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Old 05-16-2008, 04:15 PM   #23 (permalink)
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modifications-data-% change,or Cd change(nose-jobs)

Hello all. Randy_the_Hack asked about a breakdown of aero mods and their potential for savings.I've been pulling what I have together and since there is a lot of ground to cover,I'm going to post it as installments,in case the computer crashes and to respect the little time I have at the computer as of late.General note: all this data is dated now.All current production cars,pickups,vans,and SUVs should be employing some if not many aero refinements empirically proven over the last hundred years.Since carmaking is still ruled by the stylist it will be the last industry to evolve into the "form follows function" philosophy as in aircraft,ammunition,artillery,boats,canoe,kayak,pu mps,turbines,ordnance,ships,and submarines.The upshot is that ecomodders will have access to some of the existing fruit,which for their class of vehicle offers added mpg.As always,we need to be careful and mindful of the other motorists we share the road with.
I would like to have presented the material in tabular form although its beyond the scope of what I can do right now.(Nose-jobs):In 1937 Carl Breer used a "raked" front end to help his ecomoddered Chrysler Airflow to achieve Cd0.244.In 1938 the Jaray/Adler demonstrated a 15 % drag reduction with 100% grille-block.In 1962 L.W.Farington utilizes the 1976 VW "ideal" nose to help his 1956 Ford Thunderbird achieve 228-mph.In 1963 Walter Korff suggests that the optimal grille/radiator/nose/headlights/turn signals are good for a Cd0.07 improvement.In 1968 R.G.S.White allows an ideal nose to produce a 28% drag reduction.In 1974 CAR and DRIVER get 0.9mpg from airdam and 0.4 mpg from grille-block,1.4 mpg for combined,with "Crisis-Fighter-Pinto".In 1974 C and D get 1.2 mpg with 260ZG nose,and 0.2 mpg with plex headlight covers with "Crisis-Fighter-Z-Car.!975 VW Rabbit cuts Cd by 14% with Hucho's "ideal" nose.1978 Ford Capri gets a 6% drag reduction with wrap-around bumper with integral airdam and airfoil grille.1981 Pontiac Grand Prix flush headlights=1.5%,downward-sloping hood/fenders=1%,and softened hood leading edge = 1.5%.1982 Peugeot VERA cuts Cd by 0.015 with integral front airdam.1991 aero nose with headlight covers and lowered airdam add 1.526 mph to Phil Knox's CRX.1986 SAE Paper 860212: 100% grille-block cuts Cd by 0.003,airdam hurts bellypan car,airdam helps dirty-bottomed car.1986 SAE Paper 860211: 4.25-inch minimum radius needed for attached flow at leading edges,vertical or laid-back nose lowers Cd by 0.01.1986 SAE Paper 860216 (Subaru XT): front airdam cuts drag 6.9%,lowering nose by 10mm drops drag 1.7%.1997 Ford NASCAR with 1/4-inch lower front airdam beats Dale Earnhardt's Chevy.There are some other articles involving front mods however they are lumped into "kits" done for specific vehicles and no single-item breakdowns are given.I'll include this info in a future( Kits ) installment.Again,most of this info or similar will be found in Hucho's book.One member got it with inter-library loan for cost of postage.It's the Mother-lode!
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Last edited by aerohead; 06-12-2008 at 06:44 PM.. Reason: Additional material inadvertently missed with original post
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