Musclecars You Should Know: Chrysler Altered Wheelbase Drag Cars

mcyskmoparAWBBy the mid-1960s the musclecar era was starting to hit its stride, and drag strip bragging rights had developed into a proven marketing tactic. The NHRA’s Super Stock and A/Factory Experimental (A/FX) classes were among the most hotly contested battlegrounds in drag racing at the time, giving the factory teams high visibility to amateur racers and potential garden-variety buyers alike while also showcasing the latest hardware that the companies had in development.

The 1964 race season had been good to Chrysler. The new 426 Hemi motor had taken the motorsport world by storm, setting records in NASCAR and finding success in both of the aforementioned NHRA classes, breaking national records at the drag strip as well. But the other factory teams weren’t going to take this Mopar dominance lying down.


The 426 Hemi was a bonafide sensation right out of the gate, breaking records in both NASCAR and at the drag strip. But racing was big business by the mid-1960s, and competitors like Ford weren’t content to let Chrysler hog the limelight. When word got around that Ford was prepping a new SOHC 427 for use in the Mustang and Comet – cars that were significantlly smaller and lighter than the Coronet and Belvedere – Chrysler’s engineers knew they would need to do something pretty radical to stay ahead. Image: FCA

When word got out that Ford was planning to equip its smaller Mustang and Comet bodies with a potent single overhead cam, 427-cube motor for use in the Factory Experimental class for the 1965 season, the engineers at Chrysler knew they were going to have to take drastic measures if wanted to keep the larger Mopars ahead of those Fords.


Part of Chrysler’s strategy for the upcoming 1965 race season was to drop as much weight from the cars as possible – particularly at the nose. While the 1965 Race Hemi cylinder heads were essentially identical to their 1964 counterparts from a design and performance standpoint, they differed in that aluminum had replaced cast iron as the material of choice. The weight of each head dropped from 60 to 27 pounds from that change alone, resulting in a 66 pound weight reduction at the front of the car overall. Image: FCA

Jim Thornton, a Chrysler chassis engineer, was well aware that weight distribution was the key to getting the Hemi’s power to the ground out of the hole, especially when contending with the primitive tire technology that was available at the time. But the new power plant was simply a massive, heavy motor that added a significant amount of weight to the nose of the car in comparison to the engine it had supplanted for Chrysler’s racing program, hindering those weight transfer efforts.

To address this, Chrysler expanded its use of lightweight aluminum and fiberglass for body panels, replaced the door window glass with Plexiglass and the windshield with Lexan, while the engine team took some mass out of the 426 with a new set of aluminum cylinder heads and a magnesium cross-ram intake manifold. But the Coronet and Belvedere racers were still considered too nose heavy, so Thornton decided to go several steps further to distribute more of the car’s weight over the rear wheels.

The Original “Funny Cars”

While the Super Stock class rules yielded drag cars that shared the majority of their hardware with models and equipment that were available to the public, the A/FX class was significantly less restricted, allowing teams to develop packages that those companies never had any intention of offering through their dealerships.

Late in 1964, Thornton and the other engineers in Chrysler’s Race Group decided that the most effective way to distribute the car’s mass to the rear was to move the wheelbase as far forward as possible.


Back in the 1960s tire technology was still fairly primitive, and even full-bore race slicks had trouble putting the Hemi’s prodigious grunt to the pavement. Chrysler was among the most adventurous of the factory teams when it came to experiments with weight distribution – see the Hemi Under Glass for another great example of their out-of-the-box thinking. The company’s extreme measures with the altered wheelbase cars might not have gone over well with NHRA officials, but the oddball Mopars were undeniably fast and quickly gained a massive enthusiast following in match racing. Image: Mecum

To do so they brought the front wheels up by 10 inches and moved the rear axle forward by 15 inches while shortening the overall wheelbase length by 5.5 percent. The end result was a 110-inch wheelbase drag car that put 56% of the mass over the rear tires, weight distribution that was unheard of at the time.


