Author Topic: torsion bar sizes  (Read 4994 times)

Offline dodj

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Re: torsion bar sizes
« Reply #15 on: April 27, 2016 - 03:53:45 PM »
I think you will be pleased with the difference.
Scott
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2007.5 3500 6.7 Cummins Diesel, Anarchy tuned.
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Offline crash340

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Re: torsion bar sizes
« Reply #16 on: April 27, 2016 - 10:56:07 PM »
I went from .9, to FF's 1.06, go bigger, much bigger, I barely noticed any change, in fact I couldn't!. I might be selling the 1.06 if I can and I'll go bigger, 1.18 at least, and I have a SBM
Greg

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Offline HP2

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Re: torsion bar sizes
« Reply #17 on: April 28, 2016 - 09:56:41 AM »
I'd still recommend a call to Bill Reilly since you have his aftermarket rear suspension already. I agree that a 1.12 bar is probably you best bet, but you also want to maintain balance of the system and that may mean an adjustment to the rear as well, unless your car was severely oversprung in the rear previously.

Offline Road_Runner

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Re: torsion bar sizes
« Reply #18 on: May 18, 2016 - 10:10:17 PM »
I've tried many different TBs... car was progressively built for SCCa pylon AX...  I settled with the largest size of 1.24" (hex opening is 1.25")... these TBs rated at 425 # per inch (from a past Mopar compony called California Moparts/Suspension  i the 80s... they later went out-of-business... too bad, ahead of their times.

I've offered mu opinions from past experience - don't be afraid of larger TBs.   Even at my current 1.24", they're not as stiff as you may think.  sure, the ride is stiffer, but its completely still driveable for the street/hwy... as long as you don't routinely drive over pot holes and rough train track crossings (just slow down then or avoid that drive as much as possible... no fun!).

As HP2 has similarly said, with soft TBs your car has more of a tendency to bottom out, and the lift/lean will prevail.

Consider nothing less that ~1.12 for a SB car... or even 1.18 for a BB car... you won't regret it and only wonder WHY you didn't install these larger TBs earlier.  Call Firm Feel as they readily have the 1.12 and 1.18 in-stock... and they'll gladly make you larger (up to 1.24).

ALSO, consider spending good $$ on good shocks... you pay for what you get.   I recommend double adjustables (Viking, QA1, Starnge, others)... the Vikings are probably the best buy as they originated from the QA1 designs (same past people), and Viking ONLY makes 2x shocks to keep their costs down.

AND... consider stiffening your rear leafs a little... too stiff an you'll really feel it... current "handling" leafs (from various vendors) are all pretty good.

I suggest to use the sway bar sizes as a fine-tuner in the handling... your choices prevail.

Hi again,

You've offered me advice in the past and I'm once again considering making the Barracuda into an autocross & occasional track day capable street car.  That said, here's what I've bought so far but not installed: .96 Mopar Torsion Bars, 1 1/8 Hellwig hollow front sway bar, original 3/4 rear bar.  ESPO rear XHD leaf springs, Edelbork IAS shocks and weld in US Tools frame connectors.  Sounds like you'd definitely suggest much larger torsion bars, how do you think the rest of the parts will work together?  Anything glaringly wrong for my intended purpose, best bang for my buck change?  Wheels and tires are BFG's on 15x7 & 15x8 rallye wheels, but that could change especially the rubber.  Any suggestions would be greatly appreciated!

Later, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black

Offline Mopar Mitch

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Re: torsion bar sizes
« Reply #19 on: May 19, 2016 - 01:33:07 AM »
Jim -- your intentions are good. Your setup will be different so you'll have to learn to adjust.  Seat/track time will help you make better judgments.... I've been there and offer my suggestions.    ABSOLUTELY get larger TBS... 1.12 TBs are a good "compromise"...   don't hesitate on them... and you WILL then wonder why you're not going stiffer, such as 1.18  or eventually larger pending how serious you want to be, and competitive, with the AX/track days.   Rims/tires will have to become larger... the YearOne 17x9 are excellent fit front and rear.. 275-45-17 tires... search for 200 treadwear tires (pickings are few in 17s as 18s offer wide choices of 200 TW).  A better driver's seat and harness will be needed , as well as a smaller diamter steering wheel (TUFF wheel at minimum).
Autocross/road racers go in deeper... and come out harder!

See  MOPAR ACTION MAGAZINE, AUGUST 2006 ISSUE for featured article and details on my autocross T/A.

