Custom Chassis Work

It's winter, and I'm bored, so that means I am thinking of all the things that I will do to my car in the future because I'm not driving it now. That said, I've been doing a little looking into what I can do to "make it a sports car".
This winter while I'm redoing the interior I am planning of patching up some areas on the floor. Then I thought about just replacing the floor pans. Then I started thinking about just having a new chassis built for it next winter during down time. The question from me is "What do I have built for the speedster?" I've put all this work into the rear and practically everything else is new as well so what can I have done that would allow using the parts I currently have but also to enhance handling and stability.

Kelly and Cory,
I ran across these guys in your area, have either of you heard of them?
http://www.metricautohaus.com/metricautohausprojects.html

I cut and pasted this from another thread because I think it got lost. Anyway, I was looking for input on the subject. What are the thoughts on having a custom chassis built? What is entailed in putting a speedster body on anything other than a VW chassis? (Hello Cory). As stated above, I'd like something really solid. I am looking to creat a sports car that handles considerably better than what I have. What should I be looking at in getting a custom chassis built?

Thanks in advance for your input - Mickey

Mickey, they're the people who've been doing the work on Paul Rich's car.
I don't know what his opinion of them is.
I can presonally recommend AutoFab Race Cars, in Laurel, Maryland. Hands down, the best shop I'm aware of in my area. I'll get the details to you if you want. They will make whatever changes you want to your car, professionally and with a great deal of concern for how you intend to drive it afterward.
They speak metric.

Mickey,

Years ago there was a chassis made for the Speedster my MetalCrafters. Maybe you can find out more about it. That design would be a place to start if you want a totally different chassis.

I'll email Paul and see what he has to say about them.
Cory, any info you can get me is appreciated.

I'm really clueless on this one. I don't know what's realistic or overkill or what. I've seen chassis' similar to Cory's (minus the hoops) that go for around $1500. I've also seen "upgraded" versions of the standard shortened VW pan that go for $700-$900. I may want to do some sort of roll ball and side bars for safety and stability purposes but how do you design such a thing being that all the bodies are slightly different. I don't want overkill, I'm not goin racin'. I just want something I know I can beat the piss out of and not worry about. I'd also like it if it could be built with a lower tunnel (more like the original) to "clean up" the interior. Plus it would be the perfect time to relocate the ebrake.
I did a search here and saw a few guys that have/are building their own chassis. Is there anyone who has completed one and can shed some light? I know Cory's car is one, but even he has said that it was built to go "fast in a straight line" (it does do that) and is considering suspension mods.
And how much of a PITA is it to reattach the body? Things like wiring, fuel line ect..., is it pretty straight forward?

If you label your wires carefully, it shouldn't be a giant pain to re-wire it. You'll discover -- especially if you have ADHD and OCD like me -- that you'll start cleaning up every end, every connector and every spade or loop you come across; that's a years-long endeavor.
Make sure, if you do decide to do this, that the labels include little funky alpha-numerics, like B+ or -3A, which should be stamped into the castings of whatever they plug into. Having a wiring diagram as you begin dismantling it will also help. You can pretty easily make one with a Xerox of one of those factory blueprints and several sheets of vellum; make overlays for yourself specific to your car, and make the wires with appropriately colered fine-point pen. Green for green, black and silver for black and white, and so on.
I'd say you should maybe talk the chassis over with somebody like Henry or Carey, too; registration won't be a problem, but you'll still have potential legal problems if it doesn't bear a number and somebody gets a wild hair. Alternatively, maybe Henry has some adaptations to your design you could get welded in for rigidity; you could avoid re-inventing your car.
Also, pursuant to the original question, your horn will never work again. I've got an extra chrome horn button you can have, 'cuz you're going to eventually mount a button on the dash. I'll even drill the dash for you, thereby saving you approximately three days' worth of lumps on your forehead from banging it into the steering wheel in frustration.
You want I should start working up possible chassis designs? Heh, heh ...

"Also, pursuant to the original question, your horn will never work again."

Nah, that's not true at all. You can use the earlier Beetle and Porsche set-up with wire brushes contacting the steering shaft, or the later wire up through the shaft and the braided connector wire bridging the coupler and just use the stock Beetle wiring diagrams to connect the horns up properly.

