There were several goals established when the twin cam project first began. At the top of the list was creating an naturally aspirated engine that would not sacrifice the benefits of Volvo's long runner intake. Four valve engines are well known for their excellent breathing characteristics at higher RPM. The B234 intake was designed to extend the power curve further down into the rev range so the car would not seem anemic at lower speeds. Therein lies the problem. A stock B234 intake will clear the master cylinder, but will not leave sufficient room for an efficient air intake, even with the short, 960 throttle body.
Turbo fans have developed several solutions to the clearance problem. Shorter, custom fabricated intake manifolds are available the leave plenty of room for the stock master cylinder and brake booster. Some people have also taken to cutting two inches out of the intake runners of the stock manifold. Of course there were no 240 turbos after 1985, so such modifications, including the custom manifolds and turbo installation, would be impossible to certify in California without certifying the new intake first. A very pricey proposition. Certainly there is always a way around that, but we chose a different route, based on wanting to keep the stock intake.
Our first stab at creating room for the master cylinder was a partial failure. We created a fixture to offset the master cylinder down and to the right, where it tucks below the intake system. Elegant, strong and sturdy, very neat to look at.....and a failure. Not enough study was done on the physics of levers, and we were left sadly without full braking power. The car is driveable, and we've enjoyed it so far, but not a long term solution. Currently we are desiging a two stage hydraulic system to activate a remotely mounted master cylinder.
The development of the brake M.C. fixture is still worth sharing!
Defeated by physics. The lever, suspended on one end, looses much of the force applied to it depending on how close the pivot point is to the application of force. In this case, with the pivot point only a couple of inches from the push rod, most of the booster's strength was lost. To work, it would have to be a compound lever setup with a second lever attached between the existing one and the MC's push rod.
The (unrealized) goal here was to use a lever, activated by the booster, to remotely activate the master cylinder. Lots of good parts used....
The actuator rod runs through a tube mounted to the plate that attaches to the booster.