Wishbone suspension bolt on kit

[MikeVW]

The mustang II has lower steer and I believe the steering arms are in front. The good part about the mustang setup is that you don't need to know much about steering design because it has been perfected in the setup. You just need to be good at fabricating and attaching the new suspension. I think most of the tunnel would be hacked away to make room for this proposed suspension.

Mike

[Shadowbug]

Originally Posted by MikeVW

The good part about the mustang setup is that you don't need to know much about steering design because it has been perfected in the setup.

this is only true if you are using the mustang II sock width, ride height and everything.

I'm using mustangII spindles on my locost (lotus 7 replica) and after plugging the MII dimensions into a suspension analyser I came to the conclusion that there is a lot of room for improvement. In an unequal length non paralell A-arm suspeension, you want as minimal movement of the roll center as possible, first of all the MII roll center was a little higher than I liked, and second it was all over the map in bump and roll.

I've dialed it in for my setup, so I get less than .05 inches of movement in 2" bump or a 3 degree roll, with the roll center at 1" below ground level. My rear suspension is a little looser woth .08" of movement and a roll center of 2" above ground level.

Once I'm finished this project, I'm going to build a new pan for my beetle with A-arm suspension front and rear, I'm fairly sure it "can " be done without cutting the pan (at least in the front) but it would be easier, stronger and lighter to cut out the old and build an all new sub structure.

If I were to market a kit to replace the stock front end with a A-arm unit I'd make it a weld in, so the owner will have to take some responsibility for it.

[volkdent]

Originally Posted by Shadowbug

this is only true if you are using the mustang II sock width, ride height and everything.

I'm using mustangII spindles on my locost (lotus 7 replica) and after plugging the MII dimensions into a suspension analyser I came to the conclusion that there is a lot of room for improvement. In an unequal length non paralell A-arm suspeension, you want as minimal movement of the roll center as possible, first of all the MII roll center was a little higher than I liked, and second it was all over the map in bump and roll.

I've dialed it in for my setup, so I get less than .05 inches of movement in 2" bump or a 3 degree roll, with the roll center at 1" below ground level. My rear suspension is a little looser woth .08" of movement and a roll center of 2" above ground level.

Once I'm finished this project, I'm going to build a new pan for my beetle with A-arm suspension front and rear, I'm fairly sure it "can " be done without cutting the pan (at least in the front) but it would be easier, stronger and lighter to cut out the old and build an all new sub structure.

If I were to market a kit to replace the stock front end with a A-arm unit I'd make it a weld in, so the owner will have to take some responsibility for it.

Thank you Shadowbug, this is the kind of language that is spoken when you are deciding to build a suspension system, so if you don't know what he's talking about, you need to learn before you suggest that making a suspension system is easy. Shadowbug knows more than I do about suspension geometry because he's worked with it on a program and in the real world, I have not even done that, but I've read a lot about it and paid someone who DOES know what they are talking about to design mine. Any time small changes are made it has a ripple effect on the whole suspension system, and small changes make big differences at the wheel.

S-Bug, when you get to that point, give me a shout, I have many of the pan dimensions laid out perfectly, and the idea of a rear A-arm system has been very intriguing to me too. BTW, you're link no longer works, I'd love to see what you've been up to.

Jason

[Shadowbug]

Rorty did your design didn't he?
He's well known in the Locost circles, he did a great design for and IRS for the locost. Mine was using a different donor, so design is quite different. Plus it looks as though his design is more of a cruiser, where mine is a little more of an aggressive autocross design.

When it comes time to do the beetle I'll definatly drop you a line, I'll probably use standard sheet metal for the pan halves, but center tunnel will be a triangulated tubular structure, so I can tie it directly to the front and rear pickup points.

as to my site, the link is fixed, but I haven't updated it for a while. Hopefully soon I'll get some pictures uploded of the locost build.

[Shadowbug]

I've been thinking...

to design a front suspension there are several "static" Measurements you need to start with.
ride height, roll center, track width and wheelbase
change any one of these and suspension design will not perform as it should.

so how do you design a universal "kit" that anyone can bolt onto the front end of their VW and expect it to perform, considering most will want to alter their ride height from stock, and there will be no set ride height that will make everyone happy.

I think I may have an idea that will allow at least some ride height options, without changing the suspension characteristics too much.
problem is, things start to get expensive.

how much would the average budget be for a kit like this?
a comparable Mustang II kit for a streetrod would be 3-4k

I personally wouldn't want to spend that much, how much would we be willing to spend?

also, Liability, insurance and safety approval costs money too, I'd hate to build a system, and get sued six months later by someone who couldn't bother to read instructions, or was abusing it beyond its designed tollerances.

I'd almost consider doing it, if it weren't for the leagal issues, or sell it as " for display purposes only," with no warranty expressed or implied.

and last issue, copy cats. a guy spends the time and money to design a system, and half a dozen others start building them with no R&D time, in direct competition.

I donno, there's a lot of desire out there for this sort of thing, but is there any money? only way to find out is to try.

Give me 6 months or so, I may have something scabbed together.

[volkdent]

Just a little update, I've not had any issues whatsoever with the front suspension. I think I need a little more castor, it doesn't want to self-correct, but it works just fine. No squeaks, no loose feeling, might be a little overdamped right now and may need a little more travel than what I have set up for the "in the weeds" look that I love.

Jason