Re: A-body Torsion Bars, How Big is Too Big?
[Re: joes68340s]
#2039000
03/26/16 04:23 AM
03/26/16 04:23 AM
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Joined: Dec 2010
Posts: 12,375 SoCal
MuuMuu101
I got lucky at Woodward!
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I got lucky at Woodward!
Joined: Dec 2010
Posts: 12,375
SoCal
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One thing that has me troubled is once you through in the 1.24 bars the front is going to be pretty stiff but the rear spring rates are going to be really soft. Even the Hotchkis springs at 130 are not going to cut it. That's what is holding me back from the change over. Get some custom ones made. I believe prrc got some composite springs made for his '65 Dart. Mopar Mitch has done the same for his ride. I believe ESPO or other companies will make whatever you want. Heck, a shop that works on trucks should be able to do it.
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: lawndart]
#2039001
03/26/16 04:25 AM
03/26/16 04:25 AM
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Joined: Dec 2010
Posts: 12,375 SoCal
MuuMuu101
I got lucky at Woodward!
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I got lucky at Woodward!
Joined: Dec 2010
Posts: 12,375
SoCal
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As for headers, TTI or Dougs generally fit the best. Wonder why the Doug's longtubes only go up to '72 for Darts per their site, mine's a '73? Do the TTIs or DOugs tuck up into the subframe rails better? I'm thinking about ditching longtubes because all of the (admittedly cheaper) ones I've seen on low a-bodies and b-bodies hang low enough below the subframe to where they scrape pavement pretty easily TTI and Doug don't hang as low as the Hooker and other brands as far as I know. TTI also offers a short tube header and I believe that is the best fitting header on the market. The only person I know who had scraping problems with TTI's was autoxcuda, but that was because his Barracuda had 24" tires on them and the T-bars cranked down a tad.
Last edited by MuuMuu101; 03/26/16 04:34 PM.
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: Kern Dog]
#2039005
03/26/16 05:05 AM
03/26/16 05:05 AM
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Joined: Jan 2016
Posts: 16 SF Bay Area
lawndart
OP
member
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OP
member
Joined: Jan 2016
Posts: 16
SF Bay Area
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A few thoughts: The Magnum Force dropped spindles give a 2" drop. Headers with dents in them don't necessarily cost much in power. Hot Rod TV did a dyno test proving this very thing. The 73-76 A body header fitment differs from the 67-72 because of the intrusive motor mount design of the 73-76 models. The bigger the Torsion bar, the more critical chassis stiffness is. If the unibody flexes with .83 torsion bars, it will be worse with 1.24s. You also will never get the full advantage/stiffness since the flimsy chassis won't allow it. Subframe connectors, torque boxes, a welded K member, reinforced lower radiator support. etc are highly suggested. I think I'm gonna see how things go without drop spindles to start, just uncrank the adjusters and see where I'm at. Have all of those chassis reinforcement upgrades planned, but I think I'm going to do them after the cage. Thanks for the info on the 73+ motor mount header clearance difference
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: lawndart]
#2039079
03/26/16 11:52 AM
03/26/16 11:52 AM
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Joined: Nov 2006
Posts: 1,074 Manitoba Canada
67autocross
super stock
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super stock
Joined: Nov 2006
Posts: 1,074
Manitoba Canada
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I would go with the shorty headers, my full length TTI's are about 4 inches off the floor to the flange at the back of the collector, and they also touch the torsion bars.
A new iron curtain drawn across the 49th parallel
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: joes68340s]
#2039136
03/26/16 01:32 PM
03/26/16 01:32 PM
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Joined: Dec 2003
Posts: 23,299 Here
jcc
If you can't dazzle em with diamonds..
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If you can't dazzle em with diamonds..
Joined: Dec 2003
Posts: 23,299
Here
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I'm not a fan of the 2 inch drop spindle its a shame no one makes a 1 inch drop. at least affordable.
