Project: Dirt Tracker Building an IMCA chassis

They used to race on dirt out of necessity.

Now they race on dirt out of insanity,

modified dirt racers rule. And today we're going to the track before we start crashing on our own horsepower modified race machines.

Hey, welcome to what may be the wildest, most radical horse power ever.

You know, we love building muscle machines for the street and strip, but today we're breaking some new ground. Literally.

You see there's a growing legion of enthusiasts who love to build and race their own modified cars for the dirt track. Well, like the thrill seekers, you're about to meet at a typical event out in Lincoln, Nebraska.

There ain't nothing I've found yet that gives you that kind of adrenaline rush.

It's just the biggest rush coming in that corner side by side with somebody trying to keep your car off them and keep your car from spinning out.

That's just, that's the biggest thing that keeps me in it.

You're just out there to try to get the position when wrecks happen.

Ain't nothing you can do about it

with its dusty dirt track beginnings in 1915

I MC A is the oldest racing sanctioning body in the country today. Its legacy lives on

at places like Lincoln, Nebraska, where state champions will be crowned in three categories,

hobby stock and stock, plus the headliner class, open wheel modified

easily one of the most exciting and challenging forms of four wheel competition.

Why do we do it,

competition

and the fun.

We love the competition. Our driver loves to win.

Their driver is Chris Alcorn who's raced about 50 times a year after leaving the drag strip six years ago.

They are equally as fun. But, uh, this one just lasts a little bit longer.

It's a pretty good time. You kind of get to talking to yourself and trying to manipulate the car to do what it does pull on the steering wheel. You think it does something but it doesn't really do anything but

it gets, you kind of get you going

if you ever talk to the car.

Oh, yeah.

Yeah.

Come on, come on, stick, stick. Oh, you know,

you talk quite a bit

as you apply the brakes. You can turn this car here back and forth and it changes the falcon point on the master cylinders that apply either more

front brake or rear brake. Most modified motors run on alcohol over gas and either way the idea is to make horsepower as cheaply as possible

since I MC A has a $525 engine claim rule. Yeah, I've been claimed probably six or seven times in my career.

And, uh,

it's not always fun, but hopefully you don't have your best piece in there. When they, when they, when you do get

claimed,

he runs a swing arm suspension system, he and his crew will adjust for ever changing track conditions during the race. If it's good, you can

maybe fine tune a little bit. Like we may go down to the bottom hole on the bird cage to make it

more aggressive. Well, maybe even bring it up to get around the long corner after some hot laps to warm up the cars and pack down the dirt. It's time for heat races where drivers bump and battle for a spot in the all important a feature

in modified heats. The competition is furious ferocious and features a few pretty scary moments,

but he's alright.

Well, Chris has his hands full but manages a 3rd and 2nd place in his heats to put him well into the eight feature.

Feel pretty good about maybe winning this thing.

Yeah, I do feel pretty good car was really strong. Uh I

think we'll do some improvements. It was off of what it did in the heat race and I think we'll,

I think it'll be all right.

Finally, the big show where the top modified the wild open wheel warriors of dirt track racing clash in this battle to the finish

where horsepower is a lesser weapon than a driver's skill.

Well, he fights off a couple of serious challenges. But when the checkered flag comes down, Chris Alcorn

claims another victory in his 10 year career. His first ever here in Lincoln,

all victories are good. But how does this one stack up? This one's right on top because it's, uh, we've come here and ran so well and

leading it a

year or two ago and one of those tires over there jumped out and got me and,

oh, I was like four to go or something. And it was,

this is, this is awesome. Always wanted to win here and finally done.

You'll never get rich racing on dirt. It's all about the thrill of competition

and the ultimate excitement that comes from crossing the finish line in your modified race car

and walking away a winner.

Well, that's some pretty wild stuff. Are you ready for a taste of that? Yeah, I've been ready ever since we left Lincoln.

We got a lot of work to do before I get any seat time that we do. Well, you keep your seat, we'll get to work on our own modified racer right after the break.

Mm. Nothing like the smell of Methanol on a Saturday afternoon.

You know, we love horsepower no matter what kind of car it's in. And well, the car we're building today is a modified racer, much like this one that's owned and raced by Ferris Lovett and it all starts with the chassis and for that we're headed back to Lincoln to visit America's oldest speed shop. A place where speed has been part of the name and company game since 1952.

When we witnessed the thrills and sometimes spills of modified racing on dirt, we were pumped up about starting our own build up.

