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Old 01-15-2019, 06:25 PM
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i4abuygto i4abuygto is offline
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Default 67 rear spring upgrade question - cross fit

I am looking at raising the rear of my 67 GTO convertible. I am trying to find spring specs on the Safari wagon or Tempest wagon as I prefer to buy over the counter springs.
Does anyone know of the specs on the station wagon springs?
I don't want to custom order a size without knowing fit and I prefer to deal "over the counter".
I know the Grand Prix and Bonneville have approximately a 50-80lb stock gross wt difference to the GTO, which would raise the ride height on my goat by (I believe) to be about an inch.
Do the 67 Grand Prix and/or Bonneville rear springs mount the same as the GTO and are they interchangeable?
Are the fronts interchangeable also?
I will eventually be upgrading to a tubular front end that I believe will sit slightly lower than stock.
I have older springs in now that have sagged some, so my interest is to bring the ride height to a flat rake or slightly higher in the rear.
Thanks

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Old 01-15-2019, 11:19 PM
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Have you thought about air bags and/or air shocks? I'm running both on my 66 and love them. With a 1-1/4" sway bar up and the car stays pretty flat around the corners. The rear is up 4 to 5 inches from stock... with my old saggy springs. Seeing I'm running 8 inch rims on the back with 255/60-15 BFG TA Radials I need the height to keep the tires from rubbing the rear quarter panel lips. I could cut them down but I'd be cutting the wheel well trim to. And that could be a PITA.

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  #3  
Old 01-15-2019, 11:35 PM
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Mike Davis Mike Davis is offline
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Look at the Moog CC501. HD load carrying spring.

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Old 01-16-2019, 08:08 AM
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Quote:
Originally Posted by GT182 View Post
Have you thought about air bags and/or air shocks? I'm running both on my 66 and love them. With a 1-1/4" sway bar up and the car stays pretty flat around the corners. The rear is up 4 to 5 inches from stock... with my old saggy springs. Seeing I'm running 8 inch rims on the back with 255/60-15 BFG TA Radials I need the height to keep the tires from rubbing the rear quarter panel lips. I could cut them down but I'd be cutting the wheel well trim to. And that could be a PITA.
Air bags I can see. Air Shocks put the weight of the car on an area that was never intended to carry weight. You shouldn't need both anyway. I'd replace the air shocks with a shock that matches whatever you have up front.

255/60/15's will fit inside the wheel well just fine - if you're rims have the proper BS.

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Old 01-29-2019, 03:49 AM
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I have done much research on this and I am trying to get an idea of the rake and look prior to buying my front and rear springs. I don't like the stock look of the front being higher than the rear.
I am planning on installing tubular front and rear suspension and was looking at the stock ride height in front and raising the rear. I ran across a tubular kit for the front that actually lowers the front end by approximately two inches by having the springs sit lower in the spring pockets.
It will be an AC car with added weight of front.
By lowering the front springs their claim is "The geometry features include additional positive caster and better handling with a dropped spring pocket (approx 2" lower) compared to stock".
With this upgrade- stock springs in the rear should give me the rake that I am looking for.
Is there anything more that needs to be considered by lowering the front in this fashion.

  #6  
Old 07-03-2019, 12:17 PM
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Quote:
Originally Posted by The Champ View Post
Air bags I can see. Air Shocks put the weight of the car on an area that was never intended to carry weight. You shouldn't need both anyway. I'd replace the air shocks with a shock that matches whatever you have up front.

255/60/15's will fit inside the wheel well just fine - if you're rims have the proper BS.
What is the correct bs to get 255/60 -15 to fit?

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Old 07-03-2019, 12:42 PM
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If you like the way your car currently rides with it's current springs and just want extra height, I would go with an adjustable spring perch. They are cheap and readily available.

https://www.speedwaymotors.com/AFCO-...SABEgIvqvD_BwE

These are used in a lot of class racing to set ride heights, wedge etc. In your case you just use it to get the stance you're after.

You can also do as you mentioned and lower only the front. When using a lowered pocket control arm, it's functionally the same as going to a drop spring. The drawback to this type of setup with a lowered pocket or drop spring is the reduction in compression travel that you have. Personally, I don't recommend this type of setup with stock rate springs. As you lower the vehicle in this manner you really need to add spring rate to keep from bouncing off the bump stops. This is primarily why you see lowering spring kits on these cars coming in for a-body's slightly above 500lbs vs the factory equipment which can be under 200lbs rate.

If you want to use stock rate springs, realistically you want to change ride height by going to a drop spindle. This allows the suspension to retain it's factory compression and rebound travel. The drawback to drop spindles is possible steering linkage contact on the inboard rim and tire with higher backspaced wheels.

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Old 07-03-2019, 04:39 PM
66sprint6 66sprint6 is offline
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I second the air bags. We used the Airlift 1000 bags that fit inside the coils. Part number 60750. We only put about 8lbs. in and what a difference in stance, ride and cornering.

https://www.sdtrucksprings.com/index...oducts_id=7064

We have 255/60's on ours, but on 7" rims. No rubbing. This picture was taken before we installed the air bags.
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  #9  
Old 07-03-2019, 09:50 PM
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Quote:
Originally Posted by Rlfehl View Post
What is the correct bs to get 255/60 -15 to fit?
Depends on the width of the rim and which rear end you have.

I used to run 255/60/15's on my '64 GTO on 15x7's with 4.25" BS. They cleared, but it was close.

My car has the 1" wider 12 bolt rear end. With a stock rear end you could get by with 4" BS and very possibly 3.75" BS on a 7" rim.

On an 8" wide rim, add .5" BS.

  #10  
Old 07-04-2019, 01:23 PM
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Thanks for the responses. I put 255/60 -15's on 8" Cragars with a 4 1/4 bs and they were tight, passenger side hitting just sitting, not moving. I am returning those wheels and getting 15x7 with a 4" bs. That's all that is available. I have a 10 bolt rear end. One problem is the passenger side rear 1/4 was replace and has a bigger lip than the drivers side. Hopefully new springs and 7" wheels will cure the issue...and maybe air bags...I just don't want to start cutting on the lip...although still an option I guess.

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