LOTUS V SPYDER

[bcmc33]

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.

In my assessment these are probably the most obvious major improvements. The thick tubular crossmember is my major jacking and stand points for the front of the car - you can't do that with the flimsy Lotus crossmember.
TTR has done it's best to strengthen the Lotus design crossmember to stay within racing rules.

[Sundaydriver]

Well , that was a great read , very glad I found this thread.

Speaking from my humble ' lotus virgin ' viewpoint...

Looking at the Spyders Y section at the front , it doesn't appear to be likely anywhere
near as flex resistant as the original design which is for all intents and purposes an 'I' Beam , which is top notch for weight v stiffness, no ? That's to my untrained eye anyway

[marode]

If you drive around with an early Spyder frame, be shure to check the welding seams before you go. They changed this joints now to a design with extra gussets over the bushes where the lower wishbone is welded on to the vacuum chamber. Good idea.

[alan]

hi marode,
imho it looks like the early Spyder chassis welds for the suspension spindles was inferior to the Lotus design. The Lotus design has nice well engineered gusset washers around the spindles but then i am biased

[DABgp]

Dave,

I have seen the standard chassis listed at 4500 ft/lbs per degree - I have never seen a number for a 26R modified chassis. For comparison the same reference has the lotus 79 formula one car with a torsional stiffness of 5000 ft/lbs per degree which would be less that what spyder claims for their frame.

As an aside I have never understood the justification in sacrificing the originality of the car by substituting a spyder frame nor have i seen the claimed improvements manifest themselves in lap-times.

George

ft.lbs per degree, surely?

[gus]

What year is that chassis?

Mine is 1994 vintage with many miles on it and no such issue.

[foggy]

I have a frame from a Early S2/3 coupe No depth to slight rustiness. Needs new under engine cross bar installed.
in Connecticut. Love to find a home. very reasonable
Stefogatgooglemail

[Sea Ranch]

No depth to slight rustiness.

Sorry . . . description a little "foggy" . . . could you clarify, please?

Randy