1965 Oldsmobile Cutlass - Get A Grip!
The Bench Seat Slidefest Comes To An End With Real Seats And Harnesses.
From the February, 2011 issue of Popular Hot Rodding
By Stephen Kim
Photography by Robert McGaffin
Techno geeks like babbling about poor weight distribution, wacky camber curves, and negative steering axis angles for proof that muscle cars were never designed for hard cornering. Tough guy talk like that might impress your online girlfriend, but come on boys, it's really not that complicated. Just look at the seats in these cars, for cryin' out loud. That's all the proof you need right there. Even factory bucket seats of the day offered up less lateral support than the captain's chairs in a modern minivan, and grandma's bench seats were even worse. And just in case drivers ever contemplated opening up the windows during a thunderstorm and converting their bench seats into an impromptu water park slide, the OEs made sure to cover a bunch of them up in mass expanses of slippery vinyl. With the suspension and tire technology infused into the typical Pro Touring machine, the problem gets exponentially worse, as we experienced firsthand with Project Olds.
We're still not sure how he did it-maybe he strapped himself down with a boatload of gaffer's tape-but Photo Editor Robert McGaffin somehow managed to prop himself upright during his '65 Cutlass' numerous autocross and road course excursions. Nonetheless, he admits that sliding around the cabin made staring in the face of high-speed tracks like Road America even more intimidating. With Project Olds now mopping up on the autocross, and even more outings on the horizon, the stock bench seats and lap belts had to go. In addition to their lack of lateral support, the bench seats had to be lifted up slightly in the front to clear the transmission tunnel, which was raised during the Tremec five-speed swap. This resulted in an increase in stress on the lower back, making long road trips very unpleasant. Moreover, the shifter came awfully close to touching the seat in Second gear. To fix these maladies, and prevent our man Bobby Mack from getting tossed like Lindsay Lohan the day after rehab, we bolted up a new set of Procar Elite seats and a five-point Crow racing harness.
The stock bench seats in a...
The stock bench seats in a '65 Cutlass are a great place to spend time as long as the steering wheel stays straight. With a complete Detroit Speed and Engineering suspension and gooey Nitto R-compound tires, the Cutlass changed directions laterally much better than its occupants.
Helping us out once again with the install was Randy Johnson of D&Z Customs. Johnson's made a living out of building and racing g-Machines, and we put his expertise to good use. Swapping out a bench seat for a set of buckets is rather straightforward, and only takes an afternoon of work. Since Project Olds doesn't have a rollbar, however, it requires coming up with a creative solution to mounting the shoulder harnesses. There are several ways to do this, but Randy came up with a clever and inconspicuous solution. So if your g-Machine is generating more g's than its seats can handle, here's quick look at what it takes to get buckled down.
Not only are factory lap belts...
Not only are factory lap belts inadequate for holding the driver in place during extreme lateral maneuvering, nearly 50 years of wear and tear have degraded their ability to perform properly. The belt buckle is too large to pass through the crack between the bottom cushion and backrest, so it was unbolted from the floorboard first, then removed with the seat assembly.
Before bolting down a new...
Before bolting down a new seat, you have to figure out where to position it. For cars that see competition duty, it's imperative to sit in the car while wearing a helmet to ensure that there's adequate headroom. With the seat bracket mocked up onto the seat, the entire assembly was placed in various spots on the floorboard. Once Mack found a comfortable seating position, the four mounting hole locations in the seat brackets were marked onto the carpet.
The antisubmarine not only...
The antisubmarine not only prevents the driver from sinking into the floorboard, it also serves as an anchoring point against which the shoulder harnesses generate tension. It can be bolted to the floorboard, but we chose to attach it to the seat bracket instead. After measuring out the center of the front crossbar support, Randy Johnson drilled out a 7/16-inch hole.
With the chalk marks serving...
With the chalk marks serving as a guide, Johnson cut away just enough of the carpet to access the floorboard. The spots were then marked out with a transfer punch before drilling out four 7/16-inch holes for the seat brackets.
After deburring the holes,...
After deburring the holes, the seat brackets were bolted to the floorboard and the crotch strap was then attached to the seat bracket. Since these are highly stressed attachment points, using high-strength Grade 8 bolts is a good idea.
The lap belts use eyebolts...
The lap belts use eyebolts to attach to the floorboard. It's easiest to install them before the seats are in place. GM put lots of time into figuring out the ideal mounting spots for the lap belts, so screwing the eyebolts into the stock boltholes works best.
If headroom is limited, the...
If headroom is limited, the seats can be bolted directly to the floorboard. Since this isn't an issue with roomy A-bodies, we were able to bolt Procar's slider assemblies to the bottom of the seats, which were provided with the brackets. This resulting fore-and-aft adjustability allows for further fine-tuning of the seating position.
At 30 pounds, the Procar Elite...
At 30 pounds, the Procar Elite seats are substantially lighter than the stock bench. The slider assembly on the bottom of the seat slips right over the floorboard-mounted bracket, and then bolts down to the bracket rails at all four corners.
One very handy feature about...
One very handy feature about the Crow lap belts is that they clip onto the floorboard eyebolts. This facilitates quick and easy removal. Many belts bolt directly to the floorboard, and removing them requires wrestling with a ratchet in a cramped space.
With the lap belts and crotch...
With the lap belts and crotch strap in place, the last step was installing the shoulder harnesses. We opted for a V-type shoulder harness that uses a single attachment point for the left- and right-side shoulder straps. The angle from the driver's shoulders to the shoulder belt mounting location should not exceed 20 degrees. Angles greater than 20 degrees can cause excessive spinal compression. Mounting the straps at angles greater than 20 degrees to horizontal will put additional stress on the attachment point, and render the harness less effective at limiting driver movement. To achieve the proper angle in Project Olds, Johnson removed the rear seats and marked out an attachment point in between the rear driver-side lap belt mounts.
Unlike the lap belt eyebolts,...
Unlike the lap belt eyebolts, which screw into factory boltholes, the attachment point for the shoulder harnesses were drilled into the rear seat area. Attaching them securely with a nut requires using a large 3-inch washer to help spread the load placed on the eyebolt.
As with the lap belts, the...
As with the lap belts, the shoulder harness clips onto the eyebolt for easy installation. Should the rear seats need to be used, the harness can be quickly detached. Its positioning in the rear seat area makes it easy to reach between the bottom cushion and backrest.
The Crow five-point harnesses...
The Crow five-point harnesses features a cam-lock fastening system as opposed to a more primitive latch-and-link setup. Special thanks to RideTech for providing us with the harnesses. After hitting the autocross with the new seats and harnesses, Mack reports that they keep him cinched down far more effectively than the stock bench, which gives him the confidence to hammer on Project Olds even harder. And actually running your g-Machine hard-instead of merely talking trash about how it supposedly handles as well as a new Corvette-is what it's all about.
|WHERE THE MONEY WENT
|Procar Elite Seat (left)
|Procar Elite Seat (right)
|Procar seat bracket (left)
|Procar seat bracket (right)
|RideTech five-point harnesses (2)
|Eyebolts, nuts, washers
|THE COST SO FAR
|'65 Olds Cutlass
|DSE four-link suspension
|DSE front suspension
|Baer front and rear brakes
|DSE brake booster
|DSE steering kit
|Strange S60 rearend
|SAM 461 big-block
|Hurst five-speed trans
|Custom Hooker exhaust
|Canton Accusump system