Torsion bar

[q8charger]

Hello ,

My 1969 charger  original engine  was 318 and right  now some one change the engine to  440 . Should I change the Torsion bar 

Thanks

[krops cars]

I would. I got mine from PST.

[303 Mopar]

Yes - bigger is better.  I would look at PST or Hotchkis.

[q8charger]

Thanks, so the bigger is better . The PST 1.03" Torsion Bar and Hotchkis is 1.100''

So Hotchkis is better right?

[Brass]

Firm Feel also has a selection of bars.  My car has an RB and I switched from the stock 318 bars it was born with to 1.0" bars.  It was a big improvement for the street.  You might want stiffer bars if you spend time on the autocross.  Softer if it sees a lot of drag racing at the track.

[c00nhunterjoe]

Are the pst bars the ones that are clocked differently from stock and make the cars sit lower?

[q8charger]

Okay

Right now i find 1.18 DIA. Race App. (WR 338) and 1.12 DIA. Race App. (WR 270) from Firm Feel both .

[WhiteOnGreen]

Keep in mind stiffer torsion bar accentuates understeer if you don't make changes to the rear suspension

[Mike DC]

We say "bigger is better" because the factory torsion bar sizes were too light (for modern tires).  


Bigger is not better all the time.  It can be overdone.  That's true for any suspension spring, or shock/damper, or sway bar.    

Many guys are happy with torsion bars around 1.00" size.  I would suggest something in that area if you are building an all-purpose street cruiser.  If the car is still leaning more than you like in corners then I suggest increasing the sway bar sizes (use a bigger sway bar in front + add a small sway bar to the rear).

-------------------------

The stiffness of torsion bars (and sway bars) increases GREATLY as the diameter goes up.  I just pulled this chart off another Mopar forum.  You get the idea.  Look at how fast the lb/in numbers increase.  

0.810" 82 Lb/In SLANT 6/DRAG RACING
0.870" 109 Lb/In SMALL BLOCK V8/STREET/DRAG RACING
0.890" 120 Lb/In BIG BLOCK/STREET/DRAG RACING
0.920" 137 Lb/In PERFORMANCE STREET
0.990" 184 Lb/In PERFORMANCE STREET/SOLO/TRACK DAY
1.040" 224 Lb/In PERFORMANCE STREET/SOLO/TRACK DAY/ROAD RACING
1.090" 270 Lb/In SOLO/TRACK DAY/ROAD RACING/OVAL TRACK
1.120" 305 Lb/In SOLO/TRACK DAY/ROAD RACING/OVAL TRACK
1.140" 323 Lb/In SOLO/HD-ROAD RACING/OVAL TRACK
1.180" 380 Lb/In SOLO/HD-ROAD RACING/OVAL TRACK
1.200" 396 Lb/In HD-SOLO/HD-ROAD RACING/HD-OVAL TRACK
1.240" 452 Lb/In HD-SOLO/HD-ROAD RACING/HD-OVAL TRACK

The original 318 bars would be close to the 0.89" size of 120 lb/in.  The 1.03" bars would be around, what, maybe 210 lb/in?  That is nearly double the stiffness of your originals.      


By the way, I suggest you measure the bars in the car before you assume what size they are.  After 50 years many cars have replaced torsion bars.  It's tricky because paint/coatings on the bars can be enough to affect the measurement.  But you don't want to put any deep nicks/scratches in the surface of the metal bars - that leads to cracks.  
         

[Kern Dog]

I run 1.15 bars in my car. I got them from Bergman Auto Craft. The car does NOT ride too stiff, it is about the same as our 1025 Challenger R/T.

[Mike DC]

  
Suit yourself.  Different personal preferences.  

But a bar around 1.00 is a popular size for B/E-body street cars.  I'm not the only one who likes it there.  


I'm not a fan of super-stiff wheel springs in general.  Not for the T-bars or the rear leafs.  The shocks (and sway bars) should be doing a lot of the work.  

[Kern Dog]

I had 1.0 bars and KYB shocks for 14 years and the car actually rides and handles better with these 1.15s and Bilsteins.

[Nacho-RT74]

Hello ,

My 1969 charger  original engine  was 318 and right  now some one change the engine to  440 . Should I change the Torsion bar 

Thanks

You can run somehow the SB T bar but will need to bolt it up to reach the ride height. Of course bigger bar will hold better the extra weight as factory made using 0.89 or so T bars for SB and 0.92 T bars for BB ( increased to 0.96 I think on 73 due the extra lenght ), so, yes, upgrade it so save the stress on original bar and the extra weight like factory made.

You don't need to go bigger than that if using the car under normal circunstances or driving conditions.And in fact, I wouldn't go bigger than 1" if wanna go still bigger than factory. You will notice as bigger difference every turn of the adjusting bolt will raise more the front on those bars being thicker bars. I'm using a FF 1.06 T bar and honestly 1" could be enough for me. The stiffening if whished on suspension will be performanced better using the right shocks accomplished with the new bars

[krops cars]

c00nhunterjoe  The PST ones I have are not clocked different. They may have an option for lowering them that I do not know of.

[Nacho-RT74]

I know there is some brand making those with ouphased hex ends

[375instroke]

Some sources suggest shooting for a wheel rate of 10% of the vehicle weight on that end of the car.  These cars are around 59%/41% weight distribution, so with a 4,000# car, that's 2,360# front, 1,640# rear.  The 1.04" bars are what I use, which come a little under the 10% suggestion, and the stock Hemi leafs are 140#, which are a little under, too.  A 1-1/8" front sway bar, along with QA1 single adjustable shocks rounds out what I have so far.  BFGoodrich tires are what I have, but even with those crappy tires, my Charger handles better than I could have imagined.  I car if perfectly neutral as fast as I have dared drive it.

[303 Mopar]

I have 1.06 and Bilstein shocks from PST on my Charger and 1.10 and Fox shocks from Hotchkis on my Cuda. Both handle very well and were a big improvement over stock.