If you use a vintage wheel like one of the old VDM or other offerings, you can even activate the horn using the ring and use the center button to flash your lights, activate the high beams or sound a separate high-way horn.

Lots of European cars were fitted with city and country horns.

Just wires, hot and ground with something electrical in the middle and a switch somewhere between.

Anyone care to weigh in on the "overkill" aspect of a custom chassis? I'm trying to decide how far to go in the repair of the current floor boards VS welding new ones in VS the custom chassis. Is there any real big benefit to a tube chassis? I feel like I could put in new floor boards and tighten things up and have a pretty solid car. I just don't know how much better it would/could be if I have something built.
Anyone have any experience with both? Are there gonna be any cars at Carlisle that I can compare.


Cory,
Don't get the pens out quite yet. BTW my wife was amazed at your drawings of my decklid you did when we were trying to figure out the attachments.

All the tube chassis cars I've seen are really rigid, with the narrow point over the shift linkage being eliminated. It seems like that's the wasp-waist of the VW chassis-box-tube, CMC-style designs that still incorporate a VW pan. The car's metalwork seems to twist there just a little. Adding metal plates between the box tubing and the torsion tube to connect them will probably suffice for you.
I'll vote no on a new chassis for the Lil' Dink. it'd be overkill for you to go through the trouble, since your car is built and solid enough.
I'll vote yes on gussets and extra reinforcement along with new, German pans, but you don't need to re-work the whole thing. It's in great mechanical shape -- IMHO.

(Lil' Dink -- that little delinquent needs a name, after all.)

I agree with Cory. Since you have a subframe, the body itself is probably plenty rigid. The areas where a tube frame would help are at the rear where Cory described, and again at the front. The Beck fram is welded to the beam as far out as possible, making it a bit more rigid up there. There are reinforcements available that you can bolt or weld on a Beetle frame to get the same result.

Cool. I may need some guidance with the reinforcement stuff. I did put those bolt on arms up front that attach the frame head to the beam. They seem to help.
Lane, Cory, Anyone, I guess I need some advice on what and where to do the reinforcing. Are we talking about making sure the body is better supported by the subframe or the subframe itself is better, or more rigid (reinforced)?

Neither. The subframe - and with it, the body - is what it is, and that's almost certainly adequate. What you want for better handling is for the front and rear suspensions to be more rigidly held to the frame/subframe/body assembly. Cory described where the engine/transaxle/rear suspension is held only to the tunnel as a "wasp waist", and that is an apt description. That narrow tunnel can twist, allowing the suspension to move relative to the body without the springs actually doing anything. The same thing happens at the front. The normal beam-to-pan interface is only about a foot wide, but the beam is much wider. Again, the beam can move relative to the body, allowing for roll, even without the wheels moving relative to each other. In such a scenario the chassis is an active piece of the suspension - not good, because it's not easily controlled.

I'll use the Beck frame as an example because I'm most familiar with it, but the same things hold true for other such frames. Go to Carey's website and find the picture of the frame, or look at that electric Speedster x-ray view on the thread about "Cool concept Speedsters". You can see that the main frame rails are welded to the beam as far apart as possible, limiting any movement of the beam relative to the frame. The same is true at the rear, where the torsion spring tube is welded to the frame out at the ends. John Steele has a suspension/frame reinforcement package available that you might want to look at as a way to beef up the connections between frame and suspensions on a pan-based car.

Rigidity could be further improved by making the frame more "3-dimensional" with uprights and a under-dash hoop that included braces down to the frame platform, and something similar in the rear. Cory has done something like this on the Hoopty, and you can really feel it. Unfortunately this would be difficult for the manufacturers to do, as the interior surfaces are glassed into the body prior to bonding to the frame. To do something like I described in a kit would take a design similar to the Factory Five Cobra, where the body is just a shell, and the space frame contains the interior, whose flat surfaces are aluminum panels. It would be nice, but it would also be much more expensive.

