# 1969 GTO Convertible suspension questions - want to lower



## Heatwave (Nov 30, 2014)

I own a 1969 GTO Convertible (AC). It's a great car in perfect running condition with a 4 sp 200 4R OD auto. It rides terrific at 75 on the highway but its stance is very high and definitely would not be defined as a "tight" ride on the road. When I bought the car, it had "cut" springs and a very low ride. Too low and rubbed on too many driveways. I installed new "stock spec" shocks and what I thought were "stock spec" coil springs. Specifically Prosteer Coil Springs FCS5377S in the rear and Prosteer Coil Springs FCS5376S in the front.

The factory ride height measurement should be 9.6" height at the rocker panel at 32" behind the front wheel and 9.1" height at the rocker at 19" in front of the rear wheel..

Important to note that I have 15" Rally II wheels with 235/60/r15 BF Goodrich Radial TAs (overall diameter 26.1") on the car. The original factory tire and wheel was a 14" wheel with G78x14 tire (overall diameter 27.1").

So just based on my current tire/wheel combo I should be .5" LOWER if all other suspension components are the same.

My problem is the ride height, even after 2 years and a couple thousand miles, is 11" at both the front and rear rocker panel measuring points. I have approx 3" of "visual" space between the top of the tire and the chrome wheel well trim.

I want to change out the coil springs but am struggling with the right ones to use. I really have no way to know what the relationship is between the Prosteer coils currently on the car and any other spring. I really want a lower stance but is a 1" coil drop spring the right way to go? Any help would be appreciated as to the right spring for my 69 GTO and tire wheel setup.Thanks


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## Researcher (Jun 29, 2020)

If you dont want to guess and hope to get the drop you’re looking for you could consider adjustable coilovers. That way you can adjust it to what you want. Expensive but full ride height control.


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## roger1 (Jun 25, 2020)

Hey Heatwave what did you end up doing for replacement springs?

I've got a '69 convertible with A/C that I'm putting together and need to decide what to do about coil springs for it.
The rear springs I have for it are original but it appears the fronts were replaced. They have the number 5386 stamped on them which correspond to the Moog part number for 1968 convertible w/AC front springs. But '68 and '69 springs aren't the same. And, I'm going to have some weight reduction up front compared to stock. I'll be using an aluminum intake manifold, an aluminum radiator and possibly an aluminum AC compressor. Added up, I figure that's going to be about a 75 lb reduction. I'm a little concerned my car might sit too high in the front with these springs.


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## Heatwave (Nov 30, 2014)

roger1 said:


> Hey Heatwave what did you end up doing for replacement springs?
> 
> I've got a '69 convertible with A/C that I'm putting together and need to decide what to do about coil springs for it.
> The rear springs I have for it are original but it appears the fronts were replaced. They have the number 5386 stamped on them which correspond to the Moog part number for 1968 convertible w/AC front springs. But '68 and '69 springs aren't the same. And, I'm going to have some weight reduction up front compared to stock. I'll be using an aluminum intake manifold, an aluminum radiator and possibly an aluminum AC compressor. Added up, I figure that's going to be about a 75 lb reduction. I'm a little concerned my car might sit too high in the front with these springs.


i decided to go with the Ames front and rear springs that were specific for my year, convertible and AC. They were a perfect match. The ride height is within less than 1/2” of the factory specs. Ride is terrific and the cushiony ride was cleaned up nicely.

i have just a very slight touch of the front wheels on a hard turn to the steering stop on certain inclines but its so slight and rare enough that its a non-issue. Its more related to the 235 tires than the Springs since I had a very slight rub with the previous springs. 

I would recommend just getting the exact springs for your setup directly from Ames.


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## roger1 (Jun 25, 2020)

Thanks that is helpful info. Are Ames springs powder coated?

If I do go with new front ones from Ames, I'm wondering if it would be better to get the non-A/C springs because of the less weight I'll have up front with the changes I'm making.


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## Heatwave (Nov 30, 2014)

roger1 said:


> Thanks that is helpful info. Are Ames springs powder coated?
> 
> If I do go with new front ones from Ames, I'm wondering if it would be better to get the non-A/C springs because of the less weight I'll have up front with the changes I'm making.


Good question. I’m not sure if they were powder coated or just black gloss paint. They have terrific techs at Ames. I recommend getting the part #s from their online category that most closes matches your stock setup. Then call the Ames techs and they should be able to help you better match the springs to your setup.


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## gomer45 (Jul 19, 2017)

Heatwave said:


> i decided to go with the Ames front and rear springs that were specific for my year, convertible and AC. They were a perfect match. The ride height is within less than 1/2” of the factory specs. Ride is terrific and the cushiony ride was cleaned up nicely.
> 
> i have just a very slight touch of the front wheels on a hard turn to the steering stop on certain inclines but its so slight and rare enough that its a non-issue. Its more related to the 235 tires than the Springs since I had a very slight rub with the previous springs.
> 
> I would recommend just getting the exact springs for your setup directly from Ames.


That sounds like a great setup! We'll be working on buddy's new '69 GTO Converti project soon after we finished installing the suspension from 4 Wheelonline onto the truck this week. He's still yet to decide to get the adjustable coilovers or stock spec.


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