Skid Plate Options - What to do?

[dnova89]

Yeah he got banned from here a while ago. I made an e30tech account for the sole purpose of buying his skid plate lol.

[bpmack16]

I have an oem one for sale

[ak-]

I have an oem one for sale

PM Robez

[Ferdinand]

I hit a rock on one of our winter rallies when we came over a blind crest to discover a huge rock lying in the middle of the road. On the narrow icy road there was no possibility of stopping in time or swerving to avoid the rock. It was just a question of whether I straddle it and whack the oil pan, or try to swerve and run over it with a wheel instead and risk tearing off the suspension?

As it was I hit the rock just off centre, taking it between the right front wheel and the oil pan, where the only damage was a bent steering tie rod, a smashed plastic chin piece, and a huge dent in the floor pan where the rock wedged itself dragging the car to a halt.



After that misadventure I decided it was time for a skid plate. I bought the OEM one, figuring that would be the simplest solution. Mistake.

Previously, at the car's stock ride height, there was plenty enough ground clearance. But the OEM rock guard hangs quite a bit below the car, significantly reducing the available ground clearance. Before fitting the skid plate the car never bottomed out. The rock we hit was a freak occurrence. Now, with the OEM rock guard, we were constantly smacking rocks.

You can see in this photo how far the thing hung below the car.



The OEM rock guard is very heavy, but the metal is relatively soft. With all the rock bashing we subjected it to, it was always twisted and bent out of shape. In particular, the long arms that connect up to the vehicle frame, see realOEM drawing, are way too soft and tend to bow out, so eventually the guard is pushed up until it contacts the oil pan anyway.

For my current car I bought ejknight's skid plate. It is waaaaaaaay better than the OEM system. It fits perfectly and works well. The skid plate is fine for normal abuse in tarmac events, and even survived this sort of treatment with only some paint scraped off.




You can see it hanging below the car in this next shot. With the usual 325is front lip in place you can't see the skid plate behind it. But we didn't want to risk scraping up the "is" lip, so we mounted the shorter 325i lip in its place for this event.



That said, we did eventually crack the oil pan on this red 325is on another gravel event, after banging over a nasty big rock. Ejknight's skid plate is beautifully designed, with lots of slots cut in it for cooling, and it works perfectly for normal abuse. However the slots weaken the plate. The pointy rock hit right on one of those tangs between slots and bent it up far enough to crack the oil pan.

If I was building a serious stage rally car, I would definitely consider using something more like the peerless design. A solid plate, with no slots in it, and especially with those two longitudinal ribs, is much stronger. And that tubular support bar is certainly going to be stronger than the flimsy arms on the OEM rock guard. I would make the plate wider though.

[robrez]

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Great insights, thanks for posting.

[michel smith]

How do you know if the driver behind you was writing down something else. If he would wrote down anything it would have been a waste of time. It is now the drivers word against yours. If you would of hit the car when you backed up. That's a cause for hit and run.

[Jparkr]

I hit a rock on one of our winter rallies when we came over a blind crest to discover a huge rock lying in the middle of the road. On the narrow icy road there was no possibility of stopping in time or swerving to avoid the rock. It was just a question of whether I straddle it and whack the oil pan, or try to swerve and run over it with a wheel instead and risk tearing off the suspension?

As it was I hit the rock just off centre, taking it between the right front wheel and the oil pan, where the only damage was a bent steering tie rod, a smashed plastic chin piece, and a huge dent in the floor pan where the rock wedged itself dragging the car to a halt.



After that misadventure I decided it was time for a skid plate. I bought the OEM one, figuring that would be the simplest solution. Mistake.

Previously, at the car's stock ride height, there was plenty enough ground clearance. But the OEM rock guard hangs quite a bit below the car, significantly reducing the available ground clearance. Before fitting the skid plate the car never bottomed out. The rock we hit was a freak occurrence. Now, with the OEM rock guard, we were constantly smacking rocks.

