Working on the AeroCav
 

Ok, I've been looking closely at the areas of my car that can be quickly modded at minimal cost and effort but I'm stick scratching my head about two parts.

http://thebest-prices.com/slideshow/...valier_Slv.jpg

Not my car, just an image of it.

Now down to business. On the doors is a molding piece, would its removal positively have an affect on reducting Cd, and helping airflow, or should it just stay in place. It seems to be nothing more than decoration.

Secondly, would it be better to block the hood grille (where the badge is) or block the bumper grille. I can't block the big hole infront of the drivers tire yet due to the air intake being in that location. It appears that I could block the grille at the badge, and block the outer two squares of the bumper grille.

If I went that route I could angle some coroplast to give me more of a pointed end than the current bumber design, on to the grille block and seal over the passenger hole to allow air to get directed that way. This would extend my front end almost 4 inches. I'll draw up some sketches of what I mean later and repost them here.

I think blocking the upper grill and the fog light? holes in the bumper would be best.

You could also probably block off some of the bottom bumper too, that thing is gigantic.

I'd leave the trim pieces on the door. They're hard to make look right honestly and they're 'bumpers' for the doors essentially. So when a kid (drunk friend, sloppy roommate, clueless girlfriend, etc) jumps in and out the car its harder to bang the door on something and leave a mark.

Indeed the hole in that bumper is huge, but its even bigger when you look at the two side holes that I can only imagine are for fog lights ( none I have found even fit). The one on the driver side has the opening for the air intake.

My goal is to cut that huge hole down to size and try to keep the angle of the bumper.

I would find a way to reroute the intake to come from the underhood area so you benefit from warmer air and then block off the big holes in front.

Agreed on starting with those upper openings as you decide how much of the total opening you can safely block.

As a rule, there's more advantage from blocking upper openings than an equivalent sized lower one.

As for the door bumper strips, their negative impact on aero would be really, really small (far too small to detect in testing, I'd guess). So unless you're going hardcore and truly don't care about appearance (nothing wrong with that!), I'd leave them on.

as mentioned above, block the upper grill, the angle of the resulting surface looks vavorable, you could also build small dams in front of the front and maybe rear tires,
based on comparisons of oem dams the ground clearance of the dam should be about 1/6 the tire height. oem dams often don't span the entire width of the tire but do follow the curve of the inner wheel well,

an undertray under the bumper and as far back as you can is also a good idea.

deleting mudflaps might also help if you can live without them... i this seemed to help on my previous car.

the most gains are to be had at the back though, but it'll be dificult to achieve

if the trunklid edge is rounded a small lip spoiler that basically straightens it might help, no fake wing spoiler though.

same thing goes for the underside of the rear bumper where an undertray might also have a good effect. fill in the large gaps or cover everything with a sheet.

i wouldn't worry about the moldings of the side (the front weel wells have messed up the flow already), or the fog lights (take a look at the new prius for example, they seem to have deliberately added a more blocky edge, so the fog lights might actually help aero!)

the last thing i can think off is next time you get new whipers is get some low profile flat blades... i'm quite happy with these and they do sit a little lower... whipers don't affect airflow very much, but it's still an easy mod to do

I can almost 99% guarantee that you can block that drivers' side air intake hole without harm. Somewhere on your air intake system, if your cavillac is like the one I used to have, the air is squeezed through a very small opening. Also, it appears that opening is open to the center grille some ways back (not sealed off completely if you block off the front.)

My escort's air intake snorkel has an opening that would be hard to squeeze a half dollar coin through.

I agree with what everyone else has said about the door bumper strips and the upper grill block being better.
Good luck with the car; Welcome to EM, and.....
You should definitely get some instrumentation going; either a Scangauge or MPGuino. Totally worth it and you will be able to see the (+ or -) results from your mods with higher resolution than the gas pump.