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I'm thinking of making a homebrew skidplate for my 164's undercarriage, for winter protection and (hopefully) better aerodynamics. I think the two biggest challenges would be clearing the front downpipe and making sure the heat can evacuate. I wanted to know if anyone here has made one before and if so, what you made it from and if you have any pictures.
 

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I made one from an old aluminum highway sign I got from a salvage yard. I had it bent so it was pretty tight up against the oil pan with a small clearance. It was solid, but worked well when we were in Cheyenne, WY. No heat issues. When we moved to FL, I removed it because of the heat. You shouldn't have issues in MA with a solid one.
Cheyenne had these big dips in the city streets to drain water when they got rain, which was infrequently. I would bottom out in my 1991 164S that was 2 years old and only had 19,000 miles on it at the time.
 

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If I were doing that for protection from the elements and possible aero improvement, I might look into ABS plastic sheet, or similar.

Aluminum is cool, unless it gets loose for some reason and severs something important or hits the guy behind you. Less damage if plastic comes off.

Could be more difficult to work with if it needs to contour around exhaust and oil pan.
 

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I have the Alfa Ricambi steel straps designed pan guard on my S as it has been lowered and I pan the pan guard all the time on our crappy streets. The car came to me with stock suspension and a cracked pan. I need to put my spare pan guard on my L one of these days hopefully before I pan out the pan on it. I had it on my B and I took it off before i sold the car.

This one on ebay is what it looks like:
http://www.ebay.com/itm/Alfa-Romeo-164-Used-Original-OIL-PAN-GUARD-164-164L-164S-/161442777131?pt=Vintage_Car_Truck_Parts_Accessories&hash=item2596bd482b&vxp=mtr
 

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Discussion Starter #6
I have the Alfa Ricambi steel straps designed pan guard on my S as it has been lowered and I pan the pan guard all the time on our crappy streets.
Do those fit the LS? I thought they were 12V-only?


If I were doing that for protection from the elements and possible aero improvement, I might look into ABS plastic sheet, or similar.

Aluminum is cool, unless it gets loose for some reason and severs something important or hits the guy behind you. Less damage if plastic comes off.

Could be more difficult to work with if it needs to contour around exhaust and oil pan.
On another forum, someone suggested UHMW polyethylene sheet (the same stuff cutting boards are made of). Some off-roaders also use it - apparently it is tough, slick, and not terribly expensive.

Whatever I go far it's not going to be super beefy. I'm not going rallying after all (though I am toying with the idea of rallycross...). I'd like to keep salty debris out of the engine bay and maybe also have a tray for the car to "skate" on in deeper snow. Any MPG increases I can get from reducing undercarriage drag would be welcome too.
 

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When "skating" on snow, the front lifts, less weight on the tires=less traction in deep snow:)
 

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Ground clearance on these cars is normal, more than 5 inches which is plenty.

If you fit a skid plate made of metal then when it collapses against the sump it won't protect it.

Aluminum makes a hopeless skid plate, if you think you need one then two substantial steel bars are what will be needed. My 1978 SAAB 99 had two 2 in x 1/4 steel bars bolted under the transmission which hung below the engine on that car. I did hit those several times without incident.

If you want to provide some aero effect you need an underbody shield. Rigid plastic is best and, bonus, if you hit it hard enough to collapse it against the sump at least it has some give to it.

Seriously, for winter conditions you need no skid plates, the car performs very well in winter as you might expect for an Italian SAAB!
 

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My aluminum skid plate was rugged and very substantial, far better than a couple of steel straps. I bottomed it several times without it collapsing against the sump or anything. It protected the pan very well. It wasn't tin foil you know:)
 

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If you go plastic and you think you'll need to epoxy something to it, maybe avoid the polyethylene and polypropylene types. They are harder to bond to. Jb weld sells plastic bonder that will glue these materials, but I think it's a weaker bond. I keep that stuff on hand for plastic repairs on the alfa, as it seemed to work on the lower skirts.

I can understand the interest in this. All the late model cars use these lower engine covers. Seems to keep things a bit cleaner. I assume there's an aero benefit in the push for increased mpg, but aerodynamics isn't my forte.
 

