Mod Rocket


Story By Per Schroeder

Some say that autocross competition is a lot safer than road racing, and for the most part that’s true. However, that doesn’t mean cone carvers should forsake safety in the quest for more speed. While the SCCA Solo rules aren’t quite as stringent as the ones governing road racing, our B Modified LeGrand project still needed some substantial safety equipment. After all, this autocrosser is capable of eclipsing speeds of 70 or 80 mph—even on smaller courses.
Our car was restored for vintage race use about five years ago, and while all of the necessary safety equipment was in place, it required updating. We also needed to evaluate our personal gear. Time to get our safety on.

Sit Down, Hold On

A set of new Schroth Clubman harnesses were inexpensive and would hold us snugly in our new sprint-style karting seat.

You can tell if a sports racer is an older model by simply checking out its cockpit. The early ones usually have some space for a passenger, with the driver’s seat offset to one side—often the right. By definition, a sports racer was required to have room for two, although that passenger space was rarely big enough for a human. The original drivers’ seats were also somewhat crude. In most cases, the driver simply sat in a semi-reclining position on the bare aluminum tub. There was no foam padding or any other provision for comfort.
The bareback driver’s seat in our LeGrand didn’t work with our preferred driving position, so some changes were in order. First we tried using a sheet of high-density foam padding from BSCI to create a more upright driving position. Ultimately, this didn’t provide enough lateral support for our torso.

We fabricated a set of aluminum brackets to mate the seat to our car’s aluminum monocoque.

After looking at a variety of seating options, we chose to cut down a sprint-style kart seat. A kart seat is designed to hold a driver in a semi-upright position while enduring high lateral g-loads. It was almost exactly what we needed.
We ordered a $50 seat from an online karting supply shop and cut the bottom to fit our car’s angled aluminum floor. To prevent the now-trimmed fiberglass seat from flexing, we riveted a pair of brackets between the seat and the chassis.
We also needed to look at our harness. The belts that came with the car hadn’t seen much use, but their expiration date was upon us.
Race harnesses age out after just a few years: SFI-spec harnesses need to be replaced every two years, while FIA-approved versions need to be replaced every five. Our car’s Sparco FIA cam-lock harness was approaching that five-year mark, and it needed to be replaced or rewebbed.
Replacing the entire kit with Schroth Racing’s new Clubman belt package turned out to be the more affordable option. This cam-lock harness is available in a limited variety of end types and adjuster styles. By keeping these options to a minimum, Schroth is able to retail the high-quality, FIA-approved product for less than $200. We used the existing eyebolt mounting points for the supplied clip-in ends.

Calling a Lifeline

Our car already sported a full on-board fire system, but since it was out of date we were tempted to simply remove it. In a class where every ounce counts, the extra 10 pounds for an extinguisher bottle, lines and fluid were less than ideal. The Solo rules don’t require onboard fire extinguishers or systems, but after some thought we decided to keep a system in place.
For one, we knew we’d sleep better at night by choosing safe over sorry. We also predicted that our finished car would weigh less than the class minimum of 1020 pounds, so we decided to add ballast that would make us safer rather than just serve as dead weight.
We replaced the entire fire system with a new, lighter and more compact Lifeline Zero 360 unit. This system saved us only 3 or 4 pounds, but its compact size allowed us to easily position the tank behind the driver. We mounted it toward the left rear of the car, which should help our corner-weighting values.
The Lifeline system is probably the easiest one we’ve ever installed. The lines are made of a special Eaton-sourced plastic and feature push-on connectors and T-junctions. That means we didn’t need to flare aluminum lines, a task associated with most traditional onboard fire systems. A system like ours retails for about $845.

Safety Cell

We had Fuel Safe recreate the custom bladder for $900. Then we used a pair of half-gallon displacement blocks to bring the capacity down to 4 gallons for autocross use. Every pound counts, after all.

While we reviewed our car’s safety equipment, we took a good, long look at our fuel cell. It was a 12-year-old custom Fuel Safe bladder that was starting to delaminate and leak. It needed to be replaced.
Like fire systems, fuel cells aren’t really covered in the Solo rules. However, since we wanted to keep the car legal for both road racing and Solo use, we sent our 5-gallon bladder back to Fuel Safe to be replicated.
We received the new piece a few weeks later, along with new internal baffling foam and several half-gallon displacement blocks. The total bill was about $900 for the custom bladder and accessories; good custom work is not cheap.
We stuck the blocks in the cell to cut its capacity from 5 to 4 gallons. We don’t need more than 3 or 4 gallons to make it through an autocross event, even with multiple drivers. Plus, this move should drop about 7 pounds from the left front and improve the car’s final crossweights.

Personal Gear

Finally, we needed to take a look at our personal safety gear. Unlike a production-based car, a sports racer exposes its driver to the elements, even at autocross speeds.
We first upgraded to a new SA2005 closed-face helmet. While the SA rating isn’t an absolute necessity for Solo use—technically an M-rated helmet designed for motorcycle use is legal—we decided to take advantage of the fireproof liner that accompanies the Snell Foundation’s SA designation.
The closed-face style wasn’t up for debate, though. Thanks to the LeGrand’s seating position and open cockpit, an open-face helmet would make its driver ripe for a rock-and-bug facial. We ordered an OMP closed-face helmet that fit perfectly.
We also needed a pair of shoes that could maneuver in the narrow confines of the LeGrand’s footbox. In this case, a pair of Pilotis fit the bill.

Stepping Stones

One of our LeGrand’s first big outings was last year’s SCCA Solo National Tour in Cecil, Ga. We were the lone competitor in B Modified, but we wound up turning fast times that were respectable for the class.
We gauged our times against George Bowland’s A Modified special; we beat George in PAX index on Saturday, but he nipped us on Sunday. All in all, we were very happy with how the car performed in its near-baseline condition.
Now we can start the major surgery, including a differential conversion. We’ll also bump up our displacement for a bit more power and torque, trading our 850cc Kawasaki engine for one with KZ1000 specs.
Now the fun should really begin.

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