" All sorts of things can happen when you are open to new Ideas" Inventor of Kevlar
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: lawndart]
#2039148
03/26/16 01:49 PM
03/26/16 01:49 PM
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Joined: Jan 2003
Posts: 5,405 Pikes Peak Country
TC@HP2
master
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master
Joined: Jan 2003
Posts: 5,405
Pikes Peak Country
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IMO, you cannot overspring the front end of a t-bar mopar for competition purposes. This is a shortcoming of mopars that leaves us with increasing sway bar sizes to raise front roll couple percentages to level others makes can achieve with just springs. The best we can get for wheel rates is the 1.24 bars for any body style. You could perhaps go bigger if you adapted C body hexes to A,B, or E bodies and had Mr Ross and company make a custom set, but that's about it. However, this is certainly class and venue specific and your mileage may vary.
As a result of the limited choice of t-bar selections, I've always been an advocate of set up the front, then backing into the required rear rates. You can always create your own leaf packs with a little effort. Its not terribly difficult, it explains how in the Mopar Chassis manual, but drilling centering holes in spring steel does suck. If you go with a set of true custom leafs, they will get spendy. There is a lot more tech in a set of leaf springs than many give them credit for and you'll have to come up with answers to questions you never thought of.
It goes without saying that uber high spring rates require chassis stiffening. You want to reduce the body as an active participant in teh suspension equation as much as possible.
There is a 1" drop spindle out there, but it requires extensive mods to work and they are hard to find. '73 C body spindles accomplish this, but they are far from a straight bolt on. They also are taller and modify roll centers too. Wouldn't recommend it unless you have machining capability or are good friends with one.
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: lawndart]
#2039165
03/26/16 02:33 PM
03/26/16 02:33 PM
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Joined: May 2007
Posts: 701 Northern California
lilcuda
super stock
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super stock
Joined: May 2007
Posts: 701
Northern California
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With big t-bars you should step up beyond the RCD's. Like the bilstein adjustable level. 72 Swinger did that jump with a noticeable difference IIRC. And maybe some others. Autoxcuda, have any more info or p/n's on the Bilstein adjustables you mentioned? Think I'm gonna go with Firmfeel 1.24s, talked to Dick there today and he says I should be able to get the car to ride on LCA bumpstops by uncranking TB adjusters. We'll see what happens when I get em. Also think I'll order up the Hotchkis adjustable strut rods and the p-s-t greasable LCA pivot shafts and bushings on Monday. The one thing about the 1.24" bars is that header clearance is almost nonexistent. I think the headers are touching the bars. Could be an issue if the paint rubs off and they rust?
lilcuda, which brand headers are you referring to when you say theres no clearance with 1.24 TBs? I'm about to swap in a less-crushed set of no-name longtubes for the very-crushed set of hedman longtubes on the car currently and I may just dent 'em a lil to clear the TB although I'll probably be going with a set of hedman shorties eventually. Never done a set of longtubes on an a-body, looks freakin tight, does that job require lifting the motor or disconnecting brake booster/master cylinder? I believe the Valiant has TTI headers. They do hang pretty low, but I have yet to scrape them on anything. I don't know how hard they are to install, because they were on the car when I bought it. BTW, I just checked out the bumpstops. I was right. There are none on the lower control arms. I measured from the frame to the top of the LCA and it is 1 1/4".
'67 is an abbreviation of 1967 67' is an abbreviation of 67 feet They are not interchangeable.
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: joes68340s]
#2039729
03/27/16 02:28 PM
03/27/16 02:28 PM
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Joined: Oct 2015
Posts: 107 so cal
alltime
member
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member
Joined: Oct 2015
Posts: 107
so cal
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Funny you should bring this up I have a set of Firm Feel 1.24 Bars but haven't used them yet. I don't know what will happen or how it will sit. The Bars I'm running know have the adjusters completely backed out. and it sits low. I'm running 18 inch wheels its set up for autox now but I will also be running some track days. By the way I have a pair of 17x10 Bullet wheels for sale. I'm in Redwood city. Helpful tip for TB purchase. Some terms used for indexing are: Flat to Flat, Point to Flat. When you are approaching 1.08 and above TB installation you will quickly realize that the car doesn't settle as much in the front when lowering the car off the jack stands and on to the ground because of the newly increased wheel rate. Luckily it becomes more predictable as to what indexing you need for your car. I have seen different cars, IE, A-body VS B-body have a different LCA to Trans cross member anchor relationship requiring different indexing. So before ordering the bigger bars check your cars indexing. Remove your TB's. With a floor jack under your k-frame place your car at the desired ride height. Note where your trans cross member anchor is indexed and where your LCA anchor is indexed with the adjuster in the middle of its range and the tab seated. Most likely it will be flat to flat, or point to flat. If not, make notes of the degree rotation needed to rotate the LCA anchor to make it one of the above index configurations and order accordingly. When all else fails and you already have big bars and your car wont set down where you want it, send them to Dick at Firm Feel and tell him what indexing you need and he will heat, twist, and re Rockwell them for your enjoyment. That's why I always buy from in the first place because his products are mostly made on site and knows mopar building and handling himself. Then get on down to Willow Springs and let me drive you car. Providing you don't have any chineese spindles or brake parts on it...LOL Are the Bullet Rims OEM and how much?
