Tasmin Trailing Arm Design Improvements

[Mr Supercharged]

m2500tvr said:

Don't know how old and cold this thread is. After poking around with this on both a 280i and Lotus Europa, I did design an aluminum clamshell/spherical bearing design that works great. After surveying what the racing crowd seemed to have done successfully to optimize this suspension design on the TVRs and Lotus Europas, I came up with this for my '85 S 1.5 280i. A spherical bearing is the typical solution, but done in a few different ways. In this case, each half of the alloy clamshell fits over the metal frame mounting plate and captures the large spherical bearing. The reliefs in the clamshell provide travel clearance. Had a race prep shop do something similar to this for a full-on track-only Lotus Europa (would have been nice to fit a modern sports or formula racing car suspension and Hewland transaxle, but didn't go that far).

All fits in the stock location and retains all stock dimensions. It does eliminate the evil stepped pin for a straight/single-sized bolt, which eliminates that fragile step in the stock arrangement.

Oh, the only other thing that's popularly done to optimize this Lotus/TVR rear suspension design is to relieve the axial loading/wheel location duty from the drive axle. This is done just by adding a lateral link aligned precisely with the drive axles. With the TVRs, this link is fitted between the diff carrier frame/bracket and the hub/bearing carrier. Did this on the Europa (pre-built part from Richard Winter of Banks Europa); didn't do this with my 280i.

Edited by m2500tvr on Tuesday 28th March 01:31

Edited by m2500tvr on Tuesday 28th March 01:33

Does anyone have the details/sizes of the standard pin, the diameter of the hole the pin passes through in the trailing arm and the length of the pin? Also the hole sizes and spacing for the bush? I'd like to replicate this, possibly for others too prior to taking my car apart. Thanks