jps tude chassic

Has any body seen the jps tube chassic. It only $1450 more. VW sold thousand of karman Ghia convertable. I will be running a big engine but I still don't see why we need a tube frame.

A tube frame "can" be configured to give you considerably more interior trunk room, foot room, leg room, and seat width room, as you are no longer "restricted" by the original VW architecture. I stil think it's a shame to design a complete frame and ignore more modern constrol arm front suspension. That's just me.

Big engine is a relative term. There are pan based VW frames around with near 3 liter engines in them. Properly built with 2 x 3 steel tubing subframes, they do just fine.

My understanding is that the JPS and Vintage tube frame uses the same fiberglass body molded for the cut down VW pan, so there are no changes in the dimensions of any of the interior spaces (passenger or engine). David Barret, in Fresno, CA was fabricating the frames initially, I don't know if this has changed. The best thing to do is to ask John Steele or Kirk about the frame and the body dimensions. I don't know for sure about the body molds for Becks. It would seem the best you can do is take your Lufkin, and a critical eye, along on purchasing evaluation trips.

An inexpensive option is to contact the seller on the Samba that makes a tube chassis for buggies, All they would have to do is make it a few inches longer to fit a speedsters wheelbase. ~Alan

Beck (Chamonix) makes their own bodies in Brazil. The interior is considerably more roomy - even than the originals, but the floor is raised around an inch, which changes your sight line a bit. The nice part of that compromise is that the floor is flat from door to door, with the exception of the low tunnel. See attached photo.

Lane---very pretty photo!---jack

Yeah, Lane's got nice legs, too!

The pic of the chrome wheel in the rear view mirror is not so bad either.


Marty G.

The JPS tube frame chassis design (square or rectangular steel tubes) is what I would call a hybrid, in that it is designed to work with a VW pan remnant (basically the yoke/fork for engine mounting). One can get a so-called purpose built, full tube frame where no VW pan parts are used. IM does this, and others too, I suppose. In either case you get a stiffer overall chassis than just the pan+body shell combo. Stiffer is better for handling. The JPS tube frame is, as stated, designed to be ~ same floor plan as VW pan, so I don't think you get any advantage wrt interior dimensions. The foot wells and the bulk of the tunnel are built up and so show a little different that a VW. PS: Some holes are cut or left open in the tunnel, allowing acces to R&R cables, etc. I do not know who makes the JPS frames.

I supose a tube frame car CAN be made stiffer than a re-enforced pan chassis, but I'm not so sure that a on a street driven car you would ever know the difference. JPS adds a very substantial 2 x 3 inch steel tube perimeter frame around the entire pan, with additional 2 x 2 inch subframes fore and aft.

Last weekend I re-installed an anti-sway bar. After install, I jacked up the front beam to check bar travel. I placed ONE jack stand under the drivers side cowl subframe for safety. Much later I let the jack down, but forgot to remove the jackstand. The entire front suspension was completely level, left to right, but sitting an inch or so too high. I was really puzzled. I even sat on the front end to bring it down. No change and everything was still perfectly level side to side.

I finally acknowledged my "senior moment" problem and removed the jackstand. Front end came down to normal ride height - still level left to right. I'm just saying . . .

Dave, watch the door gap over your shoulder sometime as you go over a railroad crossing.

There is a difference between a tube frame and a pan.

I don't believe that for a minute....

https://www.speedsterowners.com/forum/readmsg.asp?t=14469

OK, Gordon, but I've owned both. We'll have to agree to disagree on this one.

Yup....I can live with that!

gn

PS, david:

My car has the heavy-duty sway bars front and back, a standard JPS option. The car corners very flat, and I like it like that. Even so, when the car is racked (going over those RR tracks, or other odd pavement angles that tend to twist the car vs., just bump it front to back) it does make some noises: sqeaks or groans -- hard to describe. So something is moving and my assumption is that the whole structure is not as stiff as it could be. I have only my car and one other to compare to, and so I don't know how the pan-only type cars go in similar circumstances, Gordon's claims notwithstanding. Oh, the "other" car mentioned is the Hoopty, and as far as I am concerned, it is the Gold Standard for chassis rigidness. That frame DOES NOT MOVE. [N.B.: while stiff, the Hoopty, according to Cory, is in need of some suspension tweaks to get it to go around corners in keeping with its other race-bred features. Cory says since the car was built by a dragster wrench, it goes in a straight line VERY well, and we all can attest to that. Cornering at speed in the Hoppty (which is where these cars are supposed to live in my book) is still an exercise in guts and faith. One of these fine days someone who understands all about such things will have a chance to suggest some mods and so improve that aspect of Cory's (er, I mean BERT's) car. Who would sign up for that role: Suspension Expert?

I'm glad we're on this because 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

short answer: no, have not heard of these guys. That semafor bug is the real deal. What a collector's item. Good to know they are there.

Mickey, Paul Rich has had work done there.
No idea what the opinion is; I've never visited the shop.

I see nobody has risen to the bait offered to be Chief Drake's suspension guru. There must be someone out there who actually knows how this is all supposed to go. If we had a few inputs here, Cory will have some time to ponder the possibilities and use his drafting/designing skills to figure out what to do upon return. Perhaps.

OK, I can probably help.

What's he trying to do? Get it to corner?

Well, let's see: HE'S RUNNING STOCK BUG SEDAN SUSPENSION!!!!!! DUH!!

I think he's got a narrowed front beam and/or rear axles, or he's not running the wheels out into the wheel wells because the fronts are way in there and the rears are dished out something fierce (and beginning to break loose at the rear hubs).

I would be really tempted to put a widened front beam on there like Dave Klipfel did out West to take care of strangeness in the steering geometry (while still retaining the rack and pinion unit) and get the wheels out to the corners of the car where they belong, then add a 19mm anti-sway bar up front.

