My first post in this forum and definitely not the last!!

I've just put BA XR6 front suspension and FG XR6 brakes into my AU1 S Falcon and hence found that BA shockers are longer than the AU1 units. As a result I've reinstalled the original AU1 shocks and springs but would like to upgrade the springs with lowered ones.
The AU1 sits higher than the AU2 and 3, however the AU1 S model, as far as I understand, is lower than a standard AU1 forte or the like. Does anybody know what springs I could put in the front to lower the car 20-30mm.

Also, with the original AU1 brakes being similar to the brakes on my push bike, aka tiny, I am wondering if the master cylinder is up to the task as the peddle feels a bit spongier now with the bigger brakes installed. Is it worthwhile getting a BA/BF master cylinder given the size difference in the brakes.

Any info is greatly appreciated!!

Cheers

gearbox-suspension-brake-driveline-f4/problem-master-cyl-or-booster-t116674.html
AUII/BA dual diaphragm booster with an AUII master cyl - one with similar specs to your car, as the split point varies with the car type (e.g. sedan/wagon/ute), and rear axle (live or IRS).

Cheers snap0964,

I'm thinking of trying to replace the entire braking unit with a BA or later unit, going to talk to my mechanic/s about it to see what might be involved. Thanks for the link and info, learning more everyday!!

Onwards and upwards!!

Probably best to stick to what I've suggested for all round braking balance, the AUII-FG std front calipers have the same piston swept volume, and there's no difference in the rear volume from AUI to AUII.
This keeps your setup reasonably close to the manufacturers setup - they've done all the testing, so research well, brakes need to be spot on, too late to find you've come up short when you need them most.
The AUII master cyl front primary has about a 30% increase in fluid capacity than the AUI/EF/EL setups, hence why you find spongyness, as the fluid flow isn't keeping up.