1967 Rambler American Update - How To Build Your First Drag Car

'A straight-bodied, two-door sedan from 1967 for $2,000 that runs and drives? Sold. Our fantasy was to build a car and drive it solidly into the 10s because even factory cars are running 11s, and Car Craft hasn't had a really fast car since former Editor Matt King's Super Nova went deep into the 11s with a correction factor. We need to be faster.

With insurance cash in hand, we set out to buy the lightest, coolest car we could find. We apprehended a six-cylinder '67 Rambler American that we cobbled together in the May '06 issue and got running with gear from a V-8 Gremlin for a total of $3,500. It smoked its way down to San Diego for the Car Craft Anti Tour then lost oil pressure. We didn't care because we already had a plan.

Why 10s and not 9s? A quick glance at the NHRA rule book told us that 9s required a valid competition license and lots of expensive, SFI-approved goodies like a flexplate shield, a rollcage, and an unfashionable driving suit. We also found that if the car is full bodied and running anywhere between 10.00 and 10.99, you can get away with a rollbar instead of a 'cage. A 'cage requires a side bar on both the driver and the passenger sides of the car and a forward hoop that crosses between the roof line and the top of the front windshield. To us, the look of a 'cage draws the line between a street car and a race car. The 'cage is more complicated and expensive, and the rollbar is easier to hide and requires only one side bar that can be removable. According to the rules, a car with a rollbar cannot exceed 135 mph. So to give ourselves a little wiggle room, we settled on 130 mph as a top speed in the quarter-mile that should put us right around 10.50.

Gears, Mph, And Tire Height
After you've figured out how fast you want to go, you need to find the weight of the car and determine how much horsepower you'll need to accomplish your goal. The formula to estimate amount of horsepower for a terminal mph in the quarter-mile is: hp = (mph / 234)3 x weight. As an example, if your car weighs 3,000 pounds, you'll need about 500 hp to run 130 mph, and if your car weighs 4,000 pounds, you'll need about 685. This is simply a power-to-weight calculation, and experience has shown us it is a little conservative, much depends on the engines torque potential. There are a lot more factors involved in goin' fast, but this is a good place to start, and it shows why weighing less is better.

The next thing you need to do is find out where your engine will make peak horsepower and pick a rear gear that will put the engine at about 200 rpm above that number going through the traps in High gear. Here is the math: gear ratio = (rpm x tire diameter) / (mph x 336). This is closely tied to the size of the tire you are going to run, so before picking a rear gear ratio, find the largest tires that will fit under the rear. You should also note that an automatic transmission in High gear will exhibit about 5 percent slippage, so you will need to add that to equation.

If you've been following along, you know we pulled the six and showed you how to paint the engine compartment in your driveway. The 360 was stabbed using the same long-tube header combination from the January engine build and a V-8 crossmember from a wrecked '72 Gremlin.
If you've been following along, you know we pulled the six and showed you how to paint the
Instead of immediately frying the stock 904 TorqueFlite, we ordered a rebuilt one from TCI and a 3,000-rpm converter with antiballooning plates. We used the recommendation from TCI after we explained our cam size, combination, goals, and longing to eventually put nitrous on everything.
Instead of immediately frying the stock 904 TorqueFlite, we ordered a rebuilt one from TCI

We predicted the stock AMC Model 20 rearend would fail, and it did on the third run. It was also the cause of most of our slowness. The stock 2.71 ratio could only produce a 2.035 60-foot time, even with the 3,000-rpm converter. The next major upgrade is going to be axles and some gears from Moser.
We predicted the stock AMC Model 20 rearend would fail, and it did on the third run. It wa

The Reality
The Rambler weighs 2,771 pounds, so we ran the numbers and came up with 461 for an engine-horsepower number. Adding a 180-pound driver and and 10 gallons of fuel at 7 pounds per gallon, the race weight is more like 3,021, so the horsepower required is closer to 483. We plucked a 360 from a Jeep Grand Cherokee, and with some Edelbrock heads, a flat-tappet Lunati cam, and 10.5:1 compression, we made 480 hp at 6,000 rpm in the Jan. '06 issue, before we dropped it in the car. We solved the equation using 6,000 rpm for the ideal trap rpm knowing that with converter slippage the final rpm would be about 6,300. We plugged in the the 26-inch-tall tire, divided it by 130, and got a rear ratio of 3.57.

The Rambler's design restricted the tire size that will fit under the rear without either installing minitubs or relocating the springs. With the 15x7 rear rims, the tires are within 11/48 inch of the springs, and we had to trim the inner fender to get the tires to stop rubbing. The biggest tire we could get in there was a 235/60R15 that is only 26 inches tall. A larger tire, like a 275/60R15, has an overall diameter of 30 inches and would allow us to run a 4.10 ratio. Since gear ratios multiply torque, the higher numerical ratio would help the Rambler run a quicker 60-foot time. More tire allows more gear, both because the greater footprint would help traction and the increased height would still keep the trap rpm where we want it.

We have the weight and we have the horsepower, but for the first three runs, we used the stock 2.71 rear gear. The result was a baseline of 12.75 at 112 mph, which is exactly what Comp's Desktop Drag said it would be and about 2 seconds slower that the pure power-to-weight math wanted us to believe. The run pointed out that the small tire might be enough if we don't hit it too hard on the line, and we are definitely going to need a better gear ratio if we want to go fast. Knowing this, we are going to try a 3.55 gear with the small 235 tire before we return to the racetrack and see if we can go fast without cutting the car for minitubs.

