Nitro Motor, Nostalgia Style
By Jim Burke
Running a modern dual spark plug, dual fuel pump, and
14-71 blown fuel motor is a scary proposition. The gentlemen who tune these
monsters should be anointed as geniuses. However, running a Nostalgia Fuel
Motor is not a scary deal by a long shot. It takes mostly common sense, a
little insight, and a lot of work to make this Nitro motor purr like a
First, I need to define the term Nostalgia Nitro Motor. I
am referring to a single spark plug, a single fuel pump, and a 6-71 blower.
This also includes running the motor at 85 to 90% Nitro. This combination
can be run without hurting a thing on a day in and day out basis. Though
this information is based on a Keith Black Billet aluminum headed 426 style
Hemi, in general it can be applied to most any motor.
The first two pieces of equipment you will need are a
Hydrometer and a Data Logger.
Get the best temperature corrected Hydrometer available. I
purchased a good one at Godman of Tennessee that had two hydrometers and an
Air Density gauge all packed into a wooden case. No, I didn't get anything
for that plug; it is just something that I have used and found that it works
as advertised. You absolutely have to be able to maintain the percentage
level of fuel that you run, across all the runs, no matter if it is hot or
This brings me to another point; Nitro is very temperature
sensitive. The Density of Nitro (what you are actually reading in the
Hydrometer) will vary significantly with the temperature and other factors
and it is of the utmost importance to be able to maintain a precise mixture.
What you thought was a 90% mixture may end up at 94% due to temperature
conditions. Believe me, the motor will know the difference Big Time.
The second item is a good data logger. There are many
brands in use; a couple I am familiar with are Race Pak and Autometer. There
is too much information required to tune these things to let it go to
chance. There will be certain tuning information that you will have to
acquire. An example is that a fuel motor has to be exhaust temperature
balanced at idle. I have used the Autometer Data Logger with good success.
Again, they don't pay me; it was a product that I used that worked as
advertised. If you are new to tuning a fuel motor, a data logger will quickly
become your closest friend.
The primary requirements are Engine RPM, Drive Shaft RPM,
eight Exhaust Gas Temperature Probes, your fuel pump pressure and flow, and the
blower boost. There will always be the need for more information, but these
are the minimum.
If there is enough interest, I will be glad to continue
Nostalgia Funny Car Reunion