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My aluminum skid plate was rugged and very substantial, far better than a couple of steel straps. I bottomed it several times without it collapsing against the sump or anything. It protected the pan very well. It wasn't tin foil you know:)
I think the aluminum sheet would have to approach 1/2 in thick to give the equivalent strength of 1/4 in steel bar. Flat plate aluminum is much weaker than steel plate or steel bar from an impact perspective. Steel bar would be my preferred material: better ground clearance, much better impact resistance, repair ability, better cooling and less risk of high centre pressure from deep snow. My guess is SAAB engineers deduced the same advantages. Oh, yes, and much cheaper to fabricate!

Unfortunately, strength testing these skid plates only works if you reach failure. Before that point you only know it was "strong enough".

As for aero advantages these come with cooling problems. Any skid plate that restricts airflow is going to heat things up, especially the sump. Those fins on the aluminum sump are there for a reason.

Finally, any skid plate increases probabilty of ground contact which is self defeating. For winter use the skid plate is likely to get you stuck for this reason. You want as much free clearance, no obstructions, as you can manage for winter driving. With fwd you do not want anything hanging below the car that might cause snow to wedge up the front of the car. That will get you stuck every time.
 

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I can't argue the getting hung up on snow thing. I've been there before with a buried front end in an 02 GTI and and 11 Lancer. There's just a limit to what you can power through. This only happened to me in work parking lots and on my last to be plowed street. Without those under body trays, I don't know how much better they would have done. When un-plowed snow is up to the bottom of the engine, it's usually time for me to stay indoors!

Regarding aero stuff, this may be interesting reading. Three part article. Starts with part 1 and then scroll to the articles on the bottom to find part 2, and the same from part 2 to 3.

AutoSpeed - Undertrays, Spoilers & Bonnet Vents, Part 1
 

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Do those fit the LS? I thought they were 12V-only? .
It will fit the 24v subframe, too. You have to drilll two M6 bolt holes in front and a M10 one in right rear side of subframe to mount it. M10 bolt is about 6" long.
 

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Aluminum Skidplate

This is the third one I have made for the 3 164s I have owned. This is on a 1994Q. As you can see it's not a single sheet but 1 1/2" wide 1/4" thick Aluminum Stock spaced 1.0" apart. Gives very good Sump protection with adequate road clearance.
 

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That looks awfully dangerous to me with such a bulking flat front. Hitting pavement at speed would rip that aluminum off in a spilt second, sending shrapnel all over.
 

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Skid Plate.

That looks awfully dangerous to me with such a bulking flat front. Hitting pavement at speed would rip that aluminum off in a spilt second, sending shrapnel all over.
But isn't that what a Skid Plate for ?? To absorb impact from road debris and act as a Sacrificial Lamb for your Sump ?? I have ran them for 7 years on all three of my 164s and never had an issue, anyway......... I am not posting to debate the merits of running a Skid Plate. A question was asked by the OP and I am just showing what is possible on these cars.

Howard.
 

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That flat front would catch on whatever you would be worried about, and would rip the thing right off.

While there may be roads somewhere which could be somewhat hazardous, in driving Alfas for over a million miles on all sorts of roads, including two trips across the country, the east coast, including NY city, and the mountains of the west, I've never hit the sump on anything tougher than grass and weeds. I don't see the point of having something like a big sump guard hanging down further limiting the ground clearance.
 

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Skid plates should not have any protrusion in the front, after all, "skidding" is like "skiing" or "tobogganing". Skid mean "to slide". Your design would dig in with calamitous results. And aluminum is really not the material to use. Is should be mild steel. Sorry to upset you!
 

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The 5/16 aluminum solid skid plate I made and installed on my 1st 164S had a sloping front leading edge and cleared the pan by about 1/2 inch, so as to give as much ground clearance as possible. It was secured on 4 corners by M10 bolts. I could very easily jack the car up on it. It was solid and secure. One can argue about the merits of a solid pan, but as far as being rugged, secure and functional, it was there!
 
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