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1970 Viper Powered Challenger Convertible

viper powered challenger by magnum force
Watch the construction of a 1970 Dodge Challenger
as Magnum Force takes a stock 318 Convertible and
merges it together with a 1997 Dodge Viper GTS to
create the epitome of today's

Pro Touring Mopar Muscle Car.

Episode 1 Season 9 - Ron and Mark take the Challenger for a spin.

(SEMA Has Eyes on a Hellbird Graveyard Carz)

Check out the build photos below and watch for the upcoming video right here!


 Magnum Force Challenger - Under construction photos

Viper Challenger.

Starting with a 1970 318 Convertible Challenger (which had a brief stint with a crate 360),  a wrecked 97 Viper GTS was happened upon.  Magnum Force will embark upon building a helluva drivable and highly enjoyable modern version of a good ole American Mopar muscle car.

Clearance becomes critical on day one with a big V10 and its fitment requirements so the first mandatory aspect of the builds foundation was a Magnum Force XRT tubular front suspension. Getting rid of the stock torsion bars, steering box, pitman arm, idler arm, centerlink, torsion bars, and huge k-member offered up a ton of space that previously just wasn't there. The front end ends up 150 lbs lighter and has vastly improved suspension geometry yielding some sweet driving characteristics. The Viper motor adapter mounts, now available from Magnum Force, are integrated into the new tubular k-member and additionally, welded to the frame.  A Magnum Force designed remote dual oil filter setup was needed for rack clearance and created accordingly.
Trying to locate the entire power plant in front of the firewall is a total no-no and results in a nose heavy, poor handling ride, so sliding the assembly rearward through the firewall rectified that scenario and just happens to locate the shifter in the ideal spot related to the driver. Appropriate bracing was critical in a ride like this, as convertibles are excessively flexible to start with, so a number of fixes were employed. Some hidden and some not. Underneath is a set of Magnum Force tubular subframe connectors, hidden inside the cowl is a chromoly infrastructure, and looking trick as hell in the engine compartment are a pair of forward struts tying the firewall into the upper coilover mounts and front frame rails. The firewall was modified and the transmission tunnel opened up as well to accommodate the six-speed viper transmission.
Though the temptation to go Viper on the rear suspension was clearly there, being that a 97 GTS was being parted out next to it, the desire to maintain off the line acceleration was still very much wanted, so rather than using the independent suspension from the Viper, or a heavier Dana rear end, the 8-3/4 rear end was powder coated, the springs relocated slightly and replaced with Magnum Force units, pinion snubber optimized, fat tires mounted, and launches ensued.

The internals of the motor were left reliably stock, with a custom set of stainless headers sporting 5 into 1 merge collectors fabricated by Ron being bolted on the outside. A custom air intake was fabricated as well, which ducts air in from above the radiator and just under the leading edge of the hood. A nitrous system ensures even quicker ET insurance.

Running big 17 inch Billet Specialties wheels on all four corners allowed the utilization of big brakes. 13 inch rotors with 6 piston calipers on the front and four pistons on the rear make it so this thing stops like a dream. The firewall, master cylinder, and entire pedal assembly were cut from the Viper & grafted into the 70 challenger resulting in a sweet layout that offers adjustable pedals as come stock on the Viper and easy integration with the Viper pedals, throttle cable, master cylinder, and slave cylinder. The Viper seats were extracted as well and re-covered along with the stock rear seat to match each other. A custom center console was created to house the stereo and other creature comforts.

Every nut, bolt, and bracket was either plated or powder coated in house and after all of the rust was repaired here at Magnum Force, paint chores were handled next door at Concours Auto Body, matching the paint job on the Magnum Force Viper with 1972 B5 blue stripes on black and matching b5 blue on the engines of both cars as well. Making for an incredible display cruising around the streets of Campbell California.

The end result is one incredible car to drive. This thing tracks, drives, stops, and goes so wonderfully it can easily be compared to a modern muscle car as you would currently purchase off the showroom floor.  A truly enjoyable ride through and through which cannot be overstated.