Mickey, it would be an interesting study in retrograde engineering if you asked Henry directly what he did in the transition phase between your car and the next generation.
Whole chassis designs rarely grow in giant leaps; there had to be experiments, and he'd almost certainly be forthcoming about them.
The best space-frame/monococque construction I could manage is what I gave Jimmy when we first got started, and my car will never, ever corner well as a result. He built cars to go really fast in a straight line -- it's what I wanted back then.
You will need suspension pieces tied in with the integrity of the Beetle body's welded edges, and not a whole lot more. The Beetle derived its integrity from being tied into the pans at the perimeter of the shape, and the roundness of the rear apron, the complex curves at the nose and decklid and the tube frames of all their members; the oval frame horns, the rounded or scalloped hinges, etc.
If you get your car in the air and look under it, you'll know where the narrow or unsupported points are; it'll almost be intuitive. Where there's metal hanging out in space, support it in three dimensions, and tie what you make upward into something else horizontally. Simple shapes work best; pyramids, triangles and pure arches hold up very well over time.
Here's the narrow point. The two tabs from the crossmember to the torsion tube could have been welded anywhere along the torsion's length. The metal there is tremendously thick, and there's nothing in there that's sensitive to heat -- except grease. The torsion rod lives for about an inch of the tube's diameter at the geometric center of the tube -- plenty of room to weld without changing the metalurgical properties of the torsion rod.
Naturally, having the rods out, the suspension therefore disconnected and the grease washed out would be better and less dicey, but hell. It's only going to make a small fire.
Kidding aside, here's what I decided on:

So if I

In Cory's photo you can see a threaded hole right above the end of the torsion tube in the casting that goes up to support the top of the shock.

My CMC has a connection to the subframe there. I assumed all pan/subframe Speedsters had this. It seems like this would accomplish about the same thing as Cory's welded in pieces. I don't know why Cory's car doesn't have this connection since I think it started life as a CMC.

To gain any advantage from the under-dash hoop, you'd need diagonal braces going forward from it to the front beam. No sure how to do that without a lot of cutting on the body. My guess is that the braces you've already put up front are adequate for the kind of driving that you will be doing. Do you have a picture of them?

Like Cory said - different objectives (top end speed, comfort, handling) all conflict with each other in chassis design. In college, a friend had a British Morgan 4 (TR4 powered) which had an Ash wood rail frame that flexed as your cornered --- it really held the montains roads along I-81 in southern VA. Never lifted a wheel like a stiff go cart suspension might. it wasn't comfortable on interstates though. I've always thought the CMC subframe was totally over built - a a few hundred pound could be reduced there. I had a '59 AH Bugeyed Sprite which quickly lifted a wheel - but with its short wheel base, light weight and limited power (950 cc) was a blast to drive. Many VW T1s have been modified in the rear to use 944 and 911 parts. Weak (handling) area is most likely the front end and the torsion twist bars - that's major fabrication to change that out and keep a VW pan. With so little weight up front it might even be a waste of effort/$ (upgrading to disc brakes and a sway bar are best bang for $).

Michael,
Do you mean like the ones in the picture below? I disconnected the ones on my car for two reasons. One, the driver side was disconnected as the bolt snapped. Maybe welding something is a bit stronger? And two because I now have my upper shock mounted directly to the subframe. Is that what could be causing the problem, that the shock is no longer connected to the original arm?

Lane,
I figured as much in regard to the dash support frame. I will post a pic of what I've put up there when I get the car on the lift, hopefully in the next day or so.

So, it seems like it's an "all or nothing" scenario. Either you deal with the pan and do a few little support mods, or you just go balls out with a tube chassis. It looks like it's more beneficial to maximize what I've got now. I did a search on this and it looks like Ron Klink has done some pretty good work in this area.

Mickey,

Yes.

Michael,
I'm not the sharpest knife in the drawer. Did you mean "Yes" to the one in the picture, or yes to all the other stuff too, or both?

Just yes to the first question about the picture.

You may not be the sharpest knife but you probably have more experience with sharp knives than the rest of us.

I'm hoping to get my car over the my buddies garage this week and get it up on the lift to look over the rear suspension and clean a few things up on the pan.

I ran across this pic on IM's website. It's exactly what I was looking to do to support the vertical post behind the door jam in an attempt to add structural support. Is this something that can be done with the body on? I figure I can cut out a hole large enough to weld the piece to the subframe post and then just weld it to the frame at the base of the door. I have no problems filling in the cut outs once the welding is done, it's just patching fiberglass. My question is, being a very amatuer welder, is this something that can be done without too much hassle?

