Download Engine Analyzer Pro User`s Manual

(C) Performance Trends Inc 2009
Engine Analyzer Pro
Chapter 4 Examples
Figure 4.6 Mixed Data Graph Format Menu (displayed by clicking on MIXED in the
Graph Screen)
Click on this
button to enable
options on the left
side of this menu.
If this list is enabled
(not dimmed to gray),
choose the Torque
and HP vs RPM preprogrammed graph
pattern. If you do not
see these data types,
you are not doing
RPM data graphs.
See Figure 4.5.
Click on this button to enable
the specs on the right side of
this menu.
If these specs are
enabled (not dimmed to
gray), choose specs from
these combo boxed to
match those shown here.
If you do not see these
data types, you are not
doing RPM data graphs.
See Figure 4.5.
Now for the good part; lets install that carb and manifold. Get back to the Main Menu by clicking on Back in the menu bar (or
pressing <ESC>) at the graph screen (Figure 4.5), then clicking on Back (or pressing <ESC>) again at the tabular Test Results
screen (Figure 4.4).
When you return to the Main Menu, click on Intake System to obtain the Intake System menu as shown in Figure 4.7.
values in Figure 4.7 show specs for the new 400 2 BBL carburetor and manifold.
The
You will need to make 6 modifications to simulate installing this intake.
•
Click on the Total CFM Rating and type 400 over the current value of 255 CFM. Note: This particular Holley 500 2 BBL
flowed 400 CFM on a flow bench at 20.5" water (1.5 "Hg, mercury) . If it had not been flowed, we should have assumed it
flowed 500 CFM at 3 "Hg, the standard 2 barrel rating pressure. We would need to convert this to CFM at 1.5" Hg which is
what the program wants. The conversion is made by multiplying the 2 BBL CFM by .71, or in this case 500 x .71 = 355
CFM. See page 29. That would have been a more restrictive carb than the carb we actually installed. The same is true of
the Holley 350 2 BBL which should have only flowed 249 CFM but actually flowed 255 CFM.
•
Change the Manifold Type from Dual Plane-carb(s) to a Single Plane-carb(s) to identify the manifold being a lower rise
single plane design, where all cylinders feed from a single plenum. The Single Plane type (as opposed to the Tunnel Ramcarb(s)) indicates a manifold with lesser tuning effects due to a design somewhat compromised for good overall driveability,
smaller plenum and more bends in the runners.
•
Calculate a new runner size for the larger ports in the new manifold by clicking on the Clc button for Runner Dia @ Head.
See Section 2.9.3. At the Calc Avg Diameter calculation menu, chose No for Know Runner CCs?. Then enter the new
manifold's runner dimensions, which measure 2.0" high by 1.2" wide. The runners are primarily rectangular, so choose
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