Trunnions

[Tazio]

When were trunnions replaced and the existing style of wishbone brought into service?

[AdamQ]

I think they overlapped didn't they?  I bought a live axle kit new from Caterham in 1999 and that had trunnions and the De Dion Seven I currently have, which was also bought new in 1999, has the existing wishbone set-up.  

Or did the De Dion cars originally have trunnions and you're asking when they were changed to the existing set-up?  If that's the case, then I'm afraid I don't know the answer.

I converted my live axle car to a double top wishbone set-up and that was a very straightforward process.  I can't remember if that involved changing the uprights, but I think it probably did (ISTR trying to sell the old uprights at some point).

In the hope that that's of some help at least ...

Adam

[Tazio]

Just looking at an older car, a 92, and I expected trunnions, but the car doesn't have them, then it also has the wrong wheels and wrong badges.....lol

[Tony P]

I think the ball joint at the bottom of the upright made its debut with the introduction of the (16v) Vauxhall-powered cars (ie '91), but I'm sure, as Adam says, the two styles then overlapped (particularly in the case of live-axle and Classic cars). 
(Intro of de Dion pre-dates the 'non-trunnion' development - and rear disc brakes too - by quite a way.)

[Tazio]

Many thanks.

[Keith_T]

My old H-reg De Dion had Trunnions like my '98 live axle Classic.  So there was quite a long overlap.