At the rear, if I remember right, it's a swing-arm so that limits us in things we can do, but a beefy camber compensator should do the trick, or a frame-mountEd antisway bar (my preference) and, again, get the wheel centerline moved outward to improve balance.

He's running - what? - 3/4 turn on the steering wheel lock-to-lock? so the steering is really quick and skiddish. I doubt if he's running anti-sway bars anywhere now, so it tends to under-steer like crazy (plows) and on and on.

He has one of the best drive-feel evaluators around who can tell us what's happening with the car (Miss Teresa). All we have to do is listen to her and then make it do what she wants. Yes, it's that easy.

Basically, it's a modified, pan-based car. Nothing exotic there, and it can be made to handle like a banshee, especially with that T4 engine (GOBS of mid-range torque on tap, relatively light weight car). All we need to do is get it balanced, get the right tires and wheels on it and have fun. Oh....and maybe slow down the steering a tad....

gn

Didn't Henry Reissner have some tips after he drove it? I can't recall what he said, but I believe that none of them required drastic surgery.

OK, now we're talking. I hope Cory is taking notes. Maybe he's heard it all before, and what is really needed here is a little Nike: Just do it. By and by . . .

Lane, you are right, but I can't seem to remember what Henry said. Were we drinking a few at the time?

"...a few..." Yeah, that's it.

uhhh...quite a few, maybe?....

Somehow, I don't think Lane is ever gonna live that picture down.

and he was supposedly sober when that was taken, too, right?

Not so sure about the sober part. However, despite what that picture looks like, I was absolutely NOT pregnant. I prefer to think of it as bad posture.

That's okay, Lane. You weren't the only one in that room "having a few". Not the only one appearing pregnant ether!

My name was mentioned earlier by Bill George, so I thought I should be sure everyone knows I have NOTHING to do with John Steele. I built four front subframes to be grafted to the rear of a vw chassis for him back when...The relationship was ended by me, after two visits to his shop. I have seen his newer copy of my subs, not exactly what I would put in my car. I do build a full tube chassis for speedsters, two have left here under vintage bodies over the years, and one I drive under my old IM. I am not looking for speedster business, I am just too busy with my manx car chassis. If you would like to get to know me, click down below.
David Barrett 559 876 3217. Fresno
www.manxchassis.com
http://www.youtube.com/watch?v=7rzOiNHTTa0
http://rbcdunebuggy.yuku.com/topic/2160/t/Here-I-go-again.html

I seeee ... Glad this got bumped.

For the record, Henry said "It pulls a little to the left on braking."
Carey said, "I thought it would rattle more."
Lane said, "It doesn't have any wood in it."

I think the real reason that the Hoopty is so rigid is all the steel tie-ins. There are roll bars from the back of a Beetle race car under the front skin, like in a dune buggy, tied to the fully-framed footwell. The footwell is tied to the rear roll assembly by the triangular braces of the door bars, and they're all tied in to the rear by the box-tubing that supports the engine plate. It's essentially a dune buggy with a shell on it, PLUS it's bolstered by that CMC box-frame around the cockpit area.

Apples and oranges to an unmolested pan car, and overkill for most Speedsters' everyday uses. I live in the land of the SUV, though. Washington and Baltimore traffic have already caused me to jump curbs to avoid being squashed -- so however limited the impact protection is, I'm glad I have it.

The real reason for shortening the Hoopty's beam length was to put wider tires on it. The offset of the wheels, the bigger bite of the rack-and-pinion steering setup and the wider tires made it tough to keep the wheels inside the wells (and not rub the footwell or fiberglass) after the car was lowered. I took The Wrench at his word that this was the best compromise. He didn't build cars to turn right and left, just to drive in a straight line.

I don't know if he'd ever run across this before, and it was originally inspired by Parnelli Jones' Baja setup. Kelly's right, though. When the build was in progress, The Wrench did what he knew how to do -- in order to give me what I thought I wanted. I put unfair constraints on the projekt by using a straight-fendered body, so I have to live with the results until a smarter engineer comes along.

If there's a better way, I'll absolutely listen. Too late for this car, perhaps, but maybe there'll be another someday.

I think Ralph Simmers has the answer for the rear suspension. He's got one of the original, spring-type bar setups that mount to the bottom four bolts of the transaxle, and he said he'd modify it for my narrowed rear. It should go from one side of the car to the other, passing underneath the transaxle. It was made for a stock 356, so it'll need to be modified.

It's got knuckles on both ends, so I don't know how he'll modify it without wrecking its metalurgical properties, but he says he can make it work.

The Hoopty does bog a bit in the corners with me at the wheel, and Teresa says it's the way I drive low into the corners. She's a fan of the way Kelly takes them by crossing the middle of the road and sweeping the angle instead of cutting it. She can do exactly the same thing, at similar speeds ... and I haven't broken that code yet.

Teresa and Kelly both drive much more fluidly than I do on curvy roads. I'll take any free knowledge I can get.

Enter wide and hit the apex late...

I'm starting to see some light rust on the Hoopty's brake rotors!

Sounds like someone needs to come and try out some kart racing.

Oh-oh -- my name mentioned again. Just remember: I learned (taught myself) how to keep the car on the road at speed in a very beat up '56 A coupe, and later a S-90 B. I had a lot of OJT. Once you learn it, you never really un-learn it.

There seem to be some elements being tossed around here that would help the Hoopty to corner (anti-sway bars sound good to me, and not hard to do.) and some geometry changes that sound difficult (lots of cutting and welding), but maybe in the hands of ones that know how, could be done. It is what would be needed to sweeten that ride. But even as is, there is a lot of fun packed into that sloppy jalopy aka The Hoopty.