PARTS LIST
DESCRIPTION	PN	PRICE
'67 Rambler American	N/A	$2,000.00
Engine total from Jan. '06	N/A	7,296.11
ADDITIONAL PARTS
TCI Torque Command 904	601100	1,009.00
TCI 10-inch StreetFighter	751600	432.88
Transmission dipstick	22160	74.02
Royal Purple transmission fluid, 5	N/A	8.95 / quart
Exhaust Labor	N/A	100.00
FlowMaster U-Fit dual kit	15936	183.39
Flex-a-fit radiator	52180R	899.95
Powermaster Ultratorque starter	9415	229.95
Stockton Wheels	15x5 and 15x7	440.16
M/T ET Street and VW front tires	235/60-15 and 165x15	411.90
PAINT AND BODY
Total from Dec. '06		645.40
TOTAL		$13,767.51*

*Low 12s on the motor in a reliable car that isn't a Chevy. Send rants to CarCraft@primedia.come.t.Corrected 12.36 at 115.36Uncorrected 12.75 at 112 mph

We were inspired by small-tire cars running in the 9s using nitrous and ignition timers instead of brutal wheels-up launches. We were also inspired when we found that by using 15x7-inch wheels with 5-inch backspacing, the 235/60R15 M/T ET Street radials tucked under the fender with only inner fender-lip modifications. Both wheels are from Stockton Wheel; the front skinnies are 15x5 with VW 165R-15 tires.
We were inspired by small-tire cars running in the 9s using nitrous and ignition timers in
We had Jeff's Smith's buddy Tim Moore weld in an exhaust bung for the Innovate O2 sensor. We've become addicted to the ease of tuning with the little handheld to get the car close to race ready. Then we only have to tweak the air/fuel ratio at the track.
We had Jeff's Smith's buddy Tim Moore weld in an exhaust bung for the Innovate O2 sensor.

For the baseline run, we used the stock fuel system, gas tank, and factory Jeep mechanical fuel pump. We haven't used the Innovate to tune the car, but we did use it as a safety measure in case the car was lean. At the top of the track, we were seeing 12.5:1, which is on the rich side. In theory, the best ratio is between 12.8 and 13.5 for best power. In the real world, you tune for mph.
For the baseline run, we used the stock fuel system, gas tank, and factory Jeep mechanical

Because this is a Rambler, there are no bolt-in applications for the radiator. We used the Flex-a-fit radiator with a 22-inch core that is 2731/44 inches wide and 1811/42 inches tall. The universal mounting brackets allowed us to mount it on the existing six-cylinder core support without welding in new supports. It also came with its own fan, and we added an electronic fan control so we could set the temp and forget it.
Because this is a Rambler, there are no bolt-in applications for the radiator. We used the
Notice we've avoided the standard fuel-cell-and-battery-in-the-trunk treatment, even though that was our first impulse. The NHRA rules say that if you move the battery to the trunk, you have to add a kill switch and a battery box; if you leave it alone, you don't have to do anything.
Notice we've avoided the standard fuel-cell-and-battery-in-the-trunk treatment, even thoug
The long-tube headers made the most power, and they also fit in the engine bay with the 360. We wanted the exhaust to go over the rear axle, so we used a Flowmaster 2.5-inch U-fit dual kit and had Wayne from Speedway Mufflers weld it together for us.
The long-tube headers made the most power, and they also fit in the engine bay with the 36

No way the stock starter would fit, so we again looked to the Jeepers and stole a ministarter idea from Powermaster. It uses the Hitachi silhouette design parameter, so it fits inside the headers if you remove them. The washers we used to set the lash on the ring gear turned out to be the same thickness as the transmission spacer, so we found one from another AMC engine and doubled them up. The starter makes 250 lb-ft of torque, which is likely more than the original six-cylinder engine did.
No way the stock starter would fit, so we again looked to the Jeepers and stole a ministar
We weighed the car and found that without the driver, it was 2,771 pounds. The heaviest corner was the driver's front, which will likely get worse with a CC guy behind the wheel, but the car is still very light. Once we get the rearend back together, we are going to find the center of gravity and work on launching the car.
We weighed the car and found that without the driver, it was 2,771 pounds. The heaviest co

SOURCES
Flex-A-Lite 8-00/-851-1610 www.flex-a-lite.com	TCI Automotive 151 Industrial Dr. Ashland MS 38603 662-224-8972 www.tciauto.com
Auto Meter 667 West 100 North Box 717 Ephraim UT 84627 435-283-4142	Powermaster Motorsports 2401 Dutch Valley Drive Knoxville TN 37918 423-688-5953
Loper's Service Center Phoenix AZ	Driveshaft Masters Harbor City CA driveshaftmasters.com
Kramer Automotive Specialties Herman PA 7-24/-285-5566 Kramerauto.Com	Speedway Muffler 951-371-6454
Holley Performance Products 1801 Russellville Rd. Bowling Green, KY 42101 KY 42101 270-782-2900 www.holley.com	B&C Auto Parts Gardena CA
Service Center Lomita CA	Galvin's AMC Rambler Parts Lodi CA ramblerparts.com