Re: Beginner Suspension Upgrades
[Re: kzinge1]
#1193472
03/30/12 10:40 AM
03/30/12 10:40 AM
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Joined: Jan 2003
Posts: 5,405 Pikes Peak Country
TC@HP2
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master
Joined: Jan 2003
Posts: 5,405
Pikes Peak Country
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Go back up a bit and re-read my original post. I suggest shocks as the second mod right behind the sway bar for the simple fact that even with light spring rates, greater shock control yields the highest dividends on a typically taller, street oriented car. If you need to break it up, buy the fronts first, then the backs. Yes,they are pricy but shocks are to the suspension system what a camshaft is to an engine. They control all the operating parameters such as usable range, response, feel, etc.
What the Bilsteins will do is take all the harshness out of the straight, level road cruising. All those little bumps and ripples you would normally feel in the road will be smoothed out, but when you throw it into a corner at speed, they will better control the motion without allowing the car to wallow, yet still be able to absorb those small irregularities. This is why good shocks are able to control low speed circuits and high speed circuits without compromising the action of either or having to pump up their performance with large nitrogen charges.
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Re: Beginner Suspension Upgrades *UPDATE-SWAYBAR INSTALLED
[Re: kzinge1]
#1193474
04/01/12 11:56 PM
04/01/12 11:56 PM
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Joined: Feb 2010
Posts: 1,645 Phila. Pa.
Mattax
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Phila. Pa.
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I think it really depends on the combo. Not sure about B bodies, but the A body SS springs came in 3 varieties IIRC (maybe 4 including the orignal Hemi SS Springs). Each flavor was the same rate but different initial arch. IIRC the 002/003 were for light cars and had the least arch.
If both springs are the same, and you think the rear is too high, then an option to investigate is dearching. Pretty sure thats what they did for the Green Brick. Beckman's Rallycuda also uses SS springs, but they carry a lot of weight on the rear and do not want the car lower than stock so they are not dearched.
Another option, possibly in conjuntion with the dearching, is a slightly higher spring eye mount (aka adjustable hanger). You'll have to measure and experiment a bit because these things effect wheel hop and spring windup as well.
If you're going to change springs, then best is to find out how much weight is on the rear wheels. Then you can come close to the height you want by calculating the free arch for a given spring rate.
Definately address the pinion angle. Front and rear u-joint angles should cancel each other out. A little nose down on the diff compensates for when it torques upward. Standing start launches usually being the worst case and so need most compensation. Speedway Motors carries 2.5" wide pinion angle wedges, or did.
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Re: Beginner Suspension Upgrades *UPDATE-SWAYBAR INSTALLED
[Re: kzinge1]
#1193477
04/02/12 11:03 PM
04/02/12 11:03 PM
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Joined: Dec 2004
Posts: 802 central CT
cudazappa
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Right now you're doing a lot of parts changing at once. Obviously you've come to the conclusion that your 318 bars will be too soft as compared to the rest of the suspension. I've been hearing mixed reviews about the 1.03" bars (namely PST has the clocking off?) so you may want to look into another brand/source.
From my experience, you're in the ballpark with 1.03" torsion bars. I'm using a Just Suspension 1" t-bars on my Challenger. They were too stiff with stock leaf springs and no rear bar, but now that I have a rear sway bar, I now need to upgrade my front torsion bars (about 1.03" would match right now with my stock leaf springs).
If you can, see if you can find a source for the 1" bars, or maybe somebody is offloading their 1"+ bars cheap. You're changing a lot all at once so you may want to get a feel for the car before you finish dialing it in.
1971 Challenger
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Re: Beginner Suspension Upgrades *UPDATE-SWAYBAR INSTALLED
[Re: Mattax]
#1193480
04/03/12 12:10 AM
04/03/12 12:10 AM
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Joined: Dec 2007
Posts: 284 Louisiana
kzinge1
OP
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OP
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Quote:
Leave the rear sway car off until the front springs are increased. Please reread my third post (#7110921 - Fri Mar 09 2012 02:51 PM ) in this thread about oversteer, and you can go to this thread for several good posts about oversteer and rear sway bar choices.
Matt, Thanks again for your comments, you have been vey helpful so far. I read through the link and your earlier post. The reason I went ahead and ordered the rear sway bar is because I am going to change out the t-bars. Now I just need to know exactly how stiff I should go with them. Will 1" be stiff enough to support a rear bar? Or should I go bigger? I can leave the rear bar off altogether, but from why I've read so far, a rear bar should be helpful with 1" or larger t-bars. Am I on the right track here?
