SKID PLATE EVO II

[Jordan]

hood mold is shaping up!

Looks great.

[max]

Come on, stop buttering up luke so you can get a fiberglass hood.... :lol:

[Jordan]

correction....kevlar.

[max]

correction....kevlar.

Come on, stop buttering up luke so you can get a kevlar hood.... :lol:

[Luke]

Spent the better part of the weekend working on the redesigned skid plate. It should hopefully prevent from ever having a cracked sump be the cause of a DNF again. I still need to weld additional wear strips on the underside and glue a rubber pad on where the aluminum contacts the chassis crossmember. The thing weighs a ton, but I keep telling myself that its low slung weight and its not like were short on power anyway! Overall I am quite please with how it turned out. John stopped by and we discussed the idea of rebuilding the original skid plate for use as a tarmac event sump gaurd, which I think is a good idea.

[Crazyswede]

Well i went down to where I have my non running saabs stored (a field behind a friends house) and we pulled the old rally car out of the hole it has been sitting in for a while. Everything is still solid but I have 2 flat tires. i am going to throw a new wiring harness in as well as a new transmission, and maybe a B turbo engine. Also need to do a hub swap. I looked at the skid plate and the support bars and they look very similiar to what you built. I will be getting a new digital camera soon and will get some shots of it. With any luck I'll be using this car for some Ice racing...or maybe I'll sell it and use the proceeds towards some other projects.

[SaabsBreakDown]

Well i went down to where I have my non running saabs stored (a field behind a friends house) and we pulled the old rally car out of the hole it has been sitting in for a while. Everything is still solid but I have 2 flat tires. i am going to throw a new wiring harness in as well as a new transmission, and maybe a B turbo engine. Also need to do a hub swap. I looked at the skid plate and the support bars and they look very similiar to what you built. I will be getting a new digital camera soon and will get some shots of it. With any luck I'll be using this car for some Ice racing...or maybe I'll sell it and use the proceeds towards some other projects.

How much do you want for it? Does it have a spec roll cage? Are you in NY?

Ugh. Always another saab for sale.. LOL

[Crazyswede]

I am in Vermont...not far from the New york border. the cage is not to spec and would take a lot of work to make it legal. It does have rally springs and rally valved bilsteins, brake proportioning valve, reinforced a arms, lightened steel hood, intercom etc. in its current condition I'd take $1200 for it as it sits. comes with an old set of rally tires on rims. will need to be towed home.

[SaabsBreakDown]

Very tempting, but I'm just going to build my own. Transporting that across the country would suck.

I'm buying another car on saturday so I might not get my cage in until January.. Spring Green '76 99.

That skidplate is beautiful. I think it does need some sort of slotted mounting assembly with only 2 bolts on the front, though.

[Crazyswede]

oh but it could be an adventurous road trip. You could leave the rally tires on and enjoy the vibrations that would cover your body from head to toe. The hockey puck motor mounts would add to that effect.

[james]

Luke,

that new skid plate design looks awfully close to the factory jig on my car. on that the frame is designed to be left on the car and the skid plate is removed from it via 4 bolts. when i got the car it was very hard to remove the plate as it had bent some and tensioned against the bolts. haven't thought of a better mounting system yet, although i haven't done anything with my rally car for a looong time. fired it up for the first time in a year the other day just to make sure it still would!

one thing, i see you are using 6061, as we all do. i have been thinking of other alloys as you found out that 6061 is not as strong as we hoped. 2024 alloy has a tensile strength of 70,000 psi, yield strength of 50,000 psi, brinell hardness of 120 and rockwell hardness of B75. it handily beats 6061 in tensile, yield, brinell and rockwell (60601: 45,000; 40,000; 95; B60). i have spoken to a friend who imports alloys and the 3 biggest drawbacks i see are that it can corrode (high copper content), it is not weldable and it is higher priced. but for a skid plate i think it would still work better. the higher strength alloys seem to be prohibitively priced until you price a gearbox or 2! so many alloys, so little time.

congratulations on your car, it looks very nice and i am sorry to have missed it at rny and brs.

james

edit: forgot to mention on the factory car the skidplate jig (frame and runners) is aluminium. that is one thing i think i will be changing.

[Luke]

Hey James!
Good to have you aboard! You'll have to give us an update of your car sometime. Ethan told me at STPR that you were thinking of running BRS, too bad you didnt make it out. Seth and I had a blast even though we put another hole in the gearbox.
The first skid plate we had was actually made of 6013 which is about 25% stronger than 6061 and very springy which helped it from getting too bent out of shape. I wanted to use 6013 again but I got a good deal on 6061 since its so common so I had to give it a try. Given how hard we beat on it I think it held up ok, but I think the support frame is what was lacking. I am sure we could use 1/2" plate and it would still get bent out of shape eventually without something backing it up. If this new one dosent hold up, I don't know what will. All this work with composites recently has got me thinking that a kevlar skid plate could be made super strong and way lighter. although $$$. That seems to be what all the works cars are using now.

[Crazyswede]

I am not familiar with the 2 series aluminum alloys but generaly for skid plates you want to go with something like a 6 or 7 series as they are a bit harder and dont gouge as easily. They are also weldable, and springy so you put a bend into them they get quite a bit of strength from the bend.

[Geoff]

edit: forgot to mention on the factory car the skidplate jig (frame and runners) is aluminium. that is one thing i think i will be changing.

That aluminum jig should be plenty strong, especially by comparison to a flat plate of aluminum. The flat plate does OK if its thick enough (yours is pretty thin) and any reinforcement with round or square stock will really stiffen it up. Plus it weighs much less. I'd just add another thick layer of aluminum under the one thats already there.

Besides it held up launching the car off a chunk of firewood and slamming my body into the harness crunching my junk!

[james]

luke- update? car's been sitting for more than 2 years, geoff was present the only time it was driven with verve and we tree stumped it. spent the roll cage money on a end-of-summer trip for my girl and i. damn, it's depressing. if you want any photos or info on the car just ask. i also have the homologation papers, with all the modifications the factory admitted to- some i never even knew of. forget sport&rally catalogue- this stuff is beyond that.

geoff- yes! my thought exactly on the plate itself. got to get 1/2" down there. maybe a 7 series aerospace alloy.

if my girlfriends and my street cars stopped braking maybe i could work on the rally effort...

james