early and late rear suspension interchange

[Pascal's pilot]

Hello all,

This is probable a question for Malcolm but all info gratefully received for any source.

So there I was sat at the MOT garage reading my Haynes R4 manual while waiting for the wife's Pug 107 to be MOTed.
Carefully reading about late rear suspension set up etc.

Mr Haynes says that the early and late suspension arms are NOT interchangeable ?
Page 322, para 19.

As far as I know, early cars ( relatively early say 70's) have pressed steel arms. mostly with a (PCRV) pressure conscious reducing brake valve.
Late cars have cast arms with an (LCRV) load conscious reducing valve.

As I am in the process of trying to fit late parts to an early chassis this is rather important point.
I have converted left to right hand drive.
Fitted a floor mounted park brake.
Have the bits to convert front to disc brakes.
About to start changing my early arms for late ones to get rear park brake drums and LCRV located on the arm. (would I be wasting my time?, can it be done ?)

Advise and help please.

I don't get why they would not be interchangeable because as far as I know there is only one replacement chassis (fits all years) ?

cheers Dave.

 

[malcolm]

You can fit the late rear suspension on an early car. I think the late chassis has a couple less mounting holes so it's the early suspension that won't fit the late chassis.

 

[Pascal's pilot]

Phew, thanks Malcolm.

Onwards.

Regards Dave

 

[angel]

Early suspension arms will also fit late chassis without having to drill holes. At least that was the case with a 1979 chassis that I fitted 1972 suspension on.