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A little torsion bar experience and advice needed.

Mocajava

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I am in the process of stripping a 69' Coronet and about to pull the k member and torsion bars. I measured and these are .890" for a 383 2 barrel car, 727 w AC. I am rebuilding the 383 at present and that will be what is in there for a while untill I get the desire/ cash to build the 440 block I have stored in the corner. Just trying to get her totally finished and drive her for a while with the 383.

I will be putting a 440 in here at sometime and wondered if there are general rules to dictate which bar size I should put in for the future 440 weight. According to what I have read, with present day technology it has been determined that the .890" was too light to start with and most recommend 1-2 sizes up. I just wondered if anyone has experience and a recommendation as to what I should be replacing these with? Thanks in advance for any responses I get.
 
Thanks Super-bee_ski, I appreciate you consolidating the info. I read through as many as I could find using the search engine PRIOR to starting this tread. The thoughts seem to run from one end of spectrum to the other. I saw some posting to re-use the same bar if there are no marks or damage to others saying"you don't know what abuse they may have already seen...replace them". One post used three sizes or more larger because that is what worked for their car and style of driving while others were just one or two sizes up. I will probably step up one size to a .920" or so and hope that it works well for me and I can still adjust to suit if I need to. I was just hoping to beat the trial and error aspect and that is why I was asking about specific usage for a vehicle replicating what I have.
 
The stock size bars are fine unless you are planning on going hard corning.
 
If you look on the back of the bars you should see 778 on the rear of one side, 779 on the other side. 383 2 Barrel with A/C have the Roadrunner bars, which are the above numbers. The next step OEM was 780 and 781, for 440 and hemi Cars. I believe they are .92. I have the above in my 383 car, they are a little more stiff then the 778/779, but the handling Improved.
 
Thanks Super-bee_ski, I appreciate you consolidating the info. I read through as many as I could find using the search engine PRIOR to starting this tread. The thoughts seem to run from one end of spectrum to the other. I saw some posting to re-use the same bar if there are no marks or damage to others saying"you don't know what abuse they may have already seen...replace them". One post used three sizes or more larger because that is what worked for their car and style of driving while others were just one or two sizes up. I will probably step up one size to a .920" or so and hope that it works well for me and I can still adjust to suit if I need to. I was just hoping to beat the trial and error aspect and that is why I was asking about specific usage for a vehicle replicating what I have.

Mocajava, the weight difference between a 383 and a 440 is not too big a factor sir. I did this exact upgrade a few years ago and just took the opportunity to put new boots on the bars and reinstalled them....left, right. I did get the tool to remove them, and inspected them for burrs and damage, but other than that you should be good. Here's some engine weights for reference :


Engine *****Weight
Chrysler 331 Hemi * ** * 700
Chrysler 300 Poly V8 * * * *691
Chrysler 354 Poly V8 * * 691 - 700
Chrysler 354 Hemi * ** * 720
Chrysler 392 Hemi * * ** 740
DeSoto 276-341 Poly V8 * * ** 675
DeSoto 276-291 Hemi * * ** 630
DeSoto 330-345 Hemi * ** * 670
Dodge 241-325 Poly V8 ** * * 645
Dodge 241-270 Hemi * * ** 580
Dodge 315-325 Hemi * ** * 610
Dodge Viper V10 * * ** 716
Dodge Viper V10 (1997) * ** * 648*
Dodge truck V10 * * 816 - 836
Mopar Slant Six * ** * 475
Mopar 277-301-318 Poly "A" V8 * * ** 600+ (estimate)
Mopar 273-318-340 "LA" V8 * * ** 525
Mopar 360 "LA"*** * * ** 550
Mopar 350-361-383-400 "B" V8 * ** * 620
Mopar 413-426W-440 "RB" V8 * ** * 670
Mopar Street Hemi * * ** 765
 
Extensively discussed in many threads, but as someone myself who has run the .088, .092, and 1.00 in my '68 Plymouth Satellite, both with small block 360 and big block 451, I highly recommend to use either the .096 or the 1.00 bars. The .092's are OK, but if you drop the nose at all you lose some spring support. If in doubt, go with the .096's. You won't be sorry. The 1.00's are great too, but the .096 with a big block and no other upgrades should be perfect. Call Dick at Firm Feel - they make some of the best bars, easy to deal with, correct hex end clocking.

Firm Feel. .096 - put 'em in and let us know how you like them!

- - - Updated - - -

And when you install those .096" bars, install the Firm Feel tuned Bilstein shocks on all 4 corners. These 2 upgrades alone will TRANSFORM your car.
 
Thank you gentlemen, the personal information given for actual use is exactly what I was looking for. I will report back when I get this modification done and running.
 
The guys that turn corners agree that with the hex size of 1.24, you cannot actually "over-spring" a torsion bar Mopar. I run 1.15s in my aluminum headed 440/493. Bilstein shocks and big anti sway bars. The car rides and handles very much like my 2015 Challenger R/T. It is firm but not harsh.
 

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Love the picture Kern Dog and thanks for the information and opinion. Just pulling the front end this coming week, built support posts with wheels and installed them already. I am having a bear of a time getting the K member bolts out. Using a 1/2 drive socket, breaker bar and cheater pipe. Backing her out a few threads, squirt with penetrant, run back in...gaining a few threads every time but sure testing old muscles! Wish there was a way to get the penetrant inside the frame rail. Had thought about drilling a hole to be able to squirt inside to loosen her up. Have any of you drilled a hole to have access like that....or any other way to get those bolts free?
 
