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Do torsion bars wear out after time? #1481555 08/08/13 03:01 PM 08/08/13 03:01 PM
Joined: Jul 2005 Posts: 1,301 Penna 7 70satelliteguy OP pro stock
70satelliteguy OP pro stock 7 Joined: Jul 2005 Posts: 1,301 Penna	I have the Drag racing diameter size torsion bars on my 70 B body now for about 6 years ,probably 500+ passes on them. The car is heavy(3600 lbs.) .I am not having any problems that I know of but was just wondering if this is a part that should be replaced at some time. Thanks Mike

Re: Do torsion bars wear out after time? [Re: 70satelliteguy] #1481556 08/08/13 03:52 PM 08/08/13 03:52 PM
Joined: Jan 2003 Posts: 31,050 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 31,050 Oregon	Springs only wear out if they are overstressed. If you stay below the fatigue life on spring steel then the life is infinite. Having said that, drag bars can be overstressed in a 3600 lb car, especially if you have a lot of front end travel. So yeah, I'd replace them every 5 years or so if it was my car.

Re: Do torsion bars wear out after time? [Re: 70satelliteguy] #1481557 08/08/13 04:23 PM 08/08/13 04:23 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	yes... a spring is a spring...if it jounces a bit harder than normal it takes its toll

Re: Do torsion bars wear out after time? [Re: 70satelliteguy] #1481558 08/08/13 04:52 PM 08/08/13 04:52 PM
Joined: Jul 2005 Posts: 1,301 Penna 7 70satelliteguy OP pro stock
70satelliteguy OP pro stock 7 Joined: Jul 2005 Posts: 1,301 Penna	Thanks for the reply's The car does probably stress the bars some with 1.30 60 fts. and wheelstands. Guess I will replace them this winter just to be sure. Mike

Re: Do torsion bars wear out after time? [Re: 70satelliteguy] #1481559 08/08/13 05:51 PM 08/08/13 05:51 PM
Joined: Sep 2003 Posts: 2,008 Sweet Home Alabama M MRMOPAR622 top fuel
MRMOPAR622 top fuel M Joined: Sep 2003 Posts: 2,008 Sweet Home Alabama	I would think on a Drag car the weaker the better!Was that not the reason we used to replace the torsion bars off all the V8 B body cars with the torsion bars of the 6 cylinder cars,weaker bars? "To Be The Man'You Have Got To Beat The Man" "T/D and Pro-Bracket Racer"

Re: Do torsion bars wear out after time? [Re: AndyF] #1481560 08/08/13 09:24 PM 08/08/13 09:24 PM
Joined: Dec 2003 Posts: 22,696 Bitopia J jcc If you can't dazzle em with diamonds..
jcc If you can't dazzle em with diamonds.. J Joined: Dec 2003 Posts: 22,696 Bitopia	Quote: Springs only wear out if they are overstressed. If you stay below the fatigue life on spring steel then the life is infinite. Having said that, drag bars can be overstressed in a 3600 lb car, especially if you have a lot of front end travel. So yeah, I'd replace them every 5 years or so if it was my car. Since on Mopars, they are inherently limited by design, as to how far they can be maximum loaded/twisted, the difference that matters here is how much preload/twist is dialed in for static ride height, and then adding maximum travel thru bumps/wheelstands, etc, which then approaches the over stressed area. I am surprised there is not a value published/known for maximum degrees of twist allowed for each bar. And I always heard as a rough idea loading typical steel to approx 70% tensile strength gives about 6-10,000,000 cycles of useful life. As you start approaching 100% it starts dropping faster, just to put a number on "infinite". Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.

Re: Do torsion bars wear out after time? [Re: jcc] #1481561 08/08/13 09:50 PM 08/08/13 09:50 PM
Joined: Jan 2003 Posts: 27,421 Balt. Md 3 383man Too Many Posts
383man Too Many Posts 3 Joined: Jan 2003 Posts: 27,421 Balt. Md	All I can say is I have owned 60's and 70's Mopars since 1974 and I have never broken or wore out a torsion bar. I have heard of some people having one break but I have not seen this. In fact the bars in my 63 are still the original stock 383 torsion bars. Ron

