Modding the Geo Metro

[arcosine]

If 185/80R13 fit without rubbing then 185/65R15 should fit without rubbing. I may have to bash the inner fender wall.

[MetroMPG]

Originally Posted by Baltothewolf

Uhg please don't cut the springs. The ride quality will be absolutely terrible.

^ Not my experience.

In fact, I've tried both dedicated lowering springs and chopped springs on a Metro, and the chopped springs were better (in terms of ride comfort/stiffness compromise).

I actually went in and removed MORE from my Metro springs after the first cut.

Of course it's a question of how much is too much, and that's pretty subjective.

[Ecky]

I believe the way the math works out for cut springs vs softer springs, you lose total travel either way (that's just the nature of lowering) but the cut springs will be effectively "stiffer", because their spring rate increases. If you're looking to just lower, you should cut a slightly softer spring. If increased stiffness is desirable too, cutting the existing springs is fine.

[arcosine]

Yes, if the spring has 5 coils and one is cut off, then the stiffness is only 20% more, should be hardly noticeable, unless its on the bump stop.

[me and my metro]

When I lowered my last Metro I removed the bump stops all together. I only hit the limit once and it was with the car loaded and in my driveway. I recommend leaving a little bump stop. I lowered the rear of my Saturn L 200 sedan by cutting one coil off the spring. I cut the bump stop in half, the rear came down about an inch and a half. The ride is fine I just need to run it through the alignment shop the rear toe was off before and this made it worse. There is a lot of adjustment in this car, I may need the adjustable lower arms to get the camber correct.

[Ecky]

I put stiffer, shorter springs in my car a while back, to keep ride height the same. I just removed several hundred pounds from my car and I plan to just take another half coil or so off the springs. I still have the old softer springs if the ride proves too harsh.

[MetroMPG]

I haven't hit the bump stops yet. But I also took a lot of weight out of the car. (Interior is currently pretty much stripped.)

[arcosine]

Lowering a car lowers the roll center further than it lowers the CG, therefore the car will have more body roll, which is just the opposite effect intended. Stiffer springs are used to compensate.

https://motoiq.com/the-ultimate-guid...e-roll-center/

This visually shows what happens to the roll moment on an over lowered car. For cars that are extremely low, like some race and drift cars, the roll center must be corrected for this reason. Check out the difference in roll center height vs CG height in lowered and non lowered examples."]his visually shows what happens to the roll moment on an over lowered car. For cars that are extremely low, like some race and drift cars, the roll center must be corrected for this reason. Check out the difference in roll center height vs CG height in lowered and non lowered examples.

The often-overlooked disadvantage to lowering is that roll center drops more radically than the center of gravity on most cars. Although lowering the center of gravity and increasing the track width are the two most effective ways to reduce weight transfer, over lowering increases the roll couple and dynamic weight transfer. This can cancel any steady state weight transfer advantage that lowering the center of gravity can have. The huge roll couple created by over-lowering will require an overly stiff suspension to control body movement. And when your suspension is too stiff it won’t absorb road irregularities effectively, which will make it harder to keep the tires in contact with the ground nnd you can’t drive fast if your tires aren’t on the ground. This is called tire shock by us engineers.

[freebeard]

https://www.musclecardiy.com/perform...-single-a-arm/

[JohnAh]

I have not been experimenting with aerodynamics, but think that a full belly pan can do more than lowering and/or a front dam. If the intention of a front dam is to improve fuel economy you don't want to get a low pressure under the car, since that will cause turbulence. I THINK the best is modifications that gives a minimum stir-up of the air below the car, and that is HIGH ride height, a smooth belly and a front splitter.

The single most beneficial aero-mod seems to be a boat tail extension, but that's probably the most extreme mod you can think of. I would definitely look into at least a part kamm-back or boat tail extension, a front splitter and a flat belly before I go bezerk with all those tiny things such as wheel covers, removing windshielt wipers, grill block etc.