Sure, but it'll be a genuine pain in the ass to enter/exit and for how much gain?.

Just to throw fuel on the fire, give a gander to to this website for some chassis mods:
http://www.eyeball-engineering.net/

Mickey-

If I'm not mistaken, every 911 powered Intermeccanica has that brace.

I had a pair added to my frame during the build process, as I am absolutely fanatical about stiffness. The brace (as configured) makes no difference whatsoever in the difficulty of entrance or egress, adds quite a bit of stiffness to one of the weakest areas on an open car... and looks way-too-cool beside.

I'd heartily recommend it.

Very Cool site Dave! I see a future transaction with them. I really like those pan stiffners.

Stan,
You mentioned you had this done during the build. I'm a little confused as to how the body could be put on before hand. I mean either way there has to be some cutting done in that area, right? I'm not worried about the getting in and out thing. I'm only 5'10" and I have my seat far enough forward that it shouldn't be in the way. Plus I get to choose the angle so I can keep it reasonable. I just hate that weak point and want to sure it up a bit.
I'm trying to get as much stuff done while I have the interior out. I figure as long as I'm sanding, grinding, and welding I may as well do as much as possible.

I agree Micky- if you've got the interior out, now's the time. If you do it, and you follow the basic geometry of what Intermeccanica does, you'll love it.

Thanks Stan.
I hate to be a PITA but if possible could you post a couple pics of your set up? I see the one in your file of the passenger side but I was hoping to see how and where the top support goes in at the door jam. Maybe some close ups and/or measurements? It'd really be helpful. I'll even engrave your name on one of the supports for "props". ;)

Here is some more fuel for the chassis guys:

http://www.desert-craft.com/offroad.html

http://www.red9design.co.uk/wishbones.htm

http://www.classic-centrum.de/Kaefer_Lenkung_1.htm

David,
Thanks for the links! I am seriously considering a set of those pan stiffners on the Eyeball site, though they're out of stock.

I had hoped to get to do some speedster work today but with the freezing rain we had I wasn't up for hypothermia. So tomorrow the plan is the fill any and all holes, gaps and seams in the floors to get it prepped for a good coat of POR-15. I'm also going to cut out the body section and weld in the subframe supports the Stan has on his car. I hope to get all that done by the end of the week. Next week I can start on cutting new carpet pieces and getting them ready for the upholstery guy to sew the edging on when he does my seats.

On the seat topic - What do you guys do for seat-track brackets? Up until now I just had my seat tracks bolted to the floor and made spacers (out of a million washers) to raise the seats to a good height and had the seat bottoms bolted to and through the spacers to the tracks. I was considering just making new spacers out of 1 1/4" perforated square steel tube and doing it the same way, but since I'll have the welder out is it more beneficial to weld some sort of platform to the floor and mount the seat tracks to that? I'm sure there are a lot of solutions but I figured I'd ask since I may be over looking something much more simple.

Mickey-

I just went out in the garage to measure for you. The tube extends about 11-1/2" in from the back of the door opening to the center of the pipe (at the floor), and 9-1/2" from the floor to the center of the pipe (on the back of the opening). That's approximate, as there is carpet and pad interfering with an exact measurement, and it's pretty cold in the garage... ;)

As far as the spacers- if you decide to go with a fixed position on the seat again, rather than stacking washers, you can make a nice spacer by cutting a piece of steel pipe, and taking a fender washer on both ends. Its nicer than a stack of washers, but still way cheap.

Good luck.

Thanks Stan! You're the best! I hope to get it done tomorrow and I'll post a pic when I'm finished.

Thanks for the advise on the seat spacers as well.

I cut the holes today and come to find out that the vertical subframe bar isn't lined up enough with the frame along the the door sills. No worries. Now I just have to tidy a few things up and I'm going to weld the base saddled to the side of the frame as opposed to on top of it.
It's actually not a lot of work to do it. After the supports are in place I just have to seal everything up with new fiberglass (probably 3-4 layers) and the carpet covers it so there isn't any need for perfection. I'll post pics when I'm done.

You da man, Mickey. I continue to be impressed by your skillz.

Thanks Lane.

