Getting Started: About The New Chassis

Getting Started: About The New Chassis

The original chassis was probably salvageable, but by the time I added a new front and rear suspension and reworked the X member for transmission clearance, it would still be a 60-year-old chassis.

I did a lot of research on the aftermarket chassis’ available. Most of them use a derivative of the Mustang II front suspension and steering because they’re relatively easy to install and inexpensive. However, I think it is fair to say that the Mustang II was an underpowered, short wheelbase, piece-of-crap car that weighed about 2800 pounds and was not known for superior handling.

1974-1978 Mustang II General Statistics
Wheel Base	96.2 inches
Track, Front/Rear	55.6 / 55.8 inches
Width	70.2 inches
Height	50.3 inches
Length	175 inches
Curb Weight	Coupe - 2,620lbs Fastback - 2,699lbs Ghia - 2,866lbs Mach 1 - 2,778lbs
Engines	2.3L Four-Cylinder 85hp @ 5,000rpm 2.8L V-6 105hp @ 4,500rpm
Weight Dist. % Front/Rear	58 / 42

Any post-1934 potential street rod (not Willys) will probably have at least a 110-inch wheelbase and, with a modern drive train installed, weigh at least 3400 pounds with roughly the same nose-heavy weight distribution as the Mustang II. That’s approximately a 25% increase in weight.

After a good deal of research, I decided to buy a chassis from Chassis Tech in Redding, CA. Chassis Tech has a lengthy write up on suspension basics. Click here to read the article.

Chassis Tech makes complete chassis’ for 35 to 40 Fords and Chevys. They also make front clips for later model cars and pickups. Chassis Tech uses General Motors’ ‘G’ body (78-88 Regal, Grand Prix, Cutlass, Monte Carlo) upper and lower A arms, coil springs, GM 605 power steering box, sway bar, rotors, and calipers. Depending on options, ‘G’ body cars weighed approximately 3600 pounds and had a 112-inch wheelbase, the same as a 40 Ford.

The Chassis Tech product is built of 10-gauge steel and is fully boxed. The X member is made from 1" X 2" square tubing. The result is a very solid, heavy platform. The chassis came with motor mounts for a small block Chevy, an adjustable GM transmission mount (TH 350, 400, 4L60, 700R4) an 8 inch brake booster, brake pedal, Currie 9-inch Ford rear end, monoleaf springs, and disk brakes on all 4 wheels. The Currie rear end package included the Ford Explorer-type emergency brake set up (brake shoes inside the rotor).

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I ordered optional bolt-on body mounts that originally were riveted to the outside of the frame. The body mounts are now adjustable to level the body.

Ride height is adjustable at the rear via three mounting positions at the forward spring eye and at the front by changing the coil springs. GM ‘G’ Body front spring rates vary according to make, body style, engine, and accessories, so there are several options.

Chassis Tech’s product costs about 30-40% more than others that use the Mustang suspension, but I think it will be worth it.

The photos show the assembled chassis with a P-AYR plastic Chevy engine and 700 R4 transmission. The Chassis section of the site goes into more detail about assembly and the P-AYR engine/transmission.

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