Zoom lenses for 35mm (or larger formats) faster than f/2.8 are very uncommon, they'd be very large and harder to correct optically. I think the closest you'll get in an FD mount the Angenieux 28-70 f/2.6 (which is really not much faster than f/2.8). There are numerous FD mount prime lenses in that range that are f/2 or faster.
Fastest Canon FD-mount zoom I'm aware of is the 35-70/2.8-3.5.
I don't believe Nikon ever even made a zoom faster than 2.8. Fast primes are the only option.
There is a very nice old Soligor 35-70mm f/2.5-3.5 which I have in a number of mounts. It was also sold under the Access name and maybe also the PMC name.