Miserable weather today and no room in the garage to get any real work done. I got the support bars cut but that's about it.
If this goes as easily as planned, and adds the structural integrity I think it will, I gotta wonder why VW pan based speedsters aren't made with these. Maybe it's me, but since these cars seem to weaken in this area first this modification is a no-brainer.

Good News and Bad News -

the good news is I got my car up on the lift today and I think I've discovered the problem with the rear suspension. It seems the shocks are too long and are bottoming out, a problem we suspected awhile ago. So I ordered a pair of short shocks and hope that solves the "banging" going on back there. Also did the measuring and marking for the for subframe supports. I'll cut everything tomorrow and if all goes well I may be able to weld the supports into place.

The bad news is I started poking around some of the weak spots in the floor pans and after peeling away some of the fiberglass covering I found a nice size hole (about 1/2") close to the back right corner of where my driver side seats mounts. I'm going to run the car down to a shop that my buddy says will do that kind of work and see what they say. Depending on the cost I may just patch the hole and do the work next fall.
It's always something.

Mickey, if you only have a couple of small holes, hand form metal repair patches an inch or so larger than the hole, scuff the area and apply 3M Seam Sealer as the patch adhesive. Prime and paint. ~Alan

Here's some pics of the holes cut for the frame reinforcements. Slight problem with the verticle post lining up with the frame so that the support will be flush; I'll either have to grind the 45 angle end that gets welded to the vertical post so that it pitches toward the frame more or notch the bottom of the support so it saddles flush to the frame, haven't quite figured that out yet. I may weld a "fill / spacer" (out of steel 1/4" x 1.5" bar stock) to the bottom of the support (to fill the gap) and weld that to the frame so I have a straight line, which I think is the better way to go, but I'm a little concerned about welding "this to that", ect.... I guess if the welds are good enough it won't make a difference.

And Lane, you asked if I had pics of the supports I put up front? The last pic is one of those supports. The front feels pretty solid for now so maybe they're doing their job.

It's still a little hard to tell where I'm at this point because ever since I narrowed the rear the car has been different. I did so much at once it's hard to say what has affected what. I unbolted to the bottom of the shocks and when I drove it today it was night and day in regard to the rigidity in the rear (no more harsh bangs over little bumps). It was soooo much smoother with no shocks which confirms the shocks were bottoming out. I ordered shorter shocks and we'll see how they do when I put them in. If I still have problems it looks like I'll have to come up with competely new mounting places for top and bottom.

Oh yeah, and I'd like a little input on replacing the rear floor section on the driver side. Has anyone ever done that? They sell sections or complete pans and being that our cars are shortened I was curious if replacing the floor pan would require shortening it? I figured since the complete pans are made for original beetles they would need to be cut and rewelded anyway so why order a whole floor pan if you're gonna chop it and reweld it? The forward pan looks to be OK as it is.

I tried to post a jpg drawing of my support alignment problem but it wouldn't load up properly. So, I guess I'll have to rely on you to be able to visualize :)

It's looking like I'm going to have to fill in a gap of about 3/8" between the diagonal support post and the frame that runs under the door sill. Is there going to be a problem with me welding a piece of steel to the frame and then welding the support piece to that? I've never done anything like that so I just wanted to clear it with someone who may know first.

And I'm still looking for some insight on the floor replacement issue. Will I have to cut a stock beetle replacement pan to fit my speedster? It looks like most places are out of stock on the driver side rear section so I may do a patch job instead. Is 20 guage with rivets (and lots of silicone) OK?

I just did the ugliest patch job in the world!!!
As is the case with most "little projects" I went to cut out the rust in my floor and well, let's just say it wasn't "little" when I got finished. I ended up with a 15" x 8" hole in the driver side floor. After a million rivets, and some sheet metal it was patched and pretty solid. I laid a couple layers of fibeglass over it for a little more reinforcement so we'll see how strong it is after that cures. The patch job will do for now but it's looking like a completely new floor pan is in order on the driver side. I'll probably do the passenger side as well while I'm at it, but not until I get the supports put in and the rest of the things I'm doing (carpet, seats, body work, rear shocks, ect...). Once I redo the floors I'm pretty sure that the entire car will be new, aside from the body and frame.