Reverse induction
Backward Buick: A Reverse-Induction Nailhead V8
Posted on May 12, 2022 by MCG
This Buick Nailhead V8 with a reverse-flow induction system has been delighting and baffling the internet for several years now. Let’s take a closer look.
The homebuilt 1950s dragster shown here—and its remarkable engine—seem to exist today only in a handful of photos.These old images have made the rounds of social media and internet forums for several years now, generating tons of commentary but not much in the way of hard information. We thought it might be fun to dig around and see what we could find out.
Searching through old race programs, we discovered that the dragster was campaigned and driven by Edgar Stoffels Jr. of ETC Automotive in Chicago, Illinois. Obviously, that’s a Buick Nailhead V8 he has mounted between the frame rails, and a period entry list describes it as a 1957 model, which in its stock displacement is 364 cubic inches. (See our popular feature on the venerable Nailhead here.)
Now here is where things get interesting: We can see that the flow patterns through the cylinder heads have been reversed, so that now the intake ports are the exhaust ports and vice versa. Meanwhile, a GMC 6-71 blower driven directly from the crankshaft (check out our 6-71 history here) draws in air through a set of four two-barrel carburetors and pumps the mixture into the former exhaust ports. And where the intake manifold once was, there are now a set of eight individual zoomie-style exhaust headers. It’s a strange-looking setup, for sure.
So what was the purpose of this oddball modification? Exactly what the builder was thinking is not known to us, but we tend to agree, broadly, with the consensus theory among gawkers today: This was probably an attempt to overcome the Nailhead’s presumably limited breathing capacity. The Buick V8 was noted for its dinky exhaust valves (1.50 inches in 1957) and it was apparently thought that reversing the airflow and then pressurizing the intake ports would overcome the deficiency. Yes, there are some problems with this theory, and some mechanical hurdles to overcome, too: Among other things, a specially ground camshaft would be required.
Despite these obstacles, the reverse-flow Nailhead did indeed run, appearing at at NHRA’s Big Go, the 1958 Nationals at the Oklahoma State Fairgrounds in Oklahoma City, and at Cordova Dragway in Cordova, Illinois. Despite some tuning problems as described in the caption below, the ETC Automotive dragster was roughly competitive, racking up at least one class victory—against the Arfons Brothers’ fearsome Allison-powered Green Monster, no less.
Backward Buick: A Reverse-Induction Nailhead V8
Posted on May 12, 2022 by MCG
The homebuilt 1950s dragster shown here—and its remarkable engine—seem to exist today only in a handful of photos.These old images have made the rounds of social media and internet forums for several years now, generating tons of commentary but not much in the way of hard information. We thought it might be fun to dig around and see what we could find out.
Searching through old race programs, we discovered that the dragster was campaigned and driven by Edgar Stoffels Jr. of ETC Automotive in Chicago, Illinois. Obviously, that’s a Buick Nailhead V8 he has mounted between the frame rails, and a period entry list describes it as a 1957 model, which in its stock displacement is 364 cubic inches. (See our popular feature on the venerable Nailhead here.)
Now here is where things get interesting: We can see that the flow patterns through the cylinder heads have been reversed, so that now the intake ports are the exhaust ports and vice versa. Meanwhile, a GMC 6-71 blower driven directly from the crankshaft (check out our 6-71 history here) draws in air through a set of four two-barrel carburetors and pumps the mixture into the former exhaust ports. And where the intake manifold once was, there are now a set of eight individual zoomie-style exhaust headers. It’s a strange-looking setup, for sure.
So what was the purpose of this oddball modification? Exactly what the builder was thinking is not known to us, but we tend to agree, broadly, with the consensus theory among gawkers today: This was probably an attempt to overcome the Nailhead’s presumably limited breathing capacity. The Buick V8 was noted for its dinky exhaust valves (1.50 inches in 1957) and it was apparently thought that reversing the airflow and then pressurizing the intake ports would overcome the deficiency. Yes, there are some problems with this theory, and some mechanical hurdles to overcome, too: Among other things, a specially ground camshaft would be required.
Despite these obstacles, the reverse-flow Nailhead did indeed run, appearing at at NHRA’s Big Go, the 1958 Nationals at the Oklahoma State Fairgrounds in Oklahoma City, and at Cordova Dragway in Cordova, Illinois. Despite some tuning problems as described in the caption below, the ETC Automotive dragster was roughly competitive, racking up at least one class victory—against the Arfons Brothers’ fearsome Allison-powered Green Monster, no less.
