Before we continue with the construction of our ram air system, I first want to address a few issues.   The general thought with most things in life is that bigger is better.  With this thought, one might feel that  two 4 inch  inlets won't be big enough or, worse yet,  that the  3.5 by 2.5 area of the snout on each snorkel  won't flow enough air, but if we do the math we see there is plenty.   For those of you who think "math" belongs with the list of other 4 letter words that should not be said, I completely understand, please skip to the paragraph entitled Why it Works, but for those who want to see how it figures out, please read on. The math:       The facts for my calculations:              the opening area of  one inlet is 8.75 Square inches (3.5 * 2.5)              one square foot is = 144 square inches.              number of inlets =2              Speed 60 MPH or 1 Mile (5280 feet) Per Minute              motor size = 302              RPM @ 60 MPH approximately 3000. I got an average if 2560 so I rounded up       So if  we take 8.75 and divide it by 144 we get  .061 square feet.   Multiplying .061 times the distance traveled per minute, 5280 feet, we get a Cubic Feet per Minute flow rating of  320.83.  That figure is for one inlet but in this case we have 2 so when you multiply 320.83 * 2 we get 641.67 CFM.   The calculations for figuring the correct carb cfm for any motor at any given RPM are as follows. CID * RPM / 3456.   If we plug in the remaining  numbers,  302 * 3000 / 3456 = 262.15 CFM  draw from a 302 at 60 MPH and 3000 RPM.  To put it another way, the ram air setup is supplying 2.45 times the CFM required by our motor.  Now all of these calculations were done assuming that flow is reduced to the most restrictive point.  In reality, that is not the way it works. A short restrictive point will reduce flow, but not to a point equal to the most restrictive points area.  If you do all the same calculations for the two inlet tubes with a 4 inch diameter each (the least restrictive point in this system) we get a CFM of 921.53 or 3.5 times the CFM requirement.  Our actual flow rate would fall somewhere in between 921.53 CFM and 641.67 CFM.  There are too many variables like tube flow rate, air filter restrictions, and  air cleaner housing shape, to easily get it more accurate than a range of potential CFM. An average of the high and low is probably a fairly accurate approximation of the actual CFM flow of our system.  781.6 CFM at 60 MPH almost 3 times the motors CFM requirements. Why it Works:       As is addressed in my page "Efficiency -vs- Volume Increases", some of the power produced by a motor is used by the motor to run.  It takes horsepower to drive the water pump, fuel pump, and oil pump.  The same thing applies to drawing fuel and air into a motor.  With every intake stroke, horsepower produced by the motor  is used to draw fuel air mix into the motor.  By forcing the air in rather than drawing it in we are eliminating the use of that horsepower and reclaiming it at the flywheel.  Those are free horses with no penalty to fuel economy.   Another benefit is that the air forced in is cooler than the normal air under the hood. Cooler air is denser and provides more air in the cylinder with every intake stroke and improves the % burn (also addressed in "Efficiency -vs- Volume Increases") .  The last benefit is boost, up to 2 pounds of boost can be achieved at 90 + MPH.  Don't get me wrong,  Ram Air is no replacement for a supercharger or turbo charge, but still gives a small amount of boost that wasn't there before. The majority of the performance gains afforded by ram air come from large amounts of cool air entering the motor with no effort from the motor.

So here it is.  It fits well and the tubes will clear the parts of the motor.  It is now time to make it air tight, and plumb the air tubes into the front of our car.	We are now going to use plastic filler and fiberglass to seal all the holes on the air filter, strengthen the coffee can area, and smooth out the transition from round to rectangular.
Pictures and step-by-step instructions still to come.	Last modified 03/01/05

Tech Articles @ www.dazecars.com - Retro fitting modern seats in a classic Mustang - Retro fitting Mustang bucket seats in a 1962 Galaxie 500 in  place of the bench seat - Increasing horsepower   "Efficiency -vs- Volume Increases" - performing the UCA drop AKA Shelby Drop, or Arning drop on a classic Mustang, Cougar, or Falcon - Improve Mustang suspension by building a set of  Roller Spring Perches - Schematic for installing a 66 tipe amp gauge and a 1 wire alternator - Fabrication instructions for building a set of  homemade adjustable strut rods. - Putting a modern Mustang E-brake handle in a classic Mustang. - Understanding Bump-Steer and eliminating it or reducing it effects. - Suspension 101 Understanding the basic concepts of Mustang Suspension including most of the aftermarket kits and options. -  Ordering Information for DIY Roller Spring Perch kits, Steel Shelby Drop Templates as well as other performance low cost Mustang upgrade parts.

Disclaimer on Daze Tech Tips       I am not an expert in this field. I have performed these modifications myself with very good results. I am passing along restoration and performance tips for the purpose of education.  If you are concerned about reliability or safety issues, I do not recommend that you or any other individual perform these changes or attempt to modify your cars from stock configuration except under your own volition.  I do not assume nor accept any liability for the use of this information or how it is applied.

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