[SoCal LS-L]

No brakes as in no brake assist?? Or just none at all.......

If the pedal feels soft or just goes to the floor you need to bleed the air out starting at the rear wheels first (in order from farthest from the master cylinder to nearest last).

If the pedal is solid but you have to press really hard to stop, check the vacuum line to the brake booster, which is the usually black round thing behind the brake fluid reservoir. This needs engine vacuum to power your brakes, maybe a vacuum hose (usually big for brakes) wasnt connected properly after the headgaskets were done, starving the booster of vacuum. Good luck!