How to avoid scraping your lowered vehicle

[PMok]

I have found that even at stock height the BRZ has a fairly low ground clearance at the front end. I've managed to scrape the lower lip a few times already and now that I've re-wrapped it with black vinyl I want to take more care when driving into parking lots, driveways, spend bumps, etc. If your car is lowered then this is even more likely to be a problem.

The general advice given is to take such hazards at an angle. How much of an angle is required? Well the answer is it depends, on the severity of the dip/bump, and the amount of vertical ground clearance your car has. I will use my toy MRS as a visual demonstration, that way I can say no cars were harmed in the making of this tutorial.


In this first image we see the front of the MRS. As you can see the front end is fairly low, and there is considerable distance between the front of the bumper, and where the tires contact the ground. The notepad with the brown backing represents an elevation change -- it could be a speed bump, or a dip between the road and a driveway, etc. I'll just refer to it as a bump.


Now we approach the bump straight on. You can see that the front lip gets dangerously close to hitting the elevated surface. The problem is that your bumper may contact the surface before your front tires can roll to and contact it, which would help raise the car up as you roll up the bump.



Now let's see what happens when you approach at an angle instead.

Now as the front tire rolls up on the elevated surface, notice how much more clearance you have under the front lip. At this angle, the car will have no problem making it over the bump without scraping the front lip.



Note that as the front most corner of the car approaches the bump, it will still get pretty close to the ground. But the severity of the angle can help mitigate the potential of scraping by shortening as much as possible the distance between the front most part of your car and the point where your front tire will start to roll up on the elevated surface, in effect reducing the severity of the change in elevation your car has to traverse.

So the lower your car is, or the more severe the elevation change is, the more angle is required to safely clear it. There are usually practical limits to how much angling you can do, whether due to the width of a driveway, or other traffic, etc. and some bumps or dips will just be too much for you to clear.

That's where sometimes you will need the help of a few blocks of wood or some kind of mildly angled ramp to help you make it over. Put them right in front of the tires to help start lifting the front lip before it will contact the ground. Same concept if you have an issue of bottoming out in the middle of the car. If your car is really low and you care about not scraping, I suggest you carry a few pieces of 2x4 in the trunk wherever you go! Either that or know your limits and don't try to take on crazy bumps or dips at all. Here's an old diagram I prepared a while ago:


OK thanks for reading and happy driving.
If anyone else has tips or tricks please share!

[86_ZN6]

Good read!

My car is more than 2 inches lower than stock and i dont scrape.

Only once! Lol the first day i lowered the car. Haha

[zc06_kisstherain]

Angle is the key.
Nice demonstration!

Sent from my Galaxy Nexus using Tapatalk 2

[chutrain]

Approach and speed are so critical. But, it will be inevitable till that day when some part scrapes.

[civicdrivr]

Originally Posted by PMok

Took another sip of the potion hit the three-wheel motion

[Kevin@RAD]

I dropped it first, then learned how to drive. :P

Good thread, nonetheless!

[BigFatFlip]

Nice write-up @PMok. Just want to add that speed of approach/departure also plays a part. The slower you approach or back-out, the less likely you are to compress your suspension and bottom-out your front lip. Unfortunately, I had to learn that the hard way after backing out of my driveway in a hurry. Notice that all the scratches are at about 45 degrees, so I WAS doing the angled approach, but still managed to scratch (in both directions to boot!)

[PMok]

ouch! are you able to back out of your driveway without scraping if you go slow enough?

don't know if it bothers you enough to fix the underside of the bumper, but one thing you could do is get vinyl installed underneath the lip to cover up the scratches... cheaper than getting repainted. I got a local vinyl place to put some flat black vinyl on my lower lip.

[RRnold]

Nice example but there are plenty of youtube vids that show a real demonstration.

[ame="http://www.youtube.com/watch?v=SeCuhrOAKks"]Hard-Parked Aggressive G37s - YouTube[/ame]

[ZetaVI]

My parking lot at my house is an approximate hill w/ a worrisome angle that might be for the BRZ. I wish my parking was a complete flat surface. From my experience, angle def matters w/ gentle input on the throttle also to allow the tires adjust to change of elevation first. Go any faster the bottom lip will touch first and obviously won't end well.