Offline Road_Runner

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Re: torsion bar sizes
« Reply #20 on: May 19, 2016 - 09:22:34 AM »
Jim -- your intentions are good. Your setup will be different so you'll have to learn to adjust.  Seat/track time will help you make better judgments.... I've been there and offer my suggestions.    ABSOLUTELY get larger TBS... 1.12 TBs are a good "compromise"...   don't hesitate on them... and you WILL then wonder why you're not going stiffer, such as 1.18  or eventually larger pending how serious you want to be, and competitive, with the AX/track days.   Rims/tires will have to become larger... the YearOne 17x9 are excellent fit front and rear.. 275-45-17 tires... search for 200 treadwear tires (pickings are few in 17s as 18s offer wide choices of 200 TW).  A better driver's seat and harness will be needed , as well as a smaller diamter steering wheel (TUFF wheel at minimum).

I actually have a tuff wheel to put on but didn't consider how it's really part of a better track set up!  Since you're running on track days, are you running a roll bar?  If so, is it a 4 point, 6 point?  I know it probably isn't required, especially for autocross, but it could come in handy on the track.  Thanks again, Jim 
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black

Offline Mopar Mitch

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Re: torsion bar sizes
« Reply #21 on: May 19, 2016 - 05:44:46 PM »
Jim -- The factory TUFF wheel is a little slippery IMO, and there are better replicas offered with better grip (and at 14" diameter instead of the Grant 15" TUFF wheel)... its a simple bolt-on/swap... although.. I have chosen and tried/favor smaller 11.5" thick/padded diameter for quicker steering action (make sure you use a SAGINAW only power steering pump!... the FEderal pumps cannot keep up with quick LRLRL actions, worse at higher rpms which you'll do during pylon AX).

I've never (yet) installed a roll bar (not "required" by rules in my SCCA AX E/SP or other club's HSAX classes... I'm considering an eventual 4-6 pt roll bar ... or else a removable cross bar... just for the harness (currently mounted straight down behind the seat... not ideal/safest).  Eventual SFCs to be added (past SCCA rules didn't allow welding... later changed ~early 2000s... then I took a break/hiatus from the SCCA AX.... now back since 2010 doing HSAX with a different group/club for track days/HSAX/HPDE... goal is competition HSAX series with the www.mcscc.org  ... my car is in rebuilding/restification stage now until ~2017.   FUN and good social events!... including W2W Pace Car occasions! 

Despite not having a roll bar or SFCs, the car is very stiff with the 1.24 TBs, stiff leafs, Koni shocks, 1.25" f/1.0" rear sway bars, etc.... and well-sorted over the years of AX and more recently HSAX track days... and very streetable (highways preferred.... avoid "street" bumpy roads, etc).

You should determine a club's set of "rules" for the class you'd prefer to run in.. study those rules/classes... and build/modify accordingly...  less mods=less overall expenses.. and possibly better competitive results.. higher-mod classes=higher expenses/tougher competition... active drivers probably have more track/experience time and sorted out their car better vs a newbie... but again, time behind the wheel doing the AX/track days will be your most desired goal for improvement.... the "nut behind the wheel". 
Autocross/road racers go in deeper... and come out harder!

See  MOPAR ACTION MAGAZINE, AUGUST 2006 ISSUE for featured article and details on my autocross T/A.

Offline Chryco Psycho

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Re: torsion bar sizes
« Reply #22 on: May 19, 2016 - 10:42:35 PM »
I had a really weird experience , years ago  i installed a set of 1.22 bars in a GTX , it was rediculous , I could not set the ride height as even with the adjuster screws backed right out it was sqeezing the rubber up stop so the bars were phased wrong but even at that I was able to just barely install them there was zero give in the bars , you could jump on the front end & all that would give was the tire sidewall  we took it for a drive looking like an old gasser & it was like having solid suspension ,, I have no lue why they were so still so I have since shyed away from max diameter bars !

Challenger - You`ll wish You Hadn`t

Offline Mopar Mitch

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Re: torsion bar sizes
« Reply #23 on: May 20, 2016 - 04:12:15 PM »
Chryco -- something wasn't right... fully loosened TBs and LCA pin?... raising/aligning the LCAs to install the TBs/hex as needed?   Who was the vendor/supplier of those TBs?  Sounds to me that you may have had the LCAs fully down when instead they should've been raised during the installation for proper alignment (I've done it a bunch of times with different sizes, as well as with my great 1.24"TBs).
Autocross/road racers go in deeper... and come out harder!

See  MOPAR ACTION MAGAZINE, AUGUST 2006 ISSUE for featured article and details on my autocross T/A.

Offline Chryco Psycho

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Re: torsion bar sizes
« Reply #24 on: May 20, 2016 - 07:26:33 PM »
Yeah I never figured it out

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Offline EB3-GranCoupe

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Re: torsion bar sizes
« Reply #25 on: May 20, 2016 - 08:28:15 PM »
 :popcorn: