Airdam Reinforcement?

[josh817]

So yesterday I went out to eat with my family. Took my Z because I was going to go over to my girlfriends house afterwards. Well we pull up and I pulled up a little to car and the airdam slid over the parking bump. Ok so I backed up gingerly because it didn't bang or anything when it went over. Well there was a piece of rebar sticking out a 1/2" and it caught the airdam and tore it out.

Alright well I didn't like how it was mounted anyways and the airdam is fine it just tore out the holes the bolts went through. I saw on Hydridz a guy who had this idea:

http://fototime.com/BF9ED8490F9AC1C/standard.jpg

I want to do this but I'm not sure where to mount the struts to. Can't be fender or anything else like that.

Second problem. My rear spoiler is hollow. I have no idea how to mount it onto my z unless if I fill it with some sort of strong foam, otherwise the screws/whatever holds it will go through the very thin part of the spoiler and I risk cracking the fiberglass.

http://img214.imageshack.us/img214/6997/dhdfgvt9.jpg

^ Thin part I'm talking about

Those are my 2 problems. Next up is paint. Because I'm taking the airdam off anyways I might as well paint it. I don't know if I should buy cheap auto paint and just use my dads spray gun in a parking lot or what. I accidentally used the wrong cover paint on our SCCA BMW build. It was some cheap off brand paint, glossy black but damn it looks good for just one coat and cheap paint. As profane as it sounds I may just spray bomb the whole car. Not even the DIY Rustoleum, just spray it through like 50 cans with 3 coats. Being 17 years old, having an engine rebuild and then having to fix your car because the front end broke off is rough on the wallet. Besides if the spray paint sucks, then I can have some of my friends who make nifty drawing draw stuff on pieces of cardboard, cut them out to make stencils and make like an art car sort of thing. Stupid looking but doesn't take away from the fun. :] I try not to get to serious on the car otherwise I can forget about college and just use that money to make what... a perfect Z with no education? >_< No.

The roof of the BMW in gloss black spray paint, one coat, off brand paint:

http://i14.photobucket.com/albums/a333/josh817/BMW/HPIM1788.jpg

http://i14.photobucket.com/albums/a333/josh817/BMW/HPIM1790.jpg

http://i14.photobucket.com/albums/a333/josh817/BMW/HPIM1796.jpg

Tell me how you mounted your rear spoiler and then give me ideas for airdam reinforcements. Those would be very appreciated. :]

[EScanlon]

The Hybrid Z idea is sound, but going to the trouble of laying a 1/2" of fiberglass in order to drill and then Heli-Coil it is over-thought.

Why not just epoxy a bolt to the back of the dam and then bolt your reinforcing bar to the back of it?

As far as where to mount it to, I presume that the original poster at Hybrid had an idea in mind as to where he was going to post it. Rather than re-invent his idea, why not ask him? Not trying to brush you off, but he'd be someone who has done it. At a WAG, you could mount it to the bottom of the radiator support.

When you say your spoiler is hollow, do you mean that it DOES have a "floor" to it, and that the INTERIOR of it is hollow (that is, it's a triangle) , OR do you mean that it only has the outer two surfaces (and therefore two EDGES that touch the car) and nothing in between them?

If the first, cheapest answer I can think of is to get some 3M Double stick tape. Applied properly and allowed to bond and it will hold well to your hatch. Don't extend it past the hatch or you won't be able to open it ().

Double Stick Tape would also work on the second ONLY if there is enough of an edge to adhere to, otherwise you're looking at a spoiler that was due to be fiberglassed, or epoxied in place. There are other methods, but this is a quick reply.

Fifty Cans of El-Cheapo paint ain't gonna be cheap!!!

If you're planning on repainting the whole car, why not save some $ and have it done at MAACO or Earl Scheib? But for just the spoiler / air dam, you could probably get a couple of cans of paint that has been matched to your car from your local auto paint supplier.

But if you have access to a spray gun, you could get a quart of mixed paint, the reducer and stuff for much cheaper than 50 cans of spray cans....even the el-cheapo brand.

FWIW

E

[josh817]

Well they gave me instructions which say the basic things such as "measure, trim, mount" literally thats what it says with no actual instructions and it came with 8 long (but not long enough because if you look at the bottom of the hatch there is a piece of metal about an inch or 2 which sits between you and the actual hatch metal that the spoiler sits on) That lip that I showed in the picture is pretty much the only place to screw into and I don't want to brake the fiberglass.

This is what I mean by hollow:

http://img165.imageshack.us/img165/2016/fvcvnuw3.jpg

Also, the length of the rear spoiler extends over the edge of the hatch to cover the full width of the car. Its not a 3 piece though. I'm worried if I fiberglass it on, the end pieces may collect crap all up inside of the thing and do whatever dirty things it may do to the body of the car that is covered. I guess I could just use that spray foam stuff that expands as soon as you spray it (my dad used it to seal up outside water outlets on the house) and turns into yellow cauliflower looking stuff. But I really want this spoiler to be structurally steady, no breaking off or wiggling so I don't think double sided tape will do the trick... And I'm avoiding bondo.

How did everyone else mount theirs?

[Bread-Man280]

I know I am late to this, but...

If it were me, I would measure a piece of aluminum to fit inside the hollow portion of the spoiler. Bevel the edges if I had to, to make it fit inside flush with the hatch, but not force it and distort the fiberglass. Then I would find a good location on the hatch itself, somewhere thats easily accessible (like right behind the vinyl cover, inside). Next, I would match up the aluminum to the location I chose, and drill those babies. Now, I don't know what the size of the spoiler in question is, but I have pretty good idea so I would use maybe a 1/2" long bolt and cut it if needed. I would also match the holes up on top of the spoiler and drill that large enough to fit the bolt head into. I like the spray-foam idea. Fill it up, sand it down, and leave a nice hole bored thru the top. Epoxy on the aluminum. Epoxy works well for this if the aluminum is prepped right - I would sand it with something like 30grit. Slather that stuff all over the one side and put it in the spoiler, let it cure for a day or so. Clean up the excess pox. and bolt it on (after paint of course).

