Carlos G posted:

Excellent drawings, Jim.

Now I need to get off of my ass and build up mine, but someone put this idea in my head that I need to fab up one of these.

Clam shell bracket

What to do, what to do?

I like the holes! Drilling all those inline is a skillset all by itself!

JR Gilbert - Madison, Mississippi posted:

I am also a member of spyderclub. Posting information here is much easier.

You can say that again, Jim! You have to downsize the photos to a tiny 150Kb or less, ruining any chance of seeing actual detail.

Great job, Jim. Lenny and I are working on the same thing for our cars. I'm going to weld mine up in one piece, then heat-treat to Rockwell 40 or so. 5/8" bar and 3/8" flat steel ends. I'll post pictures.

This is the like the clamshell holder Ed made from aluminum. Mine is steel and made by Carey Hines and Co. I really love it, it works REALLY well. Driver's side on my car.IMG_20170516_150113062

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I made a bar also. I used plasma cut end levers, urethane sway bar bushings(5/8"), 10mm rod ends for end links, a coupler nut on the bottom shock bolt, and a recycled 911 early through-body bar. 

I had to fabricate brackets and weld them to the beam. I had the bar Tig-welded so minimal heat was put into the bar. It was pretty straightforward to build.

Road test tomorrow, it's going to be nice.20180426_15214220180428_11200220180428_11194920180428_112032 

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Jim Gilbert - Madison, Mississippi posted:

As far as the rear goes; nothing right now. My car is an early Vintage with coil over rear shocks. Some say that because of that arrangement it's about as good as it gets. I'll drive for a while and see what happens.

Thanks for your reply.

Jim

@Jim Gilbert - Madison, Mississippi

"Coil over rear shocks" I've never seen that on a Vintage.  Are you sure it's a Vintage? 

Troy, we're over here on the "Spyder" side of the site, and we're talking about Vintage Spyders from Vintage Motorcars, not Speedsters.

Vintage Spyders have a space frame tubular chassis, fabricated tube trailing arms, and coilover shocks. No torsion tube in the back.

I really like what you've done, I've thought about doing something like that for a while. The only suggestion I would have is to really watch the lower shock bolts. You've put a big reversing load out there at least an inch or two and you may see them fatigue. If they come loose or if they ever look bent that would be a sure sign that they are fatigued.   

I hear you, Chris. Is there a way to replace the stock shock bolt with anything longer?

The load factor was the one of the reasons why 5/8" bar(actually 15.25mm from early 911) instead of a 3/4". I had re-bent a factory link-pin Bug bar so it cleared the frame tubes by the bottom torsion bar. But the new car above has a 2" narrowed beam, so it wouldn't fit. The 2" narrowed EMPI 3/4" bar hit the frame no matter how I bent it.

The early 911 and 912 rear bar had sway bar links with plastic snap-on ball links. How much load could be transferred by a plastic link on a 15mm bar? I don't know but made a guess that it would work. I'll find out soon enough...... 

So today was about 78 and sunny so I got to take a ride. The anti-sway bar works perfectly. I am very pleased. The car corners very flat without understeer or oversteer. I would say it's the most neutral Spyder I've ever driven.

So, a big thank you to Carlos G for the original idea and Jim Gilbert for sending me photos of what he built.

Jim, did you heat-treat your bar after the splines were cut? I have the old book "How To Make You Car Handle" and in it they recommend 4130 steel(exactly like you used) but they heat-treat to Rockwell 38-42 after machining. That is the reason I used the old 911 bar and Tig-welded it to my lever arms.

DannyP posted:

So today was about 78 and sunny so I got to take a ride. The anti-sway bar works perfectly. I am very pleased. The car corners very flat without understeer or oversteer. I would say it's the most neutral Spyder I've ever driven.

So, a big thank you to Carlos G for the original idea and Jim Gilbert for sending me photos of what he built.

Glad to hear it turned out so well, Danny!

Very nice Danny.

I did not have my bar heat treated. The local service would not do it without a specification. I'll contact them again and see if the numbers you provided are enough.

Thought about using steel arms and welding them to the bar but I have a front oil cooler and there are oil lines in the void area. I would not have been able to get the bar in.

I was concerned about using the shock stud because of the length of it's arm. Adding the coupling and the heim joint doubles the effective arm of the bolt. That's why I chose to use a welded on mount for the lower link connection. I'll be curious to see if you get any bending.

I have about 500 miles on my bar and have moved the link to the #1 hole in the bar. I started out with hole #3 but had some oversteer.

Been thinking about a z-bar for the rear and had started the machining, but after furthur consideration I think that the coil over shocks limit the movement of the swing arm more than the original VW design. It may not be needed. Any thoughts on this would be appreciated.

Good job.

 

It was definitely a tight squeeze with the straight arms, would have been much easier if I had angled them like you Jim. I'll keep an eye on my shock bolts and couplers for any bending.

I have the front bar at the furthest adjustment out(least anti-sway) and so far so good.

LennyC is building a z-bar for his Vintage(2001). I am unsure if it will work much because as you say the travel is limited. I put down-travel-limiting straps on my axles and am currently trying that out. I took my old 2" lap belts and attached at the top shock bolt. Then wrapped around the axle and the adjuster. They are as tight as I can get them at normal ride height which limits the downward travel to about 3-4 degrees. All in an attempt to completely eliminate that outside wheel tuck.

As an aside, according to QA1(my rear shock manufacturer) there is supposed to be something other than the shock limiting travel. I also have a front shock bushing around the piston rod to cushion the full compression travel.

Kind of a backassward arrangement to mimic the original Spyders travel limiters on the frame.

Do you mean the black dust shield on the front Koni? I got them from cip1.com, they are for stock Bug shocks, they screw onto the Koni piston rod and include the pin that has the rubber bushing top shock mount.

I have pretty much the same thoughts as you on the Z-bar.

An update on my swaybar:

I've run it for several hundred miles now on the street. The car does not exhibit any understeer or oversteer. No bending of coupler or lower shock bolts to date.

Planning to do a DE at LRP at the end of the month. I'll let you know how that goes. 

Sweet.

How are the rear limit straps working? Summit has some 8" limit straps that I think I can get to work.

I installed some rubber bumpers on my front shocks, but I cut them down. They would've been too tall if I've used them as is and would've made the shocks a mute point. So far, they've prevented tire rub, but I haven't tested it on that one certain curve with that certain bump that always causes the rub.

I still have a sway bar on the list though, with a few other things.

The anti-sway bar performed perfectly at speed along with the limit straps. The car is VERY neutral at 8-9/10s. Didn't get to 10/10s. Throttle steering worked well, as well as a bit of trail-braking to rotate the car at turn-in. Perfect compromise between a comfortable street ride quality and track-day handling.

This is what I was thinking for the limit straps.

Limit straps 2

I tried some exhaust clamps at the bottom, but they're too short. I'll have to fabricate a couple. I was thinking that this clamp can be slid up the axle to adjust the tension on the strap, then clamped down to secure it so it doesn't move. When I fabricate the new clamps, I'll probably allow some room for some rubber between the clamp and axle. I don't know if this is needed or not. The top strap attachment might also need to be bent slightly so the strap doesn't rub the shock spring.

We have a term at the shop, ABT, always be tweaking.

 

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