The Banks history is laden with trophies and awards for its accomplishments in gasoline performance. One example was the naturally aspirated Syclone.
That’s not to say that the original idea wasn’t to turbocharge the engine in the Syclone. On the contrary, Banks originally proposed things that would have made this vehicle a completely different animal as what was intended was for it to be based off of a full-sized Sierra truck using all-wheel drive for better traction and more evenly distributed power on the salt, and that it would be powered by a twin turboed big-block 502.
Those plans were dashed during a meeting about the endeavor with staff from Chevy saying that if there was going to be a performance full-sized truck it was going to be under their banner. GMC people said that they didn’t make all-wheel drive trucks and that none of the trucks they sold were turbocharged. The GM top brass made clear that they all had an idea of the truck’s image to be represented as a hopped-up stock truck that went to the salt. Banks was left the S-15 mini-truck powered by a naturally aspirated V-6.
The largest engine displacement available in an S-15 was a 4.3-liter. Since Banks was mandated to keep that engine, they decided to boar and stroke the engine to a 5.0-liter size, but they still needed extra power. Banks came up with a rather ingenious way to “supercharge” the air into the intake… naturally, and with no forced induction. Outside air was rammed in from two locations in the front of the truck and then passed through heat exchangers running circulated ice water from a tank in the bed of the truck and then into a specialized intake manifold. This changed the density of the intake’s air dramatically and increased the power throughout the entire run.
In the Summer of 1989, the Syclone truck went on to take five speed records, including an FIA International World Speed Record of 194 MPH. The following year the truck broke its own record with a 204 MPH two-way average and a top speed of 210 MPH! Not bad for dealing with something they didn’t originally want. Sometimes you just have to make do with what you have, but then again, isn’t that what hot rodding is all about?
The ironic ending to this story is that when GMC did come out with the Syclone for sale to the general public it ended up being all-wheel drive AND turbocharged. It turned out to be one of GM’s fastest production vehicles clocking 0 to 60 speeds in 4.7 seconds. But wait… didn’t GM not make all-wheel drive turbocharged trucks?