BREATHLESS PERFORMANCE PRODUCTS- Through Our
Endless Effort and Continuous Testing of Other Brands of Headers We Came Up With
Some Changes That We Felt Necessary. This Custom Header Has a Step Design, which starts at
1.3/4 and gets larger to 1.7/8 to Produce Increased Velocity Which in Turn
Produces Higher and flatter Torque Figures throughout the rpm range.
We also incorporated a velocity tip inside the collector to increase air
speed. Collectors are 3'' Instead of 2.1/2 We Fully Jet Coat
Our Headers Inside and Out. Dyno results have shown between 19 to 36 HP gains.
There were several tests. One test with headers without Cats,
then another without Cats and Corsa Indy exhaust on a 02
Next tests were done on Les's car, which is posted on
Z06vette.com, which it was just the header.
We have been using them in our Pro Mod and Pro Street
cars.
I will read you an article in Circle Track Mag Jan 2002
Exhaustive Choices By Jim McFarland.
Tuning Straight vs. Stepped Headers Primary Pipes
Note. Pressure excursions in header primary pipe may be
compared to simple harmonic motion of spring/weight system. Just as weight
oscillates up and down with amplitude and frequency related to specific weight
and spring constant, pressure waves transverse pipes in a similar fashion. Since
wave velocity is a function of pipe I.D a change in diameter affects the
amplitude and frequency of wave movement similar to change in spring/weight
values. Since peak torque9volumetric efficiency) is associated with specific
exhaust gas flow rates, the sizing of the primary pipe diameter affects the wave
speed9engine RPM0 at which these critical or "mean Flow" velocities. Stated
another way, the sizing of the primary pipe can be used as a tool to selectively
influence where in the rpm range torque boosts are placed or influenced. Step
headers are used to help increase the engine's effective torque range.
This is the reason we are the only header manufacture to
develop HP and Torque in the low to mid range and keep it all the way up on a
stock engine.
We will continue to show dyno results emphasizing the change
in HP and Torque in all rpm ranges. We are the only manufacture to use the step
design, Velocity tips inside the collector, 3'' collectors and a removable
collector for easy service work of the clutch or engine. |