Super Coupe Got Gapped
The lesson of the day was unrealistic expectations lead to crushing disappointment.
I bought my 1978 Dodge Super Coupe a little over two years ago out of California. A really solid, very nice driver quality ride, bone stock since it had to be smog tested every 2 years. You don’t know what a Super Coupe is? In the late 1970’s Mopar tried to capture the Duster 340 and Dodge Challenger buyer with Aspen and Volare sport coupes. Two door Mopar F-Bodies with spoilers, louvers, road wheels, hi-impact graphics and most times equipped with 318 or 360 V8 engines. Smokey and the Bandit was a huge success, it had a big impact within car culture thus Ford and Mopar wanted their own bandit car. For 1978 the Aspen and Volare got basically identical cars called Super Coupe. All with 360 engines and 727 TorqueFlite automatic transmissions as no manual option was available, HD suspensions, sway bars fore and aft. A bold look with fender flares, fat radials, black out hood treatment, colorful tape stripes. This was supposed to be the serious Mopar street machine…as serious as 1978 emissions regulations would let you get. Still it was faster than the Trans Am tested by Car & Driver that same year.
That doesn’t mean they were fast; malaise muscle cars were rarely fast fresh off the showroom floor. So, among my restomod plans for the Super Coupe were a few measures that would hopefully boost ¼ mile times. While the SC is still a work in progress the engine is basically a stock low compression piece. Topping the motor is a Holley Sniper EFI throttle body, with Sniper distributer, coil and CD box for better spark. All smog equipment is gone. The single exhaust with cat was swapped for a true dual exhaust without catalytic converters. The 727 TorqueFlite transmission was replaced with a Silver Sport A41 overdrive unit with 1st gear 3.06, 2nd gear 1.63 opposed to the 727’s 2.45 and 1.45 ratios. The peg-leg 3.23 rear axle got a fresh Sure Grip unit, that’s posi for you GM guys. Surely this must have been good enough for a snappier 1320 time. So, I decided to take the Super Coupe to Island Dragway in north western NJ to see what it could do. I was hoping for a mid-15 second time.
My first pass was simply leaving the transmission in drive, 16.22 seconds, ouch. The second and last pass I tried shifting myself for a 16.13, still lousy and much worse than I expected. During the second pass I was lined up and gapped by a 90’s Honda sub-compact hatch. During the ride home my wife could sense I was deflated, she tried to convince me we still had fun anyway. The Super Coupe got a lot of admiring thumbs up, malaise muscle doing what it does best. Later that evening I discovered that in 1979 Car Craft averaged 16.47 seconds with a stock Super Coupe, their best run was 16.35. When I explained to the wife that progress is measured in tenths of a second, I got a “who’s a good boy” with a pat on the head. Maybe it was a good day.
I believe at this point for the SC to match it’s show with go the 360 will need a performance rebuild. I don’t think a cam and head job will do it, am I right? Let me know with a comment below.
10/26/2020 11:07:24 am
John You have done a great job updating and enjoying the SC for the way it was meant to be.. Depending on your budget and available space, you may want to looking into doing a new HEMI swap ( 5.7 or larger) Like the GM LS Engines they can be found in used/wrecked Chargers, Trucks, Challengers, Magnums, and 300's. For the cost of a 360 Rebuild you can get one of these engines and they will be stronger, more durable, more reliable and more efficient for you since you drive your car more than the average Super Coupe owner. If you have the room, you can always keep the original engine on blocks to retain the value.
10/31/2020 10:27:42 am
Problem with a hemi swap is dont think it would fit that hemi is huge I had 2 switch brake booster just to put larger tappit covers on my 360 for the larger cam and roller rocker s hemi is good idea though
10/26/2020 12:11:40 pm
I would go with a Magnum Head conversion, step up the cam to something a few steps above especially on the exhaust and go with 3.91:1 gears. Side exit exhaust like the T/A and AAR would make big difference too.
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John is a GenX car enthusiast who grew up driving classic muscle cars. He enjoys the new modern muscle cars that can out perform the classics in every way. In the sportscar world his banners are Viper and Corvette. John has a guilty pleasure. The disco era street machine. Those unloved, underpowered cars festooned with scoops, spoilers and stripes.