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Rear spring longevity & swapping.

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vping

vping

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Do the rear springs on a B, under normal driving condtions, last a long time? The reason I ask is this. While awakening the 74B, I noticed the the rear shackles looked odd. I compared them to the ones on the 74GT and they are different. The roadster looks like someone made them and they are about an inch or two longer. Did they do this to make it look cool & jacked up, or did they do this because she was settling a bit. So the real questions are, how well do the springs hold up & do they settle significantly over time?

I can pull the spares off the GT and add them to the B cause my guess is that higher is not better. While I am at it should I pull the springs out of the GT, re-furbish them & swap them out with the B. Are they compatiible?
 
I'm not an expert on this by any stretch of the meaning, but I do believe that the GT springs are stiffer to compensate for the added weight over the rear tires.

They are probably the same length, and as such will more than likely fit on a roadster. However, I think you'll end up with the same situation as you had before; the rear of the roadster will be sitting "high". Also, GT rear springs are 7 leaf where the roadster rear springs are 6 leaf...
 
GT springs are stiffer, no other difference. Springs should last a very long time. My original set lasted over 30 years and still worked fine, then were just sagging a bit.
 
But sagging a bit, would you really need to put a 1" to 2" extension on it?

Do you recommend or not recommend swapping out the B and adding the GT springs. I knew they were 7 vs 6 leaf, I'm just not sure if they will be too stiff on the B.
 
GT springs will be very stiff. You don't want to run the rear too stiff on a B. It will get really squirrely on rough roads. The factory race cars ran extra soft rear springs in competition.

I can't imagine why someone installed 2" extensions on the shackles. I would repalce them with standard ones. If the springs are sagging, you have three options.

1. Replace them both and pray your car doesn't sit too high and lean to one side.

2. Have your current springs re-arced by a spring shop.

3. have a set custom made to your specs from a spring shop.
 
Or, OR, take em apart and useing a big hammer arc them your self like the racers do.
 
Not only are GT rear springs stiffer, but they've got a couple more leafs...if you slide up underneath & count, you'll see the difference readily.

That said, MG rear springs last a long tie but over a lifetime, they do sag (especially the driver side)....however, both the roadster & GT used the same shackles so a DPO mod there could be to correct some sag or to jack her up ala Bubba!
 
WOW. I don't know what they were thinking but stock center to center is 2 1/2". The B has 5" C to C. What the heck for?
What could I be missing? How much sag could really be there that would warrant a 2 1/2" lift at the rear shackle?

Here are the GT parts car and then the B.
7-30-07-74saggingsprings003.jpg

7-30-07-74saggingsprings004.jpg
 
And here is one of the side of the car. The tires are Mud/Snow 155R14 crap that are coming off as soon as I get the Superlites.
7-30-07-74saggingsprings.jpg
 
Nah, that's a homemade lifter kit...bet its not for sagging springs either!
 
If I switch it back, I'm good right or did the DPO screw something up permanently by adding these?
 
Switch back & see what happens with your springs...
 
You're good, so long as the springs aren't sagging so badly that you bottom out on bumps. Regardless of the condition of the springs, you should start making things right. If you need springs, then you need springs. There is no way around that other than to become a DCO by leaving it the way it is!
 
May have had snow tires at one time??
 
Not sure if he used it with snow tire or stored it with them on it. It had several different types of tires on it and the extra rims he gave me had very dry rotted tires on them. Car sat on Blocks & jackstands in the garage for 9 1/2 years and outside on blocks & jackstands for another year and a half.
 
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