The chassis fitted to TR4A's, TR250, TR5 and TR6 are in essence the same, particularly where the front suspension attaches. The brackets welded to the chassis that support the lower inner wishbones, are a weak point. Triumph were aware of this as, without an official recall, TR4A's (and later TR5 and TR250) were modified by dealers when ever an unmodified car appeared in their workshops.

The official modification consisted of a strengthener welded to one side of the chassis support bracket. This was effective to a point but by the time the TR6 arrived additional strengtheners were added. Whilst better, this level of improvement was not quite enough and chassis' continued to fail. Our kit will provide all the parts for a comprehensive fix. You may need to replace the lower wishbone brackets 148691 (second hand available too 148691SH and powder coated black 148691SHPC ) as the studs are often damaged. A thoroughly better bracket RTR3287 is available, see below.

This kit is a combination of replications of the original strengtheners and RevingtonTR developed additions. In particular our kit includes a strengthener, which fits behind the support bracket to double the thickness of the metal where the lower wishbone fulcrum brackets (part number 148691) attach. This proved important, as the side strengthening of the support bracket moved the weak point along the chain to the lower wishbone fulcrum bracket stud attachment holes, resulting in the studs pulling though the chassis support bracket rather than tearing it off the chassis, which happened previously! If the original chassis brackets are too badly damaged to be simply strengthened, and new ones are required, the part number to purchase is 139580. See below

The increase in metal thickness by adding an additional plate behind the lower fulcrum bracket adds an extra 3-4mm ,as a result  you are likely to run out of thread if using fulcrum bracket 148691 so brackets  with longer studs is almost certainly going to be needed. RevingtonTR have produced such a bracket. This bracket with longer studs will certainly be required if negative camber is to be set. Order part number RTR3287 below.

This strength kit can in be fitted with the engine and the body in place.