I have in mind making the piece removable so, it is up to you if you would rather fill in the holes on top or whatever, I would just smear some epoxy on the wall holes so the foam doesn't soak up water, maybe a little caulk around the hole in the hatch.

If anybody has done this and found it was a total waste of time, then please, tell me to shut up:stupid:. But it sounds good don't it?

[josh817]

No no no, you're misunderstanding what I'm saying.

Examine my photobucket album of my spoiler:

http://s14.photobucket.com/albums/a333/josh817/Fiberglass/

1: There are no drill holes, a very crude spoiler without any prep basically

2: See how it is hollow, and as you get further to the ends it gets hollower

3: See how thin that lip is, how do you mount that without it breaking

4: On the hatch behind that panel, see how there are 2 layers, how do you put bolts or screws in with that first layer of metal an inch in front of the main hatch?

Ok so now that I overcame the laziness and took pictures, what do you think?

As for the reinforcement of the airdam, I think I'm going to go over to Home Depot and buy 2 1/8" iron bars which are flat like a bracket. Use a torch to heat and shape them, fiberglass or epoxy it to the airdam and then put the other end onto the front bumper mounts which aren't used because with the MSA Type III airdam it has a bumper profile already molded in.

Or maybe I should sell this one and buy a BRE airdam because if I go into our club racing with the Z, MSA style will be point deduction since it wasn't used in 1972. Meh.

[FHPTOM]

Well after seeing those pics I would agree that it is hollow.

It seems that it was designed to be either bondo are fiberglassed in to make it look like it is one piece with the hatch.

Other than that I would think the install might look cheesy with a bunch on screws going thru it.

[ecp48]

The ones I've used in the past had a wooden block glued in on both sides, in the hollow. they line up with the rubber plugs on the inside of the hatch. Remove the plugs and drill through the hatch from the inside and insert the screw into the wood block. It would work for you as well. Just carve a couple of pine blocks and epoxy glue them to the inside of the spoiler.

[EScanlon]

When mounted on the hatch, does that rearmost edge butt up to the rear downward edge of the hatch?

If so, you might be able to mount it with double stick tape, the automotive type. See my edit of your picture.

Don't know what to tell you about the extension of the piece past the sides of the hatch. Was this piece produced for the Z or was it bought thinking it could be adapted?

FWIW

E

[Bread-Man280]

The bolts apply pressure to the aluminum not the fiberglass. the aluminum is attached to the foam in the spoiler and the fiberglass, so now the spoiler is semisolid with three sides to it instead of only two. you drop the bolts thru the top of the spoiler into the hatch area, only the spoiler has holes big enough to fit the bolt head thru not the aluminum, you will need to drill the holes yourself. hold a nut between the sheets of metal behind the cover and screw the bolt into the nut your holding there. the bolt does not protrude thru both sheets of metal. I know the area is tight but that is why you cut the bolt to a custom length.

If you still don't understand then give me the dimensions of it, maybe I think it is bigger than in the pictures.

[josh817]

Well because you guys posted suggestions, and there is no real how to for the reinforcement and the mounting of the spoiler, I will post my pictures of today.

Airdam:

1: Buy 1 1/2" X 1/8" flat iron

2: Measure the dimensions of the chassis so you have a piece that matches the hole you're bolting in, the distance between the chassis and the airdam, and how car of a piece you want to go over the airdam lip. This will give you a place to bend and drill your first hole to put a bolt through and into the chassis.

3: Bend the flat iron, this will be custom fit, there are no real angles you just make it work by bending and fitting to check. Its best to use a vice and place your marked spot on the edge of the vice, hammer/push close to the vice to, this will help you make a bend in the spot you want instead of higher up on the bar.

4: Fit your mount onto the chassis, don't drill the other hole just yet.

5: After the mount is in place, drill from the bottom of the fiberglass. As the drill bit comes through it will make a mark on your mount and you can drill the hole where the mark is. This will ensure that your holes line up.

6: Remount your bracket and you should be good to go. :]

I haven't made a spoiler one yet because the foam we sprayed is still drying. We did in fact get the foam you use on outside outlets, its called Great Stuff, $6 at Home Depot. We cut some would to squish into the foam. What we plan on doing is getting threaded inserts, drill and thread a hole in the wood, put the inserts in, and then put bolts through the hatch and into the inserts rather than using wood screws. Now there won't be any pressure on the fiberglass, just the wood held in by the foam. I plan to glass on the spoiler to so it looks clean but you have to be careful because the resin will melt foam and you don't want all your foam inside to melt. :]

Here are some pictures:

http://img174.imageshack.us/img174/9098/cimg0072ne8.jpg

http://img214.imageshack.us/img214/6231/cimg0080wx2.jpg

http://img214.imageshack.us/img214/8733/cimg0081wo0.jpg

The last one is my dad in one of his toys... We finally got around to clearing out the cockpit and removing the steering wheel. Before neither of us could fit because of our knees. It was the first time we had a grown person sit in it (baby step brother has sat in it). Long story short, he got all excited.

[toecutter]

Regarding that rear fin spoiler. Mine is also hollow, I just used a "slicon like" product called SIKAFLEX and a pplied it as per your first pic with the red line to show glue. Not sure if you get it in the US back it's worked fine for some years now. Oh and I brace the front bar as per the pics above also worked good.

Sulio

[josh817]

You have a really nice looking Z. :0!