And while in Lincoln, Nebraska, we knew just the place to go Speedway Motors founded in the fifties by the legendary Speedy Bill Smith.

Uh I can remember being in high school and

having somebody call me a gearhead and I thought maybe that was a bad

uh name.

But uh

today I like it.

Racers love the idea that Bill's Speedway Motors has become a supermarket for anything to do with racing, the parts that can be at their doorstep when they need them.

So you got to have a lot of inventory, a lot of inventory. We have over 25,000 parts that we inventory here at speedway

and over $10 million in inventory currently on the shelf.

In addition to parts, the dirt track racer can get quality machine work here too.

Maybe he needs a crank to be fully balanced for an engine setup.

Ok. There we go.

Another crank

to go out.

Maybe he needs a set of rods recy

or other machine work in his mission of building a competitive yet affordable power plant.

The affordability of the I MC modified is the key,

the rules in the class and the way the class is structured. It appeals to the grassroots, you know, racer,

the guy that's going to work 40 hours a week and do this as a hobby.

Your modified car has got to start with the chassis and speedway helped us here too with all the pipes cut, bent and welded together to make a solid, safe rule friendly foundation.

They also helped us with the rear end, a Ford floating nine inch that will later fill with 31 spine

axles.

Well, here it is our brand new I MC A modified chassis. Now for about 2400 bucks, you can't beat the price of this thing. They start out with the metric frame and build up from there including all the mounting tabs, upper and lower control arm mounts, jackpot locations, motor mount brackets, drive shat loop and hey, even a cage for the fuel cell. Now, the first thing we need to do before we get it back to the shop is send it out to the powder coders. Yeah, let's go for yellow with the color. Now, if we wanted to go out and get our own donor frame spend well, a couple of months fitting fabricating and in our case, pulling out our hair Speedway Motors offers this kid here that has everything we need and would save about 1700 bucks. But

I think we made the right call for my money

while we were here. The speedway guys helped us with a parts list to fill out that new chassis

parts that will help us break into round track racing without breaking our budget.

Here it is back from the powder coat looking fine and ready for a build up. You know, we got our work cut out for it and today we're gonna go ahead and mount the rear end, all the front suspension and even hang the body pretty much everything except the drive train. So stick around. We'll see you after the break.

Welcome back to the horsepower shop and our first adventure in dirt track racing

in case you just caught up with us. We're building our own I MC, a modified race car

and we got our chassis from a place called Speedway Motors in Lincoln, Nebraska.

We're also using them as a source for all these parts that we're getting ready to install. We're going to start with the rear. Now, during the break, we already preassembled some of the components to our rear end. Now, this thing is a full floater which means even under an axle failure, our grand national hub will stay in place along with the tire and wheel. Now, speaking of axles, I'm going to go ahead and install this 31 spline piece

that's also a little larger in diameter to make for a good axle seal

and they're held in place with these small o

ring caps.

We also preassembled a pair of bird cages on the rear end along with the caliper bracket for the stock GM CALIPER we have to use. Now, the bird cage is the main mounting point for the rear end. So first we'll attach the links,

notice how the bird cage used as a Teflon bearing. This allows the rear end to move up and down freely without any binding.

Next, we can install this pan hard bar. Now, this thing is fully adjustable and keeps the rear end from moving side to side in the car. It attaches to this bracket that's mounted on the front of the rear end and has an adjuster to allow for, to change opinion angle. Now, the other end attaches to this bolt on bracket on the frame rail.

Next is this pull bar. It mounts to the link mounts on the rear end. It's got a progressive spring that dramatically increases whenever it's under a load, it's fully adjustable and allows the rear end to roll forward and back whenever torque is applied.

This 9010 shock here mounts between the top link and a chassis mountain. Well, what's it do?

Well, let's say you're making some good speed down the straight away and you break hard into a turn.

This horizontally mounted shock prevents the rear end from slamming forward violently and eases its movement

to finish up the rear. We're using a coil over kit with a Bill Stein shock that has a nine inch stroke. Now, there's a number of different configurations you can do on the rear ends of these cars leaf spring, Zlin or four bar like ours. However, the rural state, you must use a minimum five inch diameter spring

I MC A requires us to use a racing fuel cell inside a minimum 18 gauge steel container.

Ours is 32 gallons which is the maximum allowed and we're mounting it inside this removable cage and securing it with these solid steel straps.

