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1966–70 Mopar B-body (Charger, Road Runner, GTX, Coronet) chassis

7 aftermarket chassis and subframes from 4 builders, compared with keeping and upgrading the original frame.

Art Morrison Enterprises, Roadster Shop, Schwartz Performance, Speedtech Performance

Aftermarket chassis

Prices checked Oct 2, 2026

Compare Builder & product Type Front Rear Price
Original chassis Keep it and upgrade itUnibody with welded-in front frame rails and a bolt-in K-member Factory SLA with longitudinal torsion bars, strut rods; recirculating-ball box Solid axle (8.75 / Dana 60) on leaf springs Kits from $5,348.94Cheapest kit in each area
Speedtech Performance 1968-1970 Mopar B-Body Torque Arm Rear Suspension Fits 1968-70 Mopar B-body Rear suspension n/a Torque arm $5,899.95 Listed price Source
Art Morrison Enterprises GT Sport Mopar K-Member Front subframe Bolt-on K-member, C6 Corvette-style forged knuckles, Sport C6 geometry n/a $9,560 AME builder 'Touring' package $9,560.00 (listed as 1966-72 Dodge Coronet/Super Bee, B & E… Source
Speedtech Performance 1968-1970 Mopar B-Body Extreme Subframe Fits 1968-70 Dodge Charger / Coronet / Super Bee, Plymouth GTX / Road Runner (B-body) Front subframe Forged spindles, Sweet rack, coilovers Not included $10,599.95 Base price Source
Speedtech Performance 1968-1970 Mopar B-Body Extreme Track Time Package Fits 1968-70 Dodge Charger / Coronet / Super Bee, Plymouth GTX / Road Runner (B-body) Suspension kit ExtReme front subframe, Sweet rack, coilovers Extreme torque arm $19,999.95 Listed price Source
Roadster Shop 1968-70 Charger FAST TRACK Fits 1968-70 Dodge Charger (B-body) Full frame RS Fast Track IFS, 58.75in track, C7-based forged knuckles, sealed hubs, RS SV by Fox coilovers, 1.25in splined sway bar Large-dia parallel 4-bar, Strange Ford 9in, S/S 31-spline axles; Fast Track IRS optional $22,495 From $22,495 (base) Source
Speedtech Performance 1968-1970 Mopar B-Body Extreme IRS Chassis Fits 1968-70 Dodge Charger / Coronet / Super Bee, Plymouth GTX / Road Runner (B-body) Full frame Forged spindles, Sweet rack, coilovers IRS, alum 9in, CV axles $33,902.96 Listed price Source
Schwartz Performance 1968-1970 B-Body, Coronet, Road Runner, Charger G-Machine Chassis Fits 1968-70 Mopar B-body (Charger, Coronet, Road Runner) Full frame Double A-arm, power rack, sway bar with spherical rod ends Moser full-floating 9" (58" hub-to-hub); IRS optional Quote only Source
Tick up to 4 to compare side by side.

Reading these prices

Starting prices aren't always comparable. Some include suspension, steering and brakes; some are a bare frame or front clip and the rest is extra. Check the Front and Rear columns and each product's notes before comparing totals. "Price on request" means the builder quotes each build. Confirm with the builder before you order, and send corrections through our contact page.

Upgrade the original chassis

How it's built
Unibody with welded-in front frame rails and a bolt-in K-member
Front suspension
SLA with longitudinal torsion bars, strut rods; recirculating-ball box
Rear suspension
Solid axle (8.75 / Dana 60) on leaf springs
Weak spots
A long, heavy unibody with unconnected rails, so it flexes under big-block torque. Soft torsion bars, rubber bushings and a slow box give heavy roll and poor feel.

Stiffening the body or frame? We list 6 kits for this car, such as frame rails, subframe connectors and braces, on its Chassis stiffening page.

Suspension and steering kits for the original chassis

AreaKitWhat it doesPrice
Front suspension Hotchkis TVS Total Vehicle Suspension System 80110 (66-69) Matched front and rear package that keeps the torsion bars and leafs $4,098.95 Hotchkis list Source
Front suspension QA1 Front Coilover System 52346-S400 (B/E body) Tubular K-member, power rack, coilovers; no cutting $5,524.95 QA1 list Source
Front suspension Reilly Motorsports (AlterKtion) AlterKtion Pro System, Street/Handling, 66-72 B-body Coilover K-member with valved power rack and 1.25in bar $5,995 Price seen on Reilly kit listing Source
Rear suspension Reilly Motorsports Street-Lynx 68-70 B-body RMS554 Triangulated 4-bar coilover rear replacing the leafs $2,495 Reilly list Source
Rear suspension Hotchkis Geometry Corrected Sport Leaf Springs 24366 1in-drop leafs with corrected geometry $699.99 Hotchkis list Source
Steering Firm Feel B-body Power Steering Box Rebuild Fast-ratio rebuilt box with firmer feel $550 $550-$595 by stage plus $250 core Source