TRANSMISSION TUNNEL

Transmission Tunnel Setup

As much pride as Dan, RJ, and the team had in Big Red, they also knew that a lot of temporary fixes and a lot of small updates had diluted some of its luster, especially in the cockpit. The first gauge cluster was located between the dash and the transmission tunnel.

In 1987, Bill Osborne made the transmission tunnel fit a manual transmission for the purpose of running high-speed open-road racing. He never imagined Big Red also would end up running an automatic transmission for Land Speed/Top Speed events. Additional clearance between the transmission and firewall will be a welcomed change. The curved bulge on top of the tunnel was added a few years back to make room for running an automatic transmission. Before then, it was flat across the top. The guys couldn’t wait to break out the cutting torch!

Dave went up to the rafters to find his 4L80E tranny case for fitment. With the case mounted behind a bare 454 engine block, and some of the transmission tunnel cut out, it was easy to see how much more needed to be changed. Shawn, Tim, and

Dave (left to right) called a meeting to discuss what changes should be incorporated in the new transmission tunnel plans.

After removing all the unneeded firewall and old transmission tunnel, Dave started building the rear section of the transmission tunnel. Once the rear tunnel and removable tunnel cover flanges were created, Dave started building the center of the firewall and transmission tunnel arch. From there, he used his straight edge to form a smooth transition between the front and rear flanges.

Dave modified his trusty, old vice-mount Williams Lowbuck Tools shrinker/stretcher with a section of aluminum channel so he could use it by hand. Here he’s stretching the flange on the new tunnel. A smooth transition here will allow him to create a removable transmission tunnel cover — much easier.

With all the stationary pieces finally installed permanently, Dave started creating a cardboard template for the removable cover. Once it’s finished, it will be attached with quick-release Dzus fasteners. This will allow the crew more access to inspecting and servicing the transmission, clutch, and road-racing starter from the top side.

Transmission Tunnel Setup