Front air dam, 4" or 5.5"?

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WillSquared

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So, I tore off the stock air dam a couple weeks ago since it was busted anyway. I see on LMC they offer a 4" and 5.5" version. Is this just personal preference or what? Mine is an 86 2wd C10 and had the 5.5" version on it I believe.
 

bucket

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From what I've seen on original trucks over the years, 2wd got the short one and 4x4 got the taller one. And only on 1/2 tons too, the heavier duty trucks didn't get one at all.
 

Green79Scottsdale

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While I can't comment on what came on what, keep in mind the air dam was an aerodynamic aid. It was utilized to re-direct air AROUND the truck, instead of allowing it to pass under the truck. Going around the truck is more aerodynamically efficient. Granted our trucks are literally shaped like a brick, but there are realistic things, such as air dams, we can do to improve the efficiency of them. Not sure if that helped, I just thought it needed to be put out there.
 

GTME94

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While I can't comment on what came on what, keep in mind the air dam was an aerodynamic aid. It was utilized to re-direct air AROUND the truck, instead of allowing it to pass under the truck. Going around the truck is more aerodynamically efficient. Granted our trucks are literally shaped like a brick, but there are realistic things, such as air dams, we can do to improve the efficiency of them. Not sure if that helped, I just thought it needed to be put out there.

That is exactly why I've thought about putting a 5.5" on mine. Even a fraction of a mpg would help.
 

WillSquared

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Oh I will definitely put another on. I just didn't want to put the 4" on and it look goofy or vice versa.


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Green79Scottsdale

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That is exactly why I've thought about putting a 5.5" on mine. Even a fraction of a mpg would help.

I have kicked around getting a C10 and doing a number of aero and mechanical enhancements to see what kind of MPG I could get out of our moving bricks.
 

Green79Scottsdale

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Oh I will definitely put another on. I just didn't want to put the 4" on and it look goofy or vice versa.

Buy the 5.5", and if it is too big cut it down to the size you want. Maybe you will end up with something in between...
 

bucket

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While I can't comment on what came on what, keep in mind the air dam was an aerodynamic aid. It was utilized to re-direct air AROUND the truck, instead of allowing it to pass under the truck. Going around the truck is more aerodynamically efficient. Granted our trucks are literally shaped like a brick, but there are realistic things, such as air dams, we can do to improve the efficiency of them. Not sure if that helped, I just thought it needed to be put out there.

My '84 didn't have an air dam on it when I got it. I drove it for a while like that and always kept track of my mileage (the real way too, not "I can go X amount on 40 bucks") and I ended up mounting an air dam because I had one and I figured it may help since I did a lot of freeway driving. More recently, I swapped my front bumper to the older style and I did not re-install the air dam because it never got me any more MPG at all. A wind tunnel may tell a different story, but my wallet says there was no difference.
 

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