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Fellas, I'm in the pan building portion of my buggy auto-X project, and pretty soon I will need some shocks. From what I have read, Koni adjustable shocks will be going on front & back.

I will have a *slightly* lowered front using beam adjusters. At what point do I need to look for shocks for a lowered front end? Is there a magic number? Will the Koni accommodate a couple of inches of drop?

Adjusters can have other uses besides raising and lowering the front of the car. If you set them up (adjust) differently you can change the spring rate to a certain extent besides just the height adjustment. There are also other mods you can do with/to the torsion bars also but some of that depends on K&L or BJ beams (65 and later is BJ, before that is K&L).

Brands of shock I can't advise other than make sure they are designed toward how you are going to use them and there are many designs available.

Lee

I used Koni's on my pan car, it was ball joint with drop spindles and fine tuned with beam adjusters. I had great success with Koni's, much better than Bilstein's for me. The Billy's were to stiff and the gas pressure raised the ride height a bit at the front
Is yours ball joint or linkpin?
Are you using drop spindles?
If you'd like I'll measure the closed length of of my Koni's if that might help?

Before you buy shocks... if you are going to run adjusters for lowering only then I would install them, find the ride you plan on using then measure so you can buy the correct length for shock's worse case compression. I have hit a "no-see-um" once that was so hard the piston in the shock jammed against the rounded edge of the shock and it took 3 of us to bust the jammed shock loose.

If you are going to use the adjusters to change the "spring rate" (you can do the upper tube for this only if you want but the drop won't change much if that is what you are after) but still I would do some measurements for shock compression.

You can adjust both tubes differently for lowering and spring rate but still measure for the worse case situation.

On BJ beams there is another way to play with the spring rate but you have to be careful when you do it and this is because of the torsion bars shape and the accommodating/mounting shape of the BJ adjuster and the trailing arms shape for accommodating the torsion bars.

Lee

Ian, Lee,
Thanks a bunch for your responses.
The car has the ball joint front end. I do have drop spindles and torsion adjusters. My hope is to get most of the lowering done with the spindles and fine tune with the beam adjusters.

Any help with workable part numbers would be very helpful. Thanks guys!

Sounds like a good start.

Is the fuel tank going to be retained in the stock location in front? Moving it can change things quite a bit which, while it isn't necessary a bad idea, does change the balance of things especially when a full tank has the fuel sloshing around. The center mount style of tank has definite advantages especially when you are going to go "nose down" some. My later model fuel tank leaked out the fill cap when parked nose down. Remember to protect it from being bumped into .
Front suspension. On Baja Buggies the front end is backed up by these brackets. The beam connects to to the pan mount and the connections to the pan are considered fairly close together. The loading, when playing around, can cause the front mount to twist some but that twist is accentuated more at the ends of the beam. Also, because of the mounting so inboard the beam is not supported well past the mount so a hard hit to the suspension can cause the beam to get bent (Jeff Hibbard in his book "Baja Bugs & Buggies talks about it and shows a pix of a bent beam on page 55). Will it happen to you... probably not but I also try to be prepared for the unthinkable. Remember, you are dealing not only with an inanimate object but other drivers .

The pix shows both the upper and lower commercial supports in place. There are two slots towards the front on each side of the main pan which was for bolting the body to the pan with the slots allowing expansion and contraction of the two metal assemblies (the pan and the body). The lower commercial support does bolt to it and the beam but the upper support, which would bolt to the metal firewall of a bug does not sit right in a glass buggy and the glass isn't strong enough to support the support when needed.

Since the upper and lower supports can be purchased separately I would recommend using the lower one. I am having problems coming up with a design for the upper one partly because of the glass body and where the firewall would need to be broached as it would be very close to a structural corner as the mount to the beam and the shape of the pan are kind of at odds. Rails can do it easily as the body/pan taper isn't there but the glass bodies are a different matter because of the body and pan taper.

I run a glass bodied bug in the sand but a lot of the same problems I run into would/could apply to your build especially if your toy has a street legal/ use also.

Lee

I had drop spindles adjusters and beam stiffeners, my beam was 100mm off the ground and I used the stock length adjustable Koni 80-1787
there is also a short one for really low cars.
for an IRS rear, the part number is 80-2149
aircooled.net has them at a decent price i think

That is exactly the kind of info I was looking for. Thanks Ian!

Ian,
With the Koni shocks ordered & delivery pending, could I get you to make a suggestion for shock settings on a fiberglass buggy?

I expect I will set them in the middle for starters unless you have some other ideas. Thanks much for your input.

FJCamper your info on this forum has been tremendous and If you have ANY input at all, I would take that, as well.

Enjoy your weekend everybody.

Remember that the glass body is going to be much lighter than the stock body setup and not as strong (I have 2 of them).

You should look at ways of stopping pan twist/flex such as by adding a cage... not just using the old fashion show hoop. I'm not sure about the strength of the cages you can buy on line for Bajas as they are "halved" so you have to put them together but... they could be stronger than the ads sound too. I know of one kid who was killed in a roll over in his glass buggy on the street with only a show hoop for protection.

Are you going to keep the stock tank up front?

Also I recommend using a earlier center fill fuel tank assuming the body isn't already cut for the later front fill fuel tank. The front fill tank, when full can leak out the cap (make sure that it is new) when going down hills.

Lee

Lee,
As always, thanks for your input. I (hope) I am going about this logically. Please tell me if you see something otherwise.


1). My first goal is to get a rolling chassis again. Included in this process is (are?) shocks, wheels & tires. Once it is a roller again...

2). Set seats in the buggy. Once seats are in and seat elevation is determined...

