Double A-arm suspension

[volkdent]

Finally took the car for a short test drive today! Found this terribe metal-on-metal grinding sound from the front end, pulled the tires off, but couldn't find a thing!!! Torqued up the wheels and went to go for another run, but backing it out the noise just got louder. Pulled the tires off again, and this time I saw what was causing the problem, the inner edge of the rotor was rubbing on the bottom edge of the cup for the lower balljoint! I ground some of the the offending metal off, and on the second trip it was fine except at extreme angles, so I've got a little more to go, but should be fine. I'm aways from real testing, but I'll keep this thread up to date as things progress.

Jason

[DORIGTT]

Excellent

What're you pulling down now? 2.1g lateral?

[volkdent]

Originally Posted by DORIGTT

Excellent

What're you pulling down now? 2.1g lateral?

At least, on Big O tires...

I think the chassis will need a lot of stiffening first before I really start to push it. I think the whole body is pretty flexy, so I think I'll start with the chassis stiffeners from Eyeball Engineering(heavy though..), then start tying those to a roll cage. I just don't want to add too much weight. Even with just being lowered like I had it years ago there where cracks appearing in the body the door opening at the body line that runs down the side.

Ooops, that got me dreaming about a CF tub style VW chassis that you just bolt a body too...

Jason

[DORIGTT]

Have you considered making it a 'unibody' by stitch welding the pan and body together to make it a more unified & solid structure?

I read an article by a Spitfire racer who did it which resulted in remarkable increases in torsional rigidity.

[volkdent]

It might help some, but the trouble is the actual body panels aren't good at dealing with the loads. Welding a weak chassis you still have a weak chassis, with stress risers appearing in new and exiting areas!! I think a tubular chassis is the way to go, so I'll probably head down that route, I just don't like adding weight!

Jason

[helowrench]

you might look into adding the vert stiffening panels.
not just the frame rail stiffeners, look for the ones that go into the front of the footwells.

Thare are also some in the package area, but your 1.8T is there, so that is probably a no-go.

I have yet to find a comprehensive listing for all of the additional stiffeners that were added into the verts, but I am still looking.

Rob

[volkdent]

Thanks Rob, keep me posted!

Jason

[speedy]

hi jason , i saw the vid,impresive wheel spins, the engine sounds sweet
i am off to france for a month starting the 5th of jan so should be on here on a night keeping you up to date with my adventures and of course keeping track of your project seems it is now rolling
till then
jon

[volkdent]

Man, France for a month? That's a long time away from Helen, more job than you want maybe? I've got the perfect gift lined up for you guys, apparently it will have to wait until Feb. to be used. Thanks for the Xmas goodies, you know my weakness for chocolate is terrible!

Here's a little compilation I made up, if I keep on doing this I'm going to need a bigger harddrive! I didn't know making videos was so easy or I would have done it a long time ago!

Bad Dub Racing Inc.

[Panelfantastic]

Funny to look in the engine bay and not see anything!

[Bug@5speed(US)]

Very nice and congrats on getting it on the road..

Love the DM in the background.. Ah the memories of depeche mode from my days..
VR
Alex

[volkdent]

I took her down for an alignment yesterday, and to my delight and surprise, the specs on the front and rear suspension are almost perfect! They were so close to perfect that the alignment guy actually told me how impressed he was with how well built it was. I was really concerned that I'd be off quite a bit, I'm not a fabricator, so I thought the rear end might be way off, but I guess I did OK.

It's just a temporary thing so I can drive it around without worrying about wearing the tires poorly and it feeling twitchy. The alignment specs are for the car in a static position, but in April it will be going to www.huffakerengineering.com to have the geometry gone through during bump and droop to decide whether or not the rear will need to be rebuilt and what will really make this thing handle awesome.

Jason

[Pablo]

There is a company in the UK here producing something along the lines of you guys.

I seen it at our 1st Vdub get together last w/e. Have a look on there website Here

[Sandeep]

A very sweet unit indeed.

Sandeep

[volkdent]

Awesome to see someone else heading the A-arm route!!! I'm thinking that is an early prototype though, it's got some SERIOUS issues. For example, they've got the input shaft for the steering rack on the wrong side!!!

Joking aside, I do wonder about a few of things, the inner tie rods angle, the lack of adjustability beside the stock eccentric, they've not shown the parts to connect it to the steering column(which is a challenge itself!), the cups for the top balljoints are going to fill with water and debris and become a rust nightmare-especially in the UK, and the rear cross brace is made of flat plate, which isn't up for the loads of that position and isn't anywhere as strong as simple tubing, but weighs more.

I'm just excited some more development is being made in this direction, eventually we are all going to end up with a low weight, relatively low cost, high strength option to get away from trailing arm front ends!

Here's what's available for purchase on our side of the pond:

Eyeball-Engineering

Jason