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Discussion Starter #1
Does anyone know the diameter of the front sway bar? Is it the same as what came on a LeMans?
 

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Does anyone know the diameter of the front sway bar? Is it the same as what came on a LeMans?
The GTO restoration book says all front sway bars were the same for 1964-67 - 15/16" outside diameter. I would assume the Lemans or Tempest with the V8 would be the same seeing the GTO was an option on the Lemans unless the GTO/389 option increased the sway bar diameter as part of the option. You just need to measure the OD to confirm.

1968-'69 went to 1.0 "

1970 went to 1 1/8"
 

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Discussion Starter #3
Ok. I’m looking to do my suspension and I see that there are ones that go to 1 1/4. Should I just go with the stock 15/16 or go with the larger diameter?
 

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Ok. I’m looking to do my suspension and I see that there are ones that go to 1 1/4. Should I just go with the stock 15/16 or go with the larger diameter?
If you want better turn in / performance - get the largest front sway bar possible. If you already have a sway bar, I doubt you'll feel the difference unless the rest of your suspension is dialed in.
 

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Ok. I’m looking to do my suspension and I see that there are ones that go to 1 1/4. Should I just go with the stock 15/16 or go with the larger diameter?
If you have the stock sized bar, I might first try a new stabilizer link kit and stabilizer attachment bushings using the polyurethane bushings. These are much stiffer than the factory type rubber bushings and will deflect less, thus in effect stiffening the suspension.

You may not gain much by going with a larger front bar by itself. You want to balance out the front with a rear stabilizer. If you go too large and stiffen up the front suspension, it can affect steering - under/over steering and now you have a dangerous condition if you are not ready for it.

As cij911 pointed out, you may not notice any big difference without balancing out the suspension as viewed as a complete upgrade - stiffer springs and adding a matching rear sway bar.

If me and you have no plans on swapping springs, I would first try the polyurethane replacement bushings to tighten things up. PST is one manufacturer that offers these as polygraphite which I feel is a little better than the polyurethane type due to the graphite. I used their body mount bushings. https://p-s-t.com/i-23159970-polygraphite-front-sway-bar-frame-bushings-15-16.html and https://p-s-t.com/series-220376-polygraphite-front-end-links.html#!year=1965||make=PONTIAC||model=GTO||submodel=BASE

I have also used the less expensive Prothane polyurethane bushings which are currently used on my '68 Lemans build having the larger front sway bar. PST at the time did not offer the polygraphite parts for the front sway bar. https://www.summitracing.com/parts/ptp-19-1133-bl and https://www.summitracing.com/search/product-line/prothane-sway-bar-end-link-sets/year/1965/make/pontiac/model/gto

If that works, next add a rear sway bar. You could use the factory 7/8" rear size bar. Keep in mind that the later GTO's got heavier, and the bar diameter is matched to the weight as well. The '65 body is a bit lighter so going with the later heavier bars or the big one offered by aftermarket companies may not be what you want as it could be too stiff.

Below are two options for sway bars. You would have to drill your own holes in your lower control arms, but not too difficult. I would get the "shims" for the sway bar and this I assume would give you the correct bolt hole spacing for either.

https://www.opgi.com/gto/ADDC938/?gclid=EAIaIQobChMIpIDIib3h4QIVyFcNCh2g7gJ9EAQYASABEgIe7_D_BwE It appears that you can get the bolts/nuts/inserts for use with your factory control arms. Not sure if it is part of the purchase or you need a separate kit.

Here is a 1" diameter which will also work. You may need bolts and nuts and if it did not have them, make some tubular spacers that go inside your factory control arm so you do not overtighten and crush them. You can read the reviews. https://www.summitracing.com/parts/opg-addc939/overview/year/1965/make/pontiac/model/gto

If you do not feel comfortable, or don't want to drill your lower control arms, you can purchase them new with the holes drilled and "boxed," and new control arm bushings. https://www.opgi.com/gto/KR0445P/ You may or may not need a shim kit with these if your sway bar fits tight within the lower control arms, so I would wait until I installed them before assuming I needed then and did not - just saves a few bucks.

Just a few things to consider and look into. :thumbsup:
 

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Discussion Starter #6
Thanks for all the info guys. I have one more question. Are the front spindles for disc and drum brakes the same? I can’t seem to find anywhere that sells ones for drum brakes. I’m looking for standard height. Everything is either a drop spindle for disc or standard for disc.
 

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Thanks for all the info guys. I have one more question. Are the front spindles for disc and drum brakes the same? I can’t seem to find anywhere that sells ones for drum brakes. I’m looking for standard height. Everything is either a drop spindle for disc or standard for disc.
Yes, unless you want to upgrade to something like the corvette c5 spindle / hub.

IMHO, I would think long and hard about what you want from your car (suspension wise) before proceeding. Given the sway bar question and now spindle question, you may want to think about big brakes. In my humble opinion, my big brake upgrade and suspension upgrades completely changed the car for the better. My car while powerful, was always limited by the suspension and brakes, but that is no longer the problem. Now I want more power.....
 
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