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Re: Beginner Suspension Upgrades *UPDATE-SWAYBAR INSTALLED
[Re: kzinge1]
#1193481
04/03/12 12:27 AM
04/03/12 12:27 AM
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Joined: Jan 2007
Posts: 7,664 IN
ahy
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IN
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Quote:
Yeah, I am pretty much changing all the major suspension components, that's why I've been asking so many questions and everyone has helped a lot. I pretty much knew nothing about suspension when I started this thread, I feel like I have a good idea of what I need now.
I was kinda unsure about the PST bars, because they have a warning on their website about them only being for lowered cars and you can't return the car to stock ride height after install. I was going to call and ask them about that before I ordered. I may have to get the ones from Just Suspension but I was really wanting something a little stiffer. I may go with a set from Firm Feel, seems like they know what they are doing and they have a better selection. The price reflects that though
That "warning" doesn't sound right or necessary. No reason you cannot have full adjustability... especially with the stiffer bars. I agree 1.00" or 1.03" is in the ballpark but maybe you need to find another source for the bars.
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Re: Beginner Suspension Upgrades *UPDATE-SWAYBAR INSTALLED
[Re: kzinge1]
#1193483
04/03/12 09:53 AM
04/03/12 09:53 AM
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Joined: Feb 2010
Posts: 1,645 Phila. Pa.
Mattax
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Phila. Pa.
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Quote:
I can leave the rear bar off altogether, but from why I've read so far, a rear bar should be helpful with 1" or larger t-bars. Am I on the right track here?
Not sure where you got the idea that t-bar size equates to rear sway bar, but that's not really right. In fact, skimming through the posts FrankenD specifically wrote ".. with a custom 1 1/4" front sway bar, 1" torsion bars and KYB shocks in front with Mopar Performance leafs, 7/8" rear sway bar and KYB shocks. My Charger kicked the tail out too easily and felt too squirrelly, so I pulled the rear sway bar off. It rolls and leans a little more, but it also handles predictably."
Whether a rear bar can be or should be used is about the total package starting with weight distribution; then spring rates and roll rate distribution, cg, roll centers, tires and use. Paraphrasing a comment in that other thread; the sway bars, especially the rear sway, are best used as a tuning tool.
Since we don't know the weight distrubution, nor the rear spring rates, nevermind the more subtle stuff, theres no way for us to know if this, or any rear bar will be too much. If your car is anything close to Frankendusters, then there is a good chance this rear bar could create too much rear roll rate.
As Rick E-berg was pointing out in the other thread, oversteering setup can sneak up on you at higher speeds. On the street, downhill curves create a situation where rear traction can get reduced sufficiently to put even a normally neutral car into oversteer. Combine this with wet or other surface conditions and things get even more dicey. Believe me, this is not so fun to learn the hard way.
Last edited by Mattax; 04/03/12 10:03 AM.
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Re: Beginner Suspension Upgrades *UPDATE-SWAYBAR INSTALLED
[Re: Mattax]
#1193484
04/03/12 12:07 PM
04/03/12 12:07 PM
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Joined: Jan 2007
Posts: 780 Woodinville, WA
Viol8r
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super stock
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Woodinville, WA
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Reading your OP and looking over your initial set-up there is really no reason to rush to put a rear bar on this car. Your overall combination, i.e., tires combo, Comp Eng shocks, lack of tubualr uppers??, etc. etc. will hold you back from doing anything requiring the fine tuning of a rear bar.
Work on the front of the car first, and when you decide to take the next step with shocks/ tires and correct rear springs then I would think you consider a rear bar.
We run a rear bar on a Big block car, but we also run 26 way adjustable shocks, 1.12 front bars, 1 3/8 Hotchkis sway bar. This combination still has a moderate amount of oversteer, but I like it.
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Re: Beginner Suspension Upgrades *UPDATE-SWAYBAR INSTALLED
[Re: kzinge1]
#1193485
04/03/12 12:15 PM
04/03/12 12:15 PM
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Joined: Jan 2007
Posts: 780 Woodinville, WA
Viol8r
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super stock
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Woodinville, WA
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Quote:
Alright, I have the 1 1/8 sway bar installed up front, and I have the xHD leaf springs, RCD Bilsteins, and 7/8 rear bar all on order. Next up is the torsion bars. I was thinking the 1.03 bars from PST. What do you guys think?
This is not enough front sway bar and front torsion bar to justify a 7/8 rear bar. I would consider staying away from the rear bar for now IMHO.
I would have really liked to have seen you go to an 1¼" bar. Oh well, I been down that road. Big block cars need a lot of help up front to control the roll. As you can see, we run a pretty agressive set-up and its still could you use some more!
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