You can see in this photo how far the thing hung below the car.



The OEM rock guard is very heavy, but the metal is relatively soft. With all the rock bashing we subjected it to, it was always twisted and bent out of shape. In particular, the long arms that connect up to the vehicle frame, see realOEM drawing, are way too soft and tend to bow out, so eventually the guard is pushed up until it contacts the oil pan anyway.

For my current car I bought ejknight's skid plate. It is waaaaaaaay better than the OEM system. It fits perfectly and works well. The skid plate is fine for normal abuse in tarmac events, and even survived this sort of treatment with only some paint scraped off.




You can see it hanging below the car in this next shot. With the usual 325is front lip in place you can't see the skid plate behind it. But we didn't want to risk scraping up the "is" lip, so we mounted the shorter 325i lip in its place for this event.



That said, we did eventually crack the oil pan on this red 325is on another gravel event, after banging over a nasty big rock. Ejknight's skid plate is beautifully designed, with lots of slots cut in it for cooling, and it works perfectly for normal abuse. However the slots weaken the plate. The pointy rock hit right on one of those tangs between slots and bent it up far enough to crack the oil pan.

If I was building a serious stage rally car, I would definitely consider using something more like the peerless design. A solid plate, with no slots in it, and especially with those two longitudinal ribs, is much stronger. And that tubular support bar is certainly going to be stronger than the flimsy arms on the OEM rock guard. I would make the plate wider though.

Wow. sounds like something peerless would write...

Good info thanks for sharing.

[AndrewBird]

I see ejnight's skid plate as a plate made for low to moderate that is light weight and for people who want a bit more than nothing under the car. It looks great and seems to be well thought through. But IMO, 10ga steel is not thick enough, especially with all the holes he cuts in it. I tend to over build things though to prevent unexpected failures in extreme conditions.

Peerless's however seems pretty damn stout, though I agree with Ferdinand, I would have made it wider. His plate seems damn near rally proof and I think his description "Severe Duty" describes it well. I can see it being considered a bit heavy, but unless you are putting it on a full out race car, I think this is a moot point. There is probably a 10 max difference between the two plates.

I would think the ultimate decision would come down to whether or not you want to have to weld or if you want it to be more bolt-on as they are near the same price.

[3bvert]

if I hit something stout enough to destroy the ejeight I have on my vert, then I should have been driving my truck

[Ferdinand]

We really should have used the truck. It was an expensive mistake.

I'm still happy with Ejknight's plate. It was a worthwhile investment that I don't regret one bit. We pounded it back into shape with a sledgehammer and it's mounted again on the car now, after replacing the oil pan.

Having seen what rocks can do, it gives me peace of mind knowing the skid plate is there. We probably would have torn the entire crankshaft out of the engine otherwise. But if you're intending on doing hard-core rallying with your car on rocky roads, you might consider using something a little stronger.

[Ferdinand]

One other issue we had with the OEM rockguard hanging so low, was that we had to cut a coule of slots into the plastic splash shield that normally sits flush under the front of the engine, so that it could be bent down under the leading edge of the rock guard.

I stuffed the car into a snowbank once and had to be towed out. As we dragged the car backwards, the plastic undertray snagged and tore off leaving just the bare rock guard hanging down.

After that, whenever we drove in any deep snow, the rock guard would scoop snow up into the engine compartment. We discovered that on one of our winter rallies when it was -30 out and the engine suddenly started to overheat. What the heck?

I checked under the hood and found the entire engine compartment PACKED solid with snow. When the snow had jammed up most of the way up the backside of the radiator, the fan clutch eventually gave up, the fan stopped turning, more snow packed in there, and then no more airflow through the rad.

Good thing I discovered that when I did, because the hot engine and rad were trying to melt the snow, while the -30 ambient temperature was trying to turn everything back into a solid block of ice. If I hadn't scooped it all out before it froze solid, we wouldn' have been able to use the car again until spring.