Re: Do torsion bars wear out after time? [Re: 383man] #1481562 08/08/13 11:29 PM 08/08/13 11:29 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: All I can say is I have owned 60's and 70's Mopars since 1974 and I have never broken or wore out a torsion bar. I have heard of some people having one break but I have not seen this. In fact the bars in my 63 are still the original stock 383 torsion bars. Ron Are you running stock bars... stock bars will last for damn near ever if your not pulling wheelies or run on bad roads... when you jounce them more than the normal they start to sag.... I worked on the F-body transvers suspension project and even during the preload I had 4 or 5 bars blow.. when they did blow(they were under a shield) it was like a bomb going off.. and sent a razor sharp chunk flying but was contained in my fixture.. when ever it did blow.. most of the building came to see what happened

Re: Do torsion bars wear out after time? [Re: MR_P_BODY] #1481563 08/08/13 11:51 PM 08/08/13 11:51 PM
Joined: Jan 2004 Posts: 903 Saskatchewan, Canada cudabin super stock
cudabin super stock Joined: Jan 2004 Posts: 903 Saskatchewan, Canada	The drivers front torsion bar in my (heavy) 440 six pack Super Bee is sagging as it is cranked all the way up while the passenger side adjusting bolt is only half way in... Original .920 bars. I am ordering 2 new ones. Cheers, Arnie 67 Cuda 8.48@ 158.7 mph 1.18 60' 2,600 DA(so far...) 70 Super Bee 440 Six Pack 4-speed. 13.2 @ 104 Stock exhaust/Street tires.

Re: Do torsion bars wear out after time? [Re: 383man] #1481564 08/09/13 12:01 AM 08/09/13 12:01 AM
Joined: Jan 2003 Posts: 21,076 Niles , Ohio T therocks oh wait.but hey.lets see.oh yeah.
therocks oh wait.but hey.lets see.oh yeah. T Joined: Jan 2003 Posts: 21,076 Niles , Ohio	Ron I started running Mopars in 65.I only had one bar snap/It was my 67 Plymouth Fury.Parked it and came out the next day to go to work.The one side was snapped.My old man started driving them in the 50s.Thats the only one Ive ever seen snapped.I had one of the trans verse one at the shop that snapped.That was at least 30 years ago.Rocky Last edited by therocks; 08/09/13 12:02 AM. Chrysler Firepower

Re: Do torsion bars wear out after time? [Re: therocks] #1481565 08/09/13 09:35 AM 08/09/13 09:35 AM
Joined: Jan 2003 Posts: 17,869 S.E. Michigan ZIPPY I Live Here
ZIPPY I Live Here Joined: Jan 2003 Posts: 17,869 S.E. Michigan	The only vehicle I had that broke a torsion bar was my '78 B body. I feel the reason it broke is because the ends of that bar were rusted into the sockets but maybe I am off base. I had just ran an errand, got out of the car and BLAM! Like a gun going off. Instant low rider, but only on one side Rich H. Esse Quam Videri

Re: Do torsion bars wear out after time? [Re: ZIPPY] #1481566 08/09/13 10:56 AM 08/09/13 10:56 AM
Joined: Jan 2003 Posts: 75,047 U.S.S.A. JohnRR I Win
JohnRR I Win Joined: Jan 2003 Posts: 75,047 U.S.S.A.	I had a 78 M body that only had about 70k miles on it when the T bar broke , the car had that many miles on it when it about 25 years old , nice and not rusty by any means, my brother was driving it , hit a pothole and BANG !

Re: Do torsion bars wear out after time? [Re: JohnRR] #1481567 08/09/13 11:52 AM 08/09/13 11:52 AM
Joined: Jul 2005 Posts: 1,301 Penna 7 70satelliteguy OP pro stock
70satelliteguy OP pro stock 7 Joined: Jul 2005 Posts: 1,301 Penna	They are not that expensive. I am still planning on new bars over the winter. Mike

Re: Do torsion bars wear out after time? [Re: ZIPPY] #1481568 08/09/13 12:49 PM 08/09/13 12:49 PM
Joined: Jan 2003 Posts: 31,050 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 31,050 Oregon	Both torsion bars in the Duster drag car that I bought a few years ago were twisted. The bars had been installed on the wrong side and I had to beat on them pretty hard to remove them. When I got them out and inspected them I could see that they were both twisted. So something happened along the way.

Re: Do torsion bars wear out after time? [Re: AndyF] #1481569 08/09/13 01:48 PM 08/09/13 01:48 PM
Joined: Dec 2009 Posts: 284 STL ,MO H Handygun enthusiast
Handygun enthusiast H Joined: Dec 2009 Posts: 284 STL ,MO	Broke a bar in a 69 Coro once. Parked at the pump while I was in paying. 318 car, early eighties.