Mopar Action magazine guy Rick Ehrenberg suggested exactly what you wrote. A hole just large enough to get that WD-40 nozzle/straw in there is a great idea. You can clean the hole and fill it with seam sealer and undercoating afterward if welding isn't an option. Sometimes, that captive nut inside breaks loose and the only fix is to cut a flap in the side to get to the nut!
Thanks for the kind words.
 
I drilled a 3/16 hole through frame at each of the bolt areas and squirted about half a can of penetrant. Waited about 4 hours, found my air drive and went to work. Worked it in and out a couple times plus squirts and OUT they came! I will tap out the holes as soon as I get thread count and size and will be looking for new bolts to replace these. I am sure they have a certain hardness and that shape is irregular so I wonder if anyone has a source for buying a set? Thank you for the help Professors!
 
A 440 block is around 15 lbs heavier than a 383 block and has a little bit heavier crank and depending on the rods, add a few lbs for the 6 packs and piston size. 50 lbs heavier is probably the maximum over a 383. An aluminum intake will bring you just about back to the weight of a 383 but if you think the car is floating too much with the 383 bars, install firmer shocks on it.
 
I drilled a 3/16 hole through frame at each of the bolt areas and squirted about half a can of penetrant. Waited about 4 hours, found my air drive and went to work. Worked it in and out a couple times plus squirts and OUT they came! I will tap out the holes as soon as I get thread count and size and will be looking for new bolts to replace these. I am sure they have a certain hardness and that shape is irregular so I wonder if anyone has a source for buying a set? Thank you for the help Professors!

When rebuilding the front end on the Coronet I upgraded to .96 bars from the stock .89's. The Doug's headers on the driver's side come within a whisker of the T-bar. I wonder if guys with larger bars have to massage their headers to make them fit.
Several vendors stock the original style bolts, here's one:

http://www.rogergibsonautorestoration.com/images/2015_catalog.pdf
 
I drilled a 3/16 hole through frame at each of the bolt areas and squirted about half a can of penetrant. Waited about 4 hours, found my air drive and went to work. Worked it in and out a couple times plus squirts and OUT they came! I will tap out the holes as soon as I get thread count and size and will be looking for new bolts to replace these. I am sure they have a certain hardness and that shape is irregular so I wonder if anyone has a source for buying a set? Thank you for the help Professors!
New bolts - http://www.rosevillemoparts.com/product_info.php/p/torsion-bar-adjuster-bolt/products_id/9199
 
I have 1.12 torsion bars in my 74 clonerunner, It is the size Dick recomended along with the other items in a stage 3 package from firm feel. My big block car handles better than I expected it would, what a difference! I am happy with the 1.12, for me I would not want to go smaller than that.
 
After reading as much as I can on this subject throughout the forum, I am wondering how much effect raising or lowering the ride stance has on the torsion bar support/ performance? I like the idea of dropping the nose an inch or so to get a better stance and thinking through the mechanics of how the torsion bars operate. It seems to me if you drop the nose an inch from normal ride heigth, the bars will have more tension on them and make the ride stiffer. Does this sound right to everyone?
So if I put .960" bars in the car with a 383/727 and drop the nose to get the stance I want, the ride will be a little stiffer. Let me know if I have this wrong because it is all speculation at this point and I will be dropping a 440 in there later. Thanks for the help!
 
Good thought, but you actually have it backwards. The more you raise the nose of the car with the torsion bar adjuster, the stiffer the spring support effect. Lower the bars and they don't do the job as well. That's why with a slight downward rake I like my 1.00" bars better than my old .088" 's.

The other thing to watch out for is the larger diameter the torsion bar, the more resulting understeer. More and more positive caster can also increase understeer, as can adding a front sway bar or increasing front sway bar size and your steering box firmness (Stage I is lightest, then Stage II like I have, then Stage III steering box). It depends on your driving style.

Torsion bar manufacturers also caution against using larger than the 1.00" bars in conjunction with 2" drop spindles due to fit issues.

Kern-dog and Furry Frog, since you're both running the big bars, are my facts above correct from what you've seen and also does your real world experience with your car setup support this?

After reading as much as I can on this subject throughout the forum, I am wondering how much effect raising or lowering the ride stance has on the torsion bar support/ performance? I like the idea of dropping the nose an inch or so to get a better stance and thinking through the mechanics of how the torsion bars operate. It seems to me if you drop the nose an inch from normal ride heigth, the bars will have more tension on them and make the ride stiffer. Does this sound right to everyone?
So if I put .960" bars in the car with a 383/727 and drop the nose to get the stance I want, the ride will be a little stiffer. Let me know if I have this wrong because it is all speculation at this point and I will be dropping a 440 in there later. Thanks for the help!
 
I had 1.08" (IIRC) torsion bars on our '66 Charger and loved it. It had KYB's so the ride was a little harsh but man was it fun to drive! It also had a 15/16" sway bar in the rear and 1.25" in the front.

That car was a 440 powered road trip machine that took us all over the Western US very comfortably.

On the other hand I have a stock '66 Coronet with .890 bars and a (IIRC) 7/8" front sway bar and it's like a marshmallow compared to our old Charger. I'm sure the Monroe shocks don't help any lol.

If it was me I'd be looking at 1.00"+ bars, GOOD shocks (FirmFeel or Hotchkis) and greasable LCA pins with poly bushings.

Pic of old Charger : )

100_6826.jpg
 
I believe you are going the wrong way there. Others will jump in, but effectively, by lowering the front you are decreasing the preload on the torsion bars. There will probably also be an effect on bump steer as well. I have not had a wealth of experience setting up front ends, so others will probably be more qualified to tell you how much the effects would be.
 
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