Outfitted with a cross ram intake and dual four-barrel carbs, the altered wheelbase Mopars were dishing out low 10-second quarter mile times right out of the gate in the AHRA’s Factory Experimentals class they raced in, and would go even quicker once Chrysler green-lit the switch to Hilborn fuel injection during the season. As theorized, the standard wheelbase Mopars left to battle it out in the NHRA’s A/FX class struggled against the lighter Mustangs and Comets.

Five Dodge Coronets and five Plymouth Belvederes were allocated for the conversion, having their steel bodies acid dipped and then sent out to Amblewagon in Detroit for their altered wheelbase conversion before being delivered to factory team racers like Dick Landy, Ronnie Sox, and Al Eckstrand.

While there was no question that the altered wheelbase cars were significantly faster than their standard model counterparts, the Chrysler team hit a serious roadblock once NHRA got their first look at the new cars. Officials quickly drafted a new rule for 1965 that restricted wheelbase alterations to two percent versus stock for the A/FX class, effectively banning the altered wheelbase Mopars from the class they were designed to compete in.

But the cars’ wild appearance and impressive performance garnered massive publicity from the enthusiast press, and the cars quickly became a massive hit running match races in the popular and lucrative AHRA Factory Experimentals class around the country, where capacity crowds would turn up to see drivers like Roger Lindamood, Dave Strickler, and Bud Faubel pilot these “funny cars” to low ten second passes at nearly 140 mph. The cars got even faster once the teams switched over to Hilborn fuel injection systems mid-season in 1965.

The ten B-bodies earmarked for A/FX racing in the 1965 season had their bodies acid dipped and then were sent off to Amblewagon in Detroit for the altered wheelbase conversion. Along with a spartan interior that was devoid of creature comforts like air conditioning and a radio - along with a lack of passenger and rear seats - aluminum and fiberglass body panels replaced steel where ever possible. A Lexan windshield and Plexiglas side and rear windows replaced the glass normally used. Images: Mecum


Though the term would eventually be adopted by fiberglass bodied, tube-chassis dragsters in the years following, the altered wheelbase Mopars of the mid-1960s serve as the origin of the Funny Car term and remain some of the wildest factory-modified production cars built to date.

As privateer teams started to get in on the altered wheelbase act, many would add high riding straight axle front suspensions to the equation. Along with adding another layer of visual oddity to the the cars, this setup promoted weight transfer to the rear and was lighter than the conventional front suspension setup. Images: Hemmings

With the popularity of Chrysler’s factory-built altered wheelbase Coronets and Belvederes, private teams quickly began building funny cars of their own, and the altered wheelbase craze quickly spread not only to other Mopar models but other makes as well.

Today, altered wheelbase cars continue to flourish in nostalgia classes across the country. But with less than a dozen of the factory-build cars in existence, and each with a notable racing history, the value of the original Chrysler altered wheelbase cars has only risen over the decades since their debut, with examples like Lee Smith’s Haulin’ Hemi II Plymouth Belvedere commanding sums well over half a million dollars at recent auctions.


Extreme rarity coupled with racing pedigree and motorsport success means that the original factory-produced altered wheelbase Dodges and Plymouths are worth a hefty sum today. However, while more difficult to build that a standard wheelbase example, AWB clones like the one above have kept these cars reasonably accessible for those who want to experience what Factory Experimental race classes were like back in the day. Image: Hemmings

While the performance of the AWB cars would be eclipsed not long after their debut as more advanced technologies found their way into drag racing, their unusual design strategy and wild appearance remains iconic for a specific time and place in drag racing history, and the fact that they immediately ran afoul of NHRA guidelines immediately upon their debut feels strangely similar to a situation that a recently-unveiled Mopar now finds itself in. The more things change…

About the author

Bradley Iger

Lover of noisy cars, noisy music, and noisy bulldogs. Brad can often be found flogging something expensive along the twisting tarmac of the Angeles Forest.
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