Chassis stiffness

The press in the 60s quote Lotus as saying the Elan?s bare chassis had a torsional stiffness of about 4,000 lbs per degree of twist and generally say it?s a good figure. MInd you iirc the Triumph Stag?s body had around 7,000 lbs per degree after they added the ?T? bar over the cabin. My question is twofold:

  1. Does anyone know how much additional stiffness was given by bolting on the body to the Elan?s chassis?
  2. What?s the stiffness of the Plus 2 chassis; I?d imagine it?s less than the Elan?s but does anyone have any figures?

Read this, it offers an interesting perspective

ferraritestarossa.net/clublo … x.html#top

Rob,
That?s a bloody good read! Thanks for posting …

I?m meeting Ron Hickmans secretary next week, hoping for some more stories to report on here.

That’s a great story ! :slight_smile:

Alan - is that Maureen who occasionally posts in here ??

Regards
Richad

Hi Richard,
Yes that?s her, Adam (PastaPesto on here) is organising a little tour of Cheshunt and Hornsey next week and Maureen is coming along. I think that Adam is posting/has posted details for anyone who wants to join in.

Life sounds so much more fun then, great read.

Peter

The body does add significant stiffness. When the rules forced Peter Pulver to remove his lightweight body and put on a regular one the car was actually faster. Paul Newman?s mechanics at Bob Sharp tested their Elan and found the torsional stiffness was very good but they found the car very flexible in the horizontal plane
Eric 64 S1

I gather with the latest FIA spec cages an Elan becomes a space frame car.

What a brilliant article and many thanks for posting the link - lots of insights into how Lotus operated in the early 60s - interesting that it says the production chassis didn’t even get up to 4,000 ft lb per degree!