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Discussion Starter #1
I've fitted shorter, stiffer springs to my '74 GTV, and a set of Bilstein shocks.

Part of the process involved removing the axle limit straps to swap the rear springs. I've put them back on, but removed the 1/2" aluminum spacer thing between the strap and chassis, assuming it was a high ride-height US-market item to give more droop travel to the axle to match the taller springs. Now I've got 1/2" more bump travel, but 1/2" less droop travel, which might excessively unload my inside rear tire while cornering.

I've seen pics of these spacers still installed on lowered race cars, so I'm wondering if I've done the wrong thing by removing them.

Anyone know exactly what they were intended for?


Also, why on earth does the car need axle limit straps in the first place? I've only ever seen them on monster trucks or off-road race trucks with massive tire and axle weight which threatens to tear apart the shock's rebound limiters.
Every other street or race car (or motorcycle) in the known universe uses the shock's rebound stops to limit wheel travel. Can't my Bilsteins cope with this? Are the straps necessary?

This is my first Alfa, so I'm still wrapping my head around its design "features".

George
 

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One thing that I have learned is that if the Alfa engineers put something on the car, it should stay. Unless you are really sure that you know why something is better gone, really, leave it. These Alfa guys were pretty good at the engineering thing.
Yes, I think that you should put them back.

I'm amazed that you didn't post about what a PIA it was to get them off. I had to cut the heads off the screws to get mine off.
 

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Discussion Starter #3
Actually, the screws came out easily. I was expecting a fight... but I guess I got lucky.

I agree with *some* of your reasoning that original engineering is hard to improve on... but I've seen enough compromise solutions in countless other cars (Alfas included) that were done for dubious reasons. Especially cars from the early '70s, when manufacturers struggled to keep up with stricter government regulations, and often slapped band-aid solutions on old pieces just to keep selling cars.

Some brilliant/elegant engineering shows up in the most mundane/crappy cars (various FWD GM family cars, for example, with excellent engines or electronics), while some formerly sporting cars get burdened with parts to satisfy government regulations in diverse world markets (MGBs and Alfas and Porsches, for example, that in the early '70s got tall springs just to satisfy US headlight height laws, but were never engineered for taller ride heights). And, of course, most production cars are enineered and built to brutal cost limitations, so I'll never assume that just because it's on the car, it's a good thing.

I've kept the axle limit straps, figuring there's some good reason for such a system. But they still bug me. In my mind, cloth suspension pieces belong to the same era as leather sandwich friction dampers. Quaint, charming, very Alfa, but...

I'm guessing those aluminum blocks are part of the US ride-height thing, but I'm not sure. Is anyone sure?

And does anyone know if there's some unique feature of the Alfa shocks or rear end design that prevents them from serving as rebound limiters, like every other shock on the planet?
 

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The shocks are not designed to limit travel, but could be if you really wanted to. The fabric straps actually work really well - imagine them to be a space age composite poly-acrilyic polymer with enhanced flexibility properties if that helps (BTW, made all that up). Some say they are too short and cause an inside wheel to pick up. I say if it is rolling THAT MUCH, it was going to pick up anyway.

You need to keep them to make sure the springs are captured on full droop (note that some aftermarket springs require SHORTER straps to ensure capture - a trap for some).

Also, GTV6's racing in Group A in the early 80's adopted a similar approach to the de-dion to limit travel (so it has racing providence)

Re the alloy spacers, not sure why they were there, but I removed mine also to get a bit more bump travel before getting onto the bump stop, but that was for a track car running lower and stiffer springs. Not completely certain that without them you wouldn't have the diff housing hitting the underfloor a bit hard on full bump (do you jump your car?). There is a little rumber bump stop on the diff for that, but its not much given the potential energy involved.

For a road car, I'd probably keep them in, just for peace of mind on big bumps.
 

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'Shorter springs' would be all the answer I needed.

The limit straps as designed help prevent damage to the shock in full droop and to keep the stock length springs in thier pans while at that full droop.

If you put in shorter springs, they'll certainly stand a fair chance of displacing on one end or the other well before the shock gets to full extension without straps (preferably adjusted by some means to shorten the allowable travel to suit said shorter springs) to halt the process before it's too late.

Counting on the shock alone to do it is begging for trouble IMO.
 

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On a more mundane note, you can't jack up the rear and get the wheel off the ground with the standard body jack if you don't have axle straps. And using the shock as an axle droop limiter is a good way to wear it out/break it.

Andrew
 

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Discussion Starter #7
1" rear shock spacers

Just an update about the spacers, with an interesting observation.

I installed a set raised rear shock mounts (similar to the Autodelta replica spacers sold by Alfaholics), since my car is lowered, and the shock spacers move the shocks back into the middle of their operating stroke and prevent them from bottoming out. These raise the rear shock mounting about 1".

Now, with 1" lifted shocks and the little 1/2" limit-strap spacers removed, the shock reaches full extension and the limit strap stops the axle at the same time. Almost like it was designed to do this.

If the limit-strap spacers were retained and the shock spacers installed, the shocks would reach full extension *before* the limit strap would stop the axle, rendering the straps useless.

BTW, I'm using Bilstein HD shocks, which I think are the same length as the stock Spicas.

George
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'74 GTV
2" lower, Bilstein shocks
 
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