I don't want to be the forum sponsor that jumps in on everything with "hydroboost" "hydroboost" "hydroboost', but if you have power steering (which is the power source for the hydraulic brake assist unit instead of vacuum), we can take both of your cars and make them stop like a dog hitting the end of its chain. The Wilwood package that you already have installed at the wheels will be plenty suitable for autocross and road course, so I wouldn't change a thing at the wheels, just move up to a 1 1/8" bore Wilwood 260-8856P (or BK if you prefer the black version) or the Wilwood 261-13270P if you want the knob adjustable proportioning valve on the package. Then install this direct bolt in package:
http://www.hydratechbraking.com/GM_1stgenF_Body.html
Note that if you didn't want to touch brake fluid during installation (even I'm getting to the point where I hate that stuff), you could leave the existing 1" bore Wilwood MC in place, leaving the brake lines connected to the MC at all times while only swapping out the vacuum booster for the hydraulic booster, then evaluate how you may like it running the 1" bore existing MC - some like it and never do move up to the 1 1/8" bore MC saying it's "just right". It also provides a very exact comparison of back to back improvement, as literally nothing else has changed in the brake system except for the brake assist unit. If you find the pedal a bit lighter than you prefer, then you could swap in the slightly larger bore 1 1/8" Wilwood MC at any later date as a tuning mod. The usual case is that the customer is so used to having to stomp down on the pedal so hard to stop the car, that they then have to retrain their "brake foot" entirely to accommodate the vastly more powerful braking actions for a few hundred miles, so we tell them not to make the MC swap until they have driven the car a while. Jim always tells people "if you have the 1" bore MC, run it" !
Install the same package into your other car with the stock disc / drums and you will be blown away that it will stop just as hard as your other equipped with the upscale Wilwood brakes at the wheels. Both cars will stop equally as hard, BUT the stock disc / drum car won't be able to do it as many times in a row as the Wilwood equipped car, simply because the stock brakes can't cool as quickly as the Wilwood disc brakes can in between hard stops.
We have customers that just cannot believe how well their stock disc / drum brakes respond to the installation of only our hydraulic brake assist system. They write us / call us in disbelief, which makes us smile. They of course expected some improvement, but got WAY more than expected, stating it was one of the best mods they have ever done on any car in their lifetime as far as bang for the buck, overall fit / finish / appearance, and pedal feel so much crisper and responsive than expected.
Soooo.... Take a look at this as an option, providing you have power steering. If you would like to discuss, give my guy Jim a call:
http://www.hydratechbraking.com/contact.html
Might anyone else that has installed one of our systems possibly chime in? It always helps to hear it from just about anybody else other than the manufacturer...
Or? Swap out your pads to the more aggressive (but dusty / noisy) Wilwood BP20 pads on the Wilwood car, and then install semi metallic aggressive pads and shoes on the other car. The largest problem I see is the almost useless 7" vacuum booster. With those silly little things, you may as well be dealing with a manual brake car for the miniscule amount of actual power assist they provide - maybe 150-200PSI of additional brake line power assist if it is a dual diaphragm model, even less if it is a single diaphragm version. It's like using a Chevette vacuum booster, designed to stop a itty bitty tiny little car.
Have a happy and safe 4th of July! 10 toes and ten fingers please!