3). Determine, order & install windshield. Once windshield is in place on rolling chassis

4). Roll chassis with body temporarily installed, seats and windshield to fab shop capable of building cage, including steering column support.

The buggy will have a traditional early VW fuel tank mounted in the usual (front) location (with auxiliary tank supports) for weight balance. Possibly a battery as well in the front.




After ALL THAT, the body will go on for the last time, wiring and plumbing can begin and motor building can commence.
What am I missing or forgetting?

Slayer61, I ran full hard on the rears and 1/2 hard on the fronts in my Ghia, so maybe start 1/4 hard at the back and full soft at the front and tighten as necessary to stop the car 'bobbing' on rebound. Keen to hear how you go.
thinking of other thinks while it is apart, get a good steering damper (boge or koni if in the budget) and check you have plenty of caster, say 6 degrees to start. Usually 1 set of caster shims with get you into this ballpark.
I know it is nice to see lots of rake, but if you want to turn fast and controllably keep the car pretty level.
good luck

Excellent. Thanks Ian. I installed the shocks over the weekend, and not having a starting point, I set them all in the middle. I will get them sorted as per your instructions. I appreciate the other advice re: caster and steering damper as well. Thanks mate.

slayer61 wrote: ↑Fri Aug 13, 2021 10:27 am Lee,
As always, thanks for your input. I (hope) I am going about this logically. Please tell me if you see something otherwise.


1). My first goal is to get a rolling chassis again. Included in this process is (are?) shocks, wheels & tires. Once it is a roller again...

2). Set seats in the buggy. Once seats are in and seat elevation is determined...

3). Determine, order & install windshield. Once windshield is in place on rolling chassis

4). Roll chassis with body temporarily installed, seats and windshield to fab shop capable of building cage, including steering column support.

The buggy will have a traditional early VW fuel tank mounted in the usual (front) location (with auxiliary tank supports) for weight balance. Possibly a battery as well in the front.

After ALL THAT, the body will go on for the last time, wiring and plumbing can begin and motor building can commence.
What am I missing or forgetting?

On your last statement I said the about 30 years ago .

What you stated it what I am going through on my black buggy (I also have a blue buggy that is used only on the sand like my black buggy will do also) for a long, long time.

Your #1 statement I think I might hold on that as shocks seem to be redesigned so frequently now days.

I also would get and install a Truss/Kaffer bar even if this is to be used only on the street for cruising only. If you are going to play harder later then you will need it for sure. It helps support the trans mounting forks to keep the engine and trans from dancing around under other than freeway/street use only.

#2 Seats If you are going to use car seats then be careful on the mounts as the stock mount will set you up so high that your legs can be even with the top of the access lip on the body. You will want to be down lower for what additional protection the body can give from not only side hits but being thrown around on the rough roads/trail or side hits. Make sure that they are adjustable fore and aft for changes in your freshness or being tired with the steering column location also being part of this.

#3 The windshield is important for protection but it's height is at least partially relevant to the seat height and location. With the seat sitting too high can put one's vision over the top or the windshield frame could be in the vision way. Something people often forget until the windshield is blocking their vision.
#4 Cage The top pix was taken the day that the buggy came back after the cage was built (this was done in the early 2000s) and if you look closely you can see it.

The bottom pix was taken after the body lift was made and the cage was attached to it. One of several things that the cage doesn't have is the cross bars in the rear and side bars for additional strength in-case of a rollover.

I took the windshield off due to two reasons: on the sand where we ride, if you have a windshield then you must have a windshield wiper setup and the wiper arms and blades were in a too close of fit (this goes back to #3). Also, since I ride on the ocean beach the air is salty so the windshield gets the salt over it and it blurs one's vision. Also, since the air curls around the windshield it get the inside of the windshield salt covered also. Solution... no windshield in this case since is isn't required where I ride (I still have all of the stuff taken off).
I attached my steering column support to the front cross-bar of the cage. It was mounted on the buggies' dash but this is a stronger safer way.
This is part of the mockup side bars for the cage of my black buggy. While just a mockup it wasn't finished; the second pix shows the front hoop rough location and the side bar will be bent up to join to it. At the rear of the side bar where is bends down there will be a diagonal brace to the rear hoop and there will be additional diagonal supports down the sides of the side bar. I got this idea from one of the guys who posts here and he rides very, very hard.

Remember that a glass buggy body does not have a roof or side walls (including doors) to transfer loads around from front to rear which normally would be the body's job to support the pan. This is one of the reasons why the body lift was added.

I am not a big fan of the battery and fuel tank so close together especially when they are joined in a enclosed place.

Just some thoughts which hopefully helps or gives you ideas.

I forgot to add... is the body lift necessary... probably!
This is a doubler I made to go under the body lift using the channel for the body to pan fasteners to go in.

Where I made the mistake was to use 1" X 1" square tubing with a fairly thick wall. Where the mistake showed up was when I put the seats in place but the body was not bolted in place... just sitting in place. When doing a fit check for seat location someone tall and someone shorter sat in the seats but the pan bowed then when they got out then the slightly bent tube more or less held the side of the pan in place. I used the tube as I wasn't sure (since I was riding in the sand bouncing around) the thinner material of the pan floor would have been strong enough. I have seen dam(N)aged glass bodied toys ridding on the sand before.

I should have used rectangular tube with the long side vertical; say 1" X 2" or deeper. This would have worked like a slide when off-road but the bolt bottoms and nuts would have been in the way for it to work as a slide. But... it would have worked like the body lift but the body would have stayed low like a street buggy would like.

Again, thoughts for what they are worth.

Lee