Time To Race!

This project made a race fan into a driver, one with the knowledge of what is required to build a race car.

No, Patrick Manzi didn't win his first race, nor the second. As a matter of fact, he hasn't won yet. The first race night, our fan-turned-driver started 22nd and finished 14th. I should tell you that seven cars didn't finish. In all fairness, Patrick did well in his first race. He stayed on the track and came in with only one small battle scar. In the heat of the race he did pass two cars before driving in too hard and getting loose. He did a creditable job of gathering it up before he was pointed the wrong way.

The Car Setup

Our friends, David Williamson and his son Aaron, who are also competitors at Auburndale (Florida) Speedway, had a few suggestions after the first practice. The first was to lower the car, which we did. We used shorter, stiffer springs in the front.

We lowered the chassis height from 6 inches to 51/2 inches, as measured at the front end of the outside chassis rail. We also lowered the rear to 6 inches at the rear of the outside chassis rail. This lowered the front and rear roll centers, giving the car's weight more leverage against the spring.

In order to keep the right-front, lower A-frame from bottoming out against the chassis we went back to a 1,400-pound-rated spring. We had started with this rate on a taller spring. The left front spring used was 1,150. Because Auburndale's rules specify that the free height of both front springs be the same, we had to be selective in choosing our Afco springs. The rear springs used rated at 250 left and 225 right.

A note here: If you cut springs to achieve a height, you will be making the spring stronger. To keep the same rate, you must start with a weaker spring. In doing so, a spring rater is a must. Unless you want to spend a lot of time (and money) playing with springs, go to the manufacturer for solutions.

How It Works

Our engine from JR Motorsports has run flawlessly. The power range is smooth and predictable, something a beginning driver needs. Throttle response with the Competition Carburetion Quadra-Jet is crisp. Patrick has appreciated these things on the track. He has gained experience in the eight race nights he has run. He has learned to trade some orange paint for some other tones. The bumpers have taken abuse, but have held up well although not as pretty as they were. Patrick now has a third-place finish in a feature to his credit.

Patrick's average lap times fell in the 16.5 to 16.7 range--not far from the 16-seconds-flat laps run by the track's top Street Stock drivers. We have had only one failure in the car. I think it was a design flaw on my part more than anything else. TCI built a good transmission for this car. It worked well until it received some outside abuse. For a number of years I have built stock cars with two rigid engine mounts in the front and one flexible rubber transmission mount at the rear. Well, after several races the Turbo 350 transmission's bellhousing cracked. The crack opened to the point that the torque converter shaft pulled out of the transmission.

A postmortem revealed the most likely problem. Remember our rules called for no bracing of the chassis in front of the firewall? Well, past the firewall, the chassis assumes the characteristics of well-cooked spaghetti. With the rigid front engine mounts, this flex caused the bellhousing to be the most rigid member in this area of the chassis. It also became the weakest in tensile strength.

So, was there a metal flaw in the bellhousing? Not likely, but I don't send transmission cases out for X-rays either. Did the paved-track traction exert more load than the dirt tracks I'm used to? Quite possibly. My recommendation is to use all rubber flex motor/transmission mounts when rollcage bracing does not extend past the firewall.

Performance

As a Street Stock built for the class rules of Auburndale Speedway, the car is fast. In this competitive class, Patrick is getting some quick lessons. His finishing positions are getting better. He has yet to fail to finish a feature race. The cracked bellhousing happened with another driver at another track. We built the car and raced it. It ran creditably well. We turned a race fan into a racer. Goal accomplished.