It's got to be mounted behind the axle and between the rear wheels. Now we can go ahead and route our fuel line.

We're using this Starlight hose that's ultra light made by a

equip

and it attaches to this 45 micron stainless filter with a built in shut off. Now it attaches to the roll cage on the passenger side

and finally, we can run our rear pre

rent brake lines to the front of the car,

believe it or not short of a battery, we're finished out back. So let's move on to the front suspension starting with these lower control arms. These have got to be OEM pieces. Now you can use a steel pushing as long as there's no offset

and they got to be mounted in the stock location.

The spindles were using our metric

and they've been reamed to accept a larger ball joint.

Both the calipers and rotors are GM metrics and the rotors. Well, they've been red drilled to accept these larger studs in the five on five bolt pattern.

The upper control arms we're using are adjustable and not allow for easy change of Castor and Canberra.

Now, they're also available and also legal with a cross bar.

Well, now we're going to install our springs and weight jack plates up front. These springs have a five inch outer diameter with a 9.5 inch free height.

The plate sits on top of the spring like so

by the way, the rates of these springs are 650 on the inside, 750 on the outside to stabilize the car.

This jack bolt up here rests on top of that plate

and it allows you to make adjustments to change your ride height and spring rate.

Well, finally our shocks no rules on these. However, we're going with Bill Steins again,

seven inch stroke up front compared to nine inch in the rear.

Man. I can't believe how fast this thing's going together,

but it's time for us to take a break and when we get back, we'll go ahead and mount the front suspension, run the front brake lines and even get some of the body hung. So stick around.

Hey, welcome back to our modified build up. Now, I already started installing the front steering and we have to use a stock OEM steering box along with all the links and they have to mount in the original location.

However, the choice of the outer tie rod end and the adjustment tube is up to us as long as they're steel. So we went ahead and got ours from the speedway catalog.

Well, next we can connect the steering shaft from the box to this 2 to 1 steering quickener. It mounts right down here on the chassis and this is about as far as we can go. Right. Now. You see everything else mounts inside the enclosed driver's compartment.

Looks like my partner, Mike's got some heavy tin work ahead of him. Well, it's not as bad as you might think. The sheet metal is made of aluminum and comes in multiple colors. It's pre cut ready to install in the hardest part is finding the next piece in the pile.

The driver compartment not only keeps you clean, but it also keeps hot fluid and the fire off of you. And if you've ever done this,

then you'll know how important this is a collapsible steering column to keep the steering wheel out of your chest. Now, it's not mandatory, but you'd be a fool not to use one.

And if your front tires ever take a hit resulting in an uncontrollable steering wheel, this 15 inch disk aluminum one will keep your hands and wrists safe. Another optional safety item.

The last piece of hardware for today is the braking system for that. We're using this tri master cylinder pedal assembly. Now, it's a hanging reverse mount with individual masters for the front, the rear and the clutch. Now it has this balance bar which adjusts the brake bias from front to rear and that's how they kick the car sideways entering the corner

and it can be controlled in the driver compartment. With this bias adjuster.

I probably don't have to tell you this, but racing is never cheap. However, think about this, everything we've handled today, including all the body 10 only set us back about eight grand. Now, that's a whole race car minus the wheels, tires and drive train.

Try doing that with a drag racing budget. Now, next time we bring this thing back, we're going to build the status most competitive motor within the limits of the rules, of course. And well, then we'll be out slinging dirt and having a modified blast at the racetrack,

horsepower TV S hot parts. A look at the latest performance innovations from the automotive aftermarket.

This show is all about racing and here's a piece of safety equipment that's been making big news lately, especially in circle track racing. It's called the Hans Device and it restrains your head during an impact and moves with your body to prevent injury. It attaches to your helmet and your shoulder straps go over it. So it doesn't impair left to right movement. It's required in many sanctioning bodies and recommended for all types of racing.

The price 860 bucks.

Chances are you don't have

a dyno at home to check your car's performance but you may not need one

with this Pro RR performance meter from G

tech by powering up this little device, you can check your engine's horsepower, even measure ETS of the track and even handling G's. Then when you're done, you can just plug in back here and download that information to your car's computer.

It uses the same technology as the military's missile guidance system and mounts right on your windshield with this suction cup. It's a fun and effective way to measure your car's performance for only about 300 bucks. Well, that's it for hot parts. You know, we got a lot of this car put together and I learned quite a bit too, man. Me too. We'll see you next week for more horsepower.