Last edited by alltime; 03/27/16 02:31 PM.
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: alltime]
#2039796
03/27/16 04:01 PM
03/27/16 04:01 PM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
Striving for excellence
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Striving for excellence
Joined: Feb 2010
Posts: 18,493
Granite Bay CA
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Thanks, Alltime. When I swapped the 440 in my Charger in 2002, I also went from the stock .88 torsion bars to Mopar Performance 1.0 bars. Where the old stock set had the LCA adjuster bolt flush with the bottom, they now hung down over 1 1/4" with the 1.0 bars. I still had 5/8 to 3/4" from the LCA bumpstop to the frame rail so it wasn't as if I was riding that low. When I installed the Bergman Auto Craft 1.15 bars about a year ago, I followed Peters suggestion on how to adjust them. Sorta funny, I've installed plenty over the years and thought I knew enough to get by but by following his guidance, the car sits the same height as before but the adjuster bolt sits flush against the bottom like stock. I love the feel of the car with the bigger bars. It feels solid and responsive. Less brake dive, faster transitional response too.
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: lawndart]
#2041223
03/29/16 03:22 PM
03/29/16 03:22 PM
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Joined: Jan 2010
Posts: 1,443 NW Chicago suburban area
Mopar Mitch
pro stock
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pro stock
Joined: Jan 2010
Posts: 1,443
NW Chicago suburban area
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LAWNDART -- I've tried multiple sizes of TBS... as well as making progressive changes to the rear leafs, etc.
I settled with the 1.24 TBs (then readily avlbl from a previous Mopar suspension company called California MoParts/Suspension--- they were way ahead of the market in the 1980s... unfortunately closed). The 1.24 is the largest physical size that fits into the 1.25: hex opening.
I've said many times to offer my suggestive help to those concerned with ride "stiffness"... using larger TBs... don't be afraid... even at ~1.12.. 1.15... 1.18... then... ~1.20-1.22-1.24... these are NOT that much stiffer than you mat think for street driving. IF you ride on bumpy pot-hole roads, and routinely cross RR tracks, etc, then consider small TB like 1.12 or less.
The larger TBs will, especially, help prevent lift and dive, as well; as lean... during extreme driving conditions (competition AX/HSAX/HPDE)... and.. if you have a heavy front end, such a with a BB engine, etc.
Contact FF and they'll make TBs larger than their advertised limit of 1.18... up to 1.24.
You'll say and only wonder why you didn't install larger TBs earlier on... such a the 1.18 or larger.
BUT... also remember to progressively stiffen the rear leafs... and get good quality shocks.
THEN... use the sway bar to "tune" your handling of the car.
Last edited by Mopar Mitch; 03/29/16 03:23 PM.
Mopar Mitch
"Road racers and autocrossers go in deeper and come out harder!"... and rain never stops us from having fun with our cars... in fact, it makes us better drivers!
Check out MOPAR ACTION MAGAZINE, August 2006 issue for feature article and specs on my autocross T/A!
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Re: A-body Torsion Bars, How Big is Too Big?
[Re: lawndart]
#2045878
04/04/16 12:39 AM
04/04/16 12:39 AM
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Joined: Feb 2011
Posts: 4,302 Nebraska
72Swinger
master
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master
Joined: Feb 2011
Posts: 4,302
Nebraska
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What are your plans for rear springs?
Mopar to the bone!!!
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