FINESSE
A Modern Test of a Vintage Banks ProductWhen the diesel pickup craze began in the first part of the '80s, Gale Banks Engineering was one of the first to jump on the diesel performance bandwagon. GM and Ford debuted light truck diesels in '82 and '83 respectively, both of them were naturally aspirated. The 6.9L IDI Ford, a Navistar built diesel, delivered a modest-by-today's-standards 170 hp at 3300 rpm and 315 lbs-ft of torque at 1400 rpm.
They sold like hotcakes.
Well, the old adage goes, "There's no excuse for a naturally aspirated diesel." With his long background in gas engine turbocharging, Gale Banks was positioned to capitalize on the hidden power offered by turbocharging these naturally aspirated diesel pickups. The company was soon offering turbo kits to hungry buyers looking for more power and economy. Ford's marketing oversight gave Banks, and others, free reign in that market until 1993, when Ford's first factory turbo diesel debuted. Bank's first Ford kit debuted in '84 for the 6.9L and offered an 86 hp and 145 lbs-ft boost in power and torque over stock. Boost levels ran at 10-12 psi. The Banks equipped Ford offered bigblock V8 power and torque with six cylinder economy.
The first kits consisted of a non-wastegated turbo with a 3-inch mandrill bent exhaust system, an exhaust pyrometer and a cast alloy cold air intake system with a free-flowing oiled cotton gauze filter. In 1992, they replaced the original kit with the Sidewinder. The new design was an improvement based on nearly 10 years of diesel experience. Banks added the option of a wastegated turbo for much improved low speed performance. These wastegated Sidewinder kits are still in production for the old 6.9L and 7.3L IDI (Indirect Injected).
In November of 1987 a first generation Banks turbo system was installed on a nondescript white '86 Ford F-250 HD 4x4 6.9L diesel pickup that had been delivered in July of 1986. The truck was showing 6,725 miles.
To everyone’s surprise, this ’86 F-250HD 4x4 cranked out 194 hp on the University of Northwestern Ohio’s DynoJet chassis dyno. In its towing heyday, it could deliver about 11mpg on level ground at a GCWR of 17,000 pounds running 55-60 mph.
Fast forward to March of 2006. This same truck is still on the road with the same owner, yours truly, and now has 128,000 miles on its clock. At one time the truck was used exclusively to tow a variety of camp trailers up to 30 feet long, both 5th wheel and tag. It has also carried around two different overhead campers at various times. Now it's a farm truck that regularly tows grain trailers weighing up to 14 tons. Daily life also finds it performing a variety of other farm related tasks.
Recently, while dyno testing a modern turbo diesel at the University of Northwestern Ohio's new dyno lab for a story, we finished early and it was suggested that we throw the old '86 on the dyno for grins. It's been a long while since this truck has been matched against modern trucks, or even on a dyno.
The 1987 vintage Banks kit on an even older Ford 6.9L diesel. Neither have been rebuilt. The turbo mounts behind the housing, which contains a K&N free flow air filter. This version was non-wastegated and that was a good thing for a tow rig. In general, non-wastegated turbos have less backpressure and run lower EGTs under load than a wastegated unit. On the downside, they don’t have the low end boost and performance a wastegated turbo will offer. This kit was designed to deliver about 10psi of boost, but under certain circumstances, it has cranked out as much as 14psi. No intercooler was provided.
Hesitation. Any old man will hesitate when challenged to a physical competition with much younger men. Still, a dyno test is a good indicator of overall condition and since well maintained older trucks seldom have "heart attacks" under sudden exertion, unlike some older men, it was a "what-the-heck" moment. Pride is cheap and why not provide a few laughs for the crowd.
The numbers recorded knocked everyone's socks off and blunted the "old man" jokes before they were uttered. A three run averages yielded 194 peak hp at the rear wheels. Just minutes before, a stock '02 7.3L Powerstroke had turned in a 196 hp average. A recently tested '99 Powerstroke cranked out 203 stock hp on the same dyno. Encouraged by the dyno test, we ran some 0-60 tests with the old G-Tech performance meter and the truck can still crank out consistent 9.6 second runs.
If you use the average of a 30 percent drivetrain loss when comparing flywheel hp to rear wheel hp, then the 6.9L is still cranking out near the same 256 flywheel hp that Banks advertised back in the good ‘ol days. In years of towing, the truck consistently cranked out double digit mileage with loads of 8-12,000 pounds. Over its 19 years of operation, exactly one Banks part has failed... a small rubber boot that cost $5.00 to replace after about 15 years of service. Not bad for an old man, huh?