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Re: Sway Bars

Posted: Sun Mar 15, 2015 4:44 pm
by Navy Lifer
nothing specific on "rates", per se.

As I mentioned in the other active thread I just replied to, the wire diameter and number of free coils indicate the SS springs will be "softer", but I do not know what impact this has on load-carrying capacity. Beyond my level of knowledge to calculate, but I know there are formulas to do that.

If I could get the springs on a rate-checker as often used by oval racers, it would be interesting to see what the numbers are....I'll work on that.

The SS measured suspension height IS lower than PPV--lighter car on softer springs. The SS is lighter, by maybe 200-250# compared to PPV, so with a known lower static suspension height vs stock PPV, and the greater weight of the PPV, the ride height (with equal wheels/tires) SHOULD mean the PPV will sit slightly lower than SS (or, in reality, the SS springs used on a PPV will be slightly more compressed).

Shocks for PPV should be fine--they are actually valved heavier than the 2014 SS shocks, as part of the package for the type of duty, as well as the heavier (stiffer) springs used on PPV. Bigger springs (wire diameter) means more energy to control, so the shocks are valved appropriately to do the job. Even with the heavier valving of the OE PPV shocks, I don't think it will be too harsh with the lighter SS springs. That is where I think the change of sway bars will complement the entire package--springs/shocks, wheel/tire choice.

Depending on your car's model year and VIN, there was a running change for rear shocks mid-2011, and 2012 brought new front shocks that are reported to be a significant improvement over 2011 front shocks--I got this information from a GM engineer I know that was able to reach someone in the PPV program for some suggestions. My car has the 2nd version rear shocks already, and I have a pair of the new front shocks that will be used when I do the SS spring swap.

I am also going to a 19" wheel with 255/40 tires all around, so I'm cognizant of what impact tire sidewall can have on NVH & ride quality vs the stock tire with 50 aspect ratio...another reason to go with an OE spring combination rather than aftermarket lowering springs.

Re: Sway Bars

Posted: Sun Mar 15, 2015 6:36 pm
by CrashTestDummy
Any clue where that weight reduction is coming from? Lower weight is a win all the way around.

Re: Sway Bars

Posted: Sun Mar 15, 2015 6:56 pm
by xcidmigs
2014 SS sedan:
Exterior Dimensions
Wheelbase (in / mm): 114.8 / 3916
Overall length (in / mm): 195.5 / 4966
Overall width (in / mm): 74.7 / 1897
Overall height (in / mm): 57.9 / 1470
Track (in / mm): front: 62.6 / 1590
rear: 62.4 / 1585
Curb weight (lb / kg): 3975 / 1803

2015 caprice ppv:
EXTERIOR (in./mm)
Wheelbase 118.5/3010.0
Overall length 204.2/5187.0
Overall width (excluding mirrors) 74.8/1898.7
Overall height* 58.7/1490.0
Front track width 62.8/1596.0
Rear track width 63.2/1606.0
Curb Weight V6/V8 4043/1834 4162/1888

All that info is from GM webpages looks like its the extra wheelbase and overall length that get you... SS sedan also has some aluminum body panels not sure about PPV

Re: Sway Bars

Posted: Sun Mar 15, 2015 7:36 pm
by Navy Lifer
Gene, what you really need to do is find the weight of VE/G8 GXP (w/heavy front brakes) and compare it to SS sedan--just remember that SS is a fully loaded car compared to PPV. The total weight reduction for the SWB (VE/G8 vs VF/SS) cars is in the 150# range. There are no aluminum body panels on PPV. Some suspension parts for both SS and 2014> (WN) Caprice PPV are now aluminum, so there was SOME weight reduction compared to 2011-2013 (WM) Caprice. VF (SS) and WN (PPV) also now use some high-strength steel in certain areas that is also lighter. so there are some trade-offs on weight even between WM & WN (LWB) models, such as fatter sway bars on the 2014 & newer PPV. Dual battery option in WM PPV added more weight--not sure if it's still offered for WN, but probably so...that adds to the "curb weight"--my 2011 PPV does have it, and I suspect most PPV's do, but it was not standard.

The longer wheelbase of PPV means a little more sheetmetal, a little more glass, and a longer driveshaft, mostly, so I can't really say what that might add to total weight, but I would think it's going to be in the 50# or less range, honestly. Slightly heavier springs, and very heavy steel wheels (32# each) vs 24#/25# for SS also come into play--and a heavy standard full size spare on PPV vs optional on SS (air pump standard).

Re: Sway Bars

Posted: Mon Mar 16, 2015 11:34 am
by CrashTestDummy
I had no idea the PPV was longer. That must by why they seem to look a bit nicer (to me) than the SS, although I couldn't tell you why. I guess I was hoping for some lighter body panels/suspension bits, as I would have figured an-up-fitted PPV, with fewer options, would actually weigh less than an SS. Longer wheelbase will definitely make a difference, as would the wheels. Not sure what I'm going to do with the wheels, yet. I don't know if the PPV we're getting has dual batteries or not, our Tahoe didn't. If we're sporting dual batteries, a couple of Brailes can fix part of that issue. I'll definitely be swapping them out if they're still liquid acid batteries.

Re: Sway Bars

Posted: Mon Mar 16, 2015 12:24 pm
by leadfart
Gene,

The PPV is a much bigger car than the G8 or SS. One of the biggest volume wise rear drive vehicles out there. They just don't look that big, because of the narrower body. 8-)

Re: Sway Bars

Posted: Mon Mar 16, 2015 2:35 pm
by CrashTestDummy
IIRC it's a little shorter than a 94-96 B-body, too. That's nice, as the Tahoe PPV is a little wider than the 9C1 it replaced. It's garage-mate will provide some dancing room in the garage. ;)

Re: Sway Bars

Posted: Tue Mar 17, 2015 2:04 pm
by Pursuit
After getting my butt kicked with the front sway bar, I did some quick research and found that I wasn't the only one to have issues. (G8 or Camaro). Lifting the engine is mentioned in some threads, looseing the power steering hose is also. Others have removed the tie rod ends and radius arms from the both steering knuckles. Almost all installed the bushings and brackets after the sway bar was in place. There are also threads where the swap wasn't a big deal. I also found the BMR install instructions for a G8.

https://www.bmrsuspension.com/siteart/i ... nstall.pdf" onclick="window.open(this.href);return false;
https://www.bmrsuspension.com/siteart/i ... nstall.pdf" onclick="window.open(this.href);return false;

I even found some people that just cut the original bar in half. Adding the bigger GM 2014 bar and the SB013 BMR set on the 1st hole (which creates the longest lever arm and the first level of stiffness) was a very worthwhile addition to the car. Bill Harper (Navy Lifer)has a very good understanding of the effects of swaybars, springrates, ride heights etc. He is willing to spend the time to do the research and test fit many different combinations. My thanks to him! The links to his information are a great resource and helped me to settle on what I did.

Regards,

Maurice

Re: Sway Bars

Posted: Sat Mar 28, 2015 10:43 am
by Navy Lifer
front bar install video

SuperPro video
https://www.youtube.com/watch?v=KHr093k2aVE" onclick="window.open(this.href);return false;

Re: Sway Bars

Posted: Sun Mar 29, 2015 7:23 pm
by xcidmigs
part #s for the 2015 SS springs yet?