QUESTION: NEED HELP

ZAY1975CONVERTIBLE

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melsg5

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I just looked in the 1983 Pontiac parts book.
1. You really want to lower the car 2" in the rear?
2. The Grandville convertible weighed more than the other two vehicles.
3. Once the base weight per corner is established, 894 for your car, the options are added on to establish total weight.
4. There is a chart based on total weight and whether firm ride with at least 3 different springs.
I'll scan and post the two pages later.
They will physically fit but what ride height you will end up with is unknown.
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cammerjeff

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You can call Detroit Eaton Spring, they made the original springs for your car, if you explain what you want to do I am sure they could make a set of springs that would work for you.


I have used them in the past and they were very willing to work with me on a very uncommon car. My old 67 Sprint 6 Lemans
 

ZAY1975CONVERTIBLE

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I just looked in the 1983 Pontiac parts book.
1. You really want to lower the car 2" in the rear?
2. The Grandville convertible weighed more than the other two vehicles.
3. Once the base weight per corner is established, 894 for your car, the options are added on to establish total weight.
4. There is a chart based on total weight and whether firm ride with at least 3 different springs.
I'll scan and post the two pages later.

I do. I'm looking for more of a "squat" look. I want the rear to sit just a little lower then the front. I seen these springs which run about $129 of my other choice would be QA1 coil overs in these rear which run about $600 but are adjustable. Pic for attention on how I want it to sit, I know its a Chevrolet but its a B body.......AND NO im not putting those size wheels on. lol
 

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melsg5

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Here's the chart and Moog has specific springs listed for the Grandville
 

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ZAY1975CONVERTIBLE

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You can call Detroit Eaton Spring, they made the original springs for your car, if you explain what you want to do I am sure they could make a set of springs that would work for you.


I have used them in the past and they were very willing to work with me on a very uncommon car. My old 67 Sprint 6 Lemans
Thanks bud, I'll look into that!
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melsg5

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Concerning your picture, just remember front end alignment may become an issue
 

melsg5

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I just looked at Eaton and strangely they do not show the Grandville or any convertible B body for 75 but look at Moog as I posted above.
You can also cut the springs you have now if they are not variable rate.
 

pontiacgp

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I went with Moog 5557 springs on my 76 Grand Prix which was supposed to put my car at original height but now it is all jacked up in the rear and looks bad in my opinion. I have looked into OPGI lowering springs too but have not decided yet what to do.
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melsg5

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I went with Moog 5557 springs on my 76 Grand Prix which was supposed to put my car at original height but now it is all jacked up in the rear and looks bad in my opinion. I have looked into OPGI lowering springs too but have not decided yet what to do.
A better choice would have been CC507, a variable rate spring.
 

melsg5

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I can't guarantee that but a variable rate is softer on initial compression and becomes firmer as compression increases.
Did you notice a difference in coil design between the original springs and the 5557?
 

pontiacgp

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They look pretty much the same I'm pretty sure. I didn't compare side by side before putting on my car. Looking at your car in your avatar looks to be a little lower in the rear going by height of rocker panels and that is the stance I am looking for. The rocker panel should be an inch lower in the back compared to the front , that is what the specs says that I have for a 1976
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melsg5

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This thread has only two avatars yours and my 71 GTO. The thread itself concerns a 75 Grandville.
 

ZAY1975CONVERTIBLE

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Thanks for the info guys. It's looking like I'm gonna go with the adjustable coil overs from QA1. I can get up to 2" of lowering with18 points of adjustments from soft to hard.
 
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