body goes back on?

[@PaulH_S2_Elan]

Because there is very little weight without the body the suspension is at it's lowest position. With the driveshafts in place the rubber donuts would be stretched by the angle of the driveshaft. Better to fit the rubber donuts when the suspension is loaded so the driveshafts are more or less horizontal which will put the least amount of stress on the donuts. (Sorry for the very slow reply).

[@FirstLast-tx3yj]

@@PaulH_S2_Elan it is 1.2mm steel all around?

[@PaulH_S2_Elan]

@@FirstLast-tx3yj It's not all 1.2 mm. There are also parts made from 1.6 mm.

[@FirstLast-tx3yj]

@@PaulH_S2_Elan how does it compare to other types of chassis when it comes to tosional stiffness? For some reason I expect it to feel not rigid

[@georgesheller6054]

I’m sure there was a leak so the available vacuum was not enough to keep the lights up

[@kentakeda9424]

It's very light weight!

[@GialloOcra105]

Thank you for sharing.

[@PaulH_S2_Elan]

My pleasure!

[@alexday5892]

Is that an original Lotus chassis or Spyder ?

[@PaulH_S2_Elan]

Hi, It's an original Lotus chassis. There are at least two Spyder designs; one is a space frame version and the other is a sheet metal more like the original Lotus design.

[@alexday5892]

@@PaulH_S2_Elan It’s looking good for an original chassis. Did you have a hoist for the body removal or was it a handful of mates and some elbow grease ?

[@PaulH_S2_Elan]

The chassis is a genuine Lotus replacement chassis purchased from a Lotus dealership many years ago. It one of the last from Lotus and is galvanised. You can still buy the original Lotus chassis, now supplied by Classic Team Lotus :) but I believe they don't have them galvanised anymore. With all the components removed from the body it's an easy lift for 4 people, and that 's what we did with mine when it was lifted off and put back on.

[@jareknowak8712]

Did i heard "40 kg"?

[@PaulH_S2_Elan]

Yes, you really did. The bare chassis weighs 40 kg (88 lb). Once this sheet metal chassis (or sub frame) is bolted into the body moulding it makes an incredibly stiff structure. The bare GRP body weighs 90 kg. Maybe you've seen the video that explains more about the body: kzbin.info/www/bejne/pHewhZ2Elr6Ins0 The Elan is truly a lightweight sport racer.