During the same discussions a member explained his uprated "stop" light system by doubling in the rear "fogs". We rushed from the pub to view the effect revealing an impressive result but with unwanted side-effects. The rear fog warning lamps came on when the brakes were applied and the "stops" came on when the rear "fogs" were on. Not good! However it seemed promising so I further modified my "stop" light system to produce 84W of warning without those unwanted effects.

Do you need to do these modifications?

Well, both tail and stop lights on SD1's are quite dim compared to modern vehicles so simply to reduce the chances of being "shunted" make it worth considering.

In the mid '90's the Bedford region discussed the merits of improved SD1 tail lights by substituting the 21W "stop" lights with conventional 21W/5W "stop/ tail" holders/bulbs and wiring the extra "tail" filament in parallel with the existing 4W bulb, which itself can also be uprated to 5W. Thus, a normal system which used only 8W can be simply uprated to 20W without any "tail" light exceeding the 5W limit.

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