Fitting a Series 3 servo as an upgrade?

[288gto]

I have seen mention of this, including Peter's book, but can't find any further details. I notice from their web pictures that Eagle do this as well to their cars.
This would be for a Series 2 car with the intention of also fitting Zeus or Coopercraft calipers.
Has anyone got first hand experience of this?

Is this a straight swap?
Is there increased servo assistance?
Are the bore and volumes of fluid displaced greater?
Do I need to change the master cylinder?

Thanks in advance,

Simon

[PeterCrespin]

It's a straight swap if you can squeeze it in. The front support bracket may need tweaking and the band clamp loosening to get the hoses lined up. The hydraulics are identical AFAIK, but being a larger drum you get a bit more assistance. Good S2 brakes are fine as-is, I only fitted the S3 servo because I had a new one handy. If you've got knee problems I suppose slightly less pedal effort is worth having but I wouldn't bother doing it again.

Pete