how to help my matrix
 

What can I do to help my matrix get above 45MPG regularly? I can get around town 41-43 and on trips (steady state driving) I can break 45 some times. I feel that I am maxing out my driving options. I have a belly pan under the engine (past first axle).

I am thinking about mods that might help.
wheel well covers, what gain could I expect? how should I do them?
My matrix has a fairly flat back, would a tail or smaller mod help?

http://i835.photobucket.com/albums/z...r/GEDC0270.jpg
( Last winter, I took the hub caps off as they would not stay on)

I want any mod to be reversible, so attachments need to be hidden.

What are your ideas?

Start by inflating the tires to 45 PSI and blocking the upper grille, if you haven't already. That's an easy place to start.

They have been at 42-44 psi for over a year.
I had both a upper and lower grill block on over the winter, but as it warmed up I removed them so the fan would not run all the time. Should I still to the upper grill bock and let the fan run some?
http://i835.photobucket.com/albums/z...r/GEDC0284.jpg
Last winters set up.

Looks like there are a few things you can do, If you want a good list of ideas have a look at the garage section and see what mods others have done, the trip logs usually have some good info on what mod level cars are at and the MPG they got.

What will work best for you depends on what sort of trips you do. For example my normal commute involves short trips mostly so i concentrated on my cold idle which helped a lot. If you have lots of stop / starts due to lights look at weight reduction, if you are freeway driving mostly look at aeromods

either way a few MPG should not be too difficult with a few mods

Some ideas that i have tried that would work for you.
- side mirror delete, if you dont use them / if you can do head checks but check with your local laws
- mud flap delete, i think i can see a mud flap in one of those pics
- idle reduction both cold and warm idle (my car had seperate mechanisms for both) helps during P&G if you leave the car idleing rather than engine off, helps at lights, helps at start up
- power to manual steering, I have only just done this so im not yet sure if it is worth the annoyance of heavy handed steering
- weight reduction, what can you strip out of your boot that is just asthetic which nobody sees anyway. Can you take anything out of your engine bay, do you have AC you never use.

some other ideas i havn't tried
- look at plug up those round holes at for right/ left at the bottom of your front grill. Not sure exactly what they are for, if only one is for a air intake then block the other. See what you can do with them
- you can do more aero mods around your wheel wells although if you want your car to look normal this can be done but its difficult.
- engine block heater, heat up the engine with mains electricity before you leave in the morning. I have never tried this but plenty of threads on here about it and it might work well for you if your in snow areas
- you can do a full belly pan, will give you a bit extra but not much

Since you asked in your first post, Wheel well covers you can do with fiber glass which will give a good finished look but takes a bit of time. Otherwise you can do i out of coroplast and paint it the same colour as your car and try to make it so seam joins are hidden so it looks continuous as if there is no mod. I havn't done this yet, its on my to do list but there are plenty of threads about wheel well mods or others can suggest good ways to do this.
Yea a tail would work for you, someone in a thread mentioned anything more than a 12 degree change in angle will cause drag as air flow wont stay connected to the car. So you will have a large drag area behind your car. So a tail will help, very hard to make this look normal. You can also look at vortex generators which would go at the back on top of your car and intentionally disturb the air flow in a particular way so that it causes a smaller drag area. Plenty of threads on that one too.

Well good luck

thanks for the ideas!
comments, no mud flaps (icicle hanging down due to melted snow).
Mods it can look any way I want, I just do not want holes to patch if I take the mod off, so screws holding the bell pan on are on the under side where they will not be seen.

Weight reduction, I have done all that I am comfortable doing, I can remove some weight, but I have done some ABA testing (round trips to school and back on the same day, 90 miles each way) with 200+ pounds added and found that the weight makes very little difference (longer coast times offset by longer acceleration times).

Side mirror issue, I regularly have stuff in the back that blocks my view. I also feel that safety wins out over that mod.
The power steering to manual is an idea I might look into (I worked with steering systems for 18months). I wish my car had esteer (electric steering assist) where I worked they had data that showed a 1-2 mpg improvement from removing the power steering pump. The cost of an esteer system is the draw back, $300-600 added cost to make.

those round holes are where the fog lights would be if I had a non base model matrix. I been looking at them for some time as well, I can take out the plastic cover that you see in the picture, so I can mod them off the car.

I think a tail would be too big, but a Partial Kammback might work. I am looking for ideas on attachment that makes the hatch still workable. I think I could use the glass mounts for the lower part, but the upper has me stumped. Ideas please :)

I just might do the wheel well covers, I have both chloroplast and some galvanized sheet steel. which would be best? I can bend the sheet steel to make a lip to go into the wheel well (or at least several tabs). My issue with the wheel covers is that the back side of the car is inset from the tier (so my cover would need to stick out from the back side or have a bow out in order not to scrap the wheel. I can try to get some pics up tomorrow. Ideas?

on the Kammback, what is the best angle to use? base it off the level ground. Saand mentioned to keep it under 12 degrees transition from the roof to the Kammcack.

Other ideas?

...take a look at what Tango Charlie has done with his Pontiac Vibe (re-badged Matrix) for "workable" ideas as to how much & how well each mod has worked at improving his fuel economy.

good idea, but I am ahead of him in MPG

Here is the wheel currently:
http://i835.photobucket.com/albums/z...s/GEDC0135.jpg

My idea of a full wheel skirt:
http://i835.photobucket.com/albums/z...s/GEDC0143.jpg

the issue with a full one is that I would need to bow it out or else I need a 2-3" stand out on the back side:
http://i835.photobucket.com/albums/z...s/GEDC0139.jpg

Ideas please!

Here is how much I can cover by going strait across (magnets are on the edge of wheel well):
http://i835.photobucket.com/albums/z...s/GEDC0144.jpg

All ideas on how to build this would be helpful!

I can make a cardboard one first and I have chloroplast and galvanized steel as well.

bump for ideas