Re: Do torsion bars wear out after time? [Re: MR_P_BODY] #1481570 08/09/13 02:00 PM 08/09/13 02:00 PM
Joined: Jan 2003 Posts: 27,421 Balt. Md 3 383man Too Many Posts
383man Too Many Posts 3 Joined: Jan 2003 Posts: 27,421 Balt. Md	Quote: Quote: All I can say is I have owned 60's and 70's Mopars since 1974 and I have never broken or wore out a torsion bar. I have heard of some people having one break but I have not seen this. In fact the bars in my 63 are still the original stock 383 torsion bars. Ron Are you running stock bars... stock bars will last for damn near ever if your not pulling wheelies or run on bad roads... when you jounce them more than the normal they start to sag.... I worked on the F-body transvers suspension project and even during the preload I had 4 or 5 bars blow.. when they did blow(they were under a shield) it was like a bomb going off.. and sent a razor sharp chunk flying but was contained in my fixture.. when ever it did blow.. most of the building came to see what happened Yes I am running the stock bars. As like always on my cars they are adjusted where I like them with plenty of adjustment left. Like I said I have heard of them breaking but I have never had one break on me and never even seen one break but I know they can break. And I sure dont go around pulling wheelies everyday. Heck I am glad to get 6 inches or more off the ground when it hooks. I never have cared for the F-body (Aspen & Volare) torsion bar setup. Ron Last edited by 383man; 08/09/13 02:03 PM.

Re: Do torsion bars wear out after time? [Re: therocks] #1481571 08/09/13 02:07 PM 08/09/13 02:07 PM
Joined: Jan 2003 Posts: 27,421 Balt. Md 3 383man Too Many Posts
383man Too Many Posts 3 Joined: Jan 2003 Posts: 27,421 Balt. Md	Quote: Ron I started running Mopars in 65.I only had one bar snap/It was my 67 Plymouth Fury.Parked it and came out the next day to go to work.The one side was snapped.My old man started driving them in the 50s.Thats the only one Ive ever seen snapped.I had one of the trans verse one at the shop that snapped.That was at least 30 years ago.Rocky I guess I have been lucky so far. I wondered how the bars would act if put in on the wrong side since they would twist the oppisite way ? Now watch my luck I will have a bar break this week on me. Ron

Re: Do torsion bars wear out after time? [Re: 383man] #1481572 08/09/13 02:10 PM 08/09/13 02:10 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Yes I am running the stock bars. As like always on my cars they are adjusted where I like them with plenty of adjustment left. Like I said I have heard of them breaking but I have never had one break on me and never even seen one break but I know they can break. And I sure dont go around pulling wheelies everyday. Heck I am glad to get 6 inches or more off the ground when it hooks. I never have cared for the F-body (Aspen & Volare) torsion bar setup. Ron A lot of hot rodders love the F & M body front suspension.. with a few turns you can have it way up or down low plus its a self contained unit

Re: Do torsion bars wear out after time? [Re: 70satelliteguy] #1481573 08/09/13 02:17 PM 08/09/13 02:17 PM
Joined: Aug 2004 Posts: 204 Indiana MFR426 enthusiast
MFR426 enthusiast Joined: Aug 2004 Posts: 204 Indiana	I know I am aging myself, but back in 1957 when my parents bought their new 57 Savoy, after about 6 months we had one break. Since mom worked at the dealer we found out that they had defective ones that the metal was not up to specs. This was corrected and you didn't hear of them breaking until the Aspen/Volare days which I can attest too as I used to have the broken one under my house and I didn't move it so wonder if it is still there since I moved 10 years ago! Ha! Metal is metal and will have a stress point at some time, but when that will be is dependent on amount of stress and number of movements and each one is probably different. We have spares just in case!

Re: Do torsion bars wear out after time? [Re: 383man] #1481574 08/09/13 04:52 PM 08/09/13 04:52 PM
Joined: Jan 2003 Posts: 19,375 Las Vegas Al_Alguire I Live Here
Al_Alguire I Live Here Joined: Jan 2003 Posts: 19,375 Las Vegas	My old Duster had a torsion bar "wear out". Found it after unloading it at the MATS a number of years ago. Had to use a floor jack to get it out of the trailer and went to the swap area to buy replacements. Curiously enough it had the race/6 torsion bars in it, only replacements I could find were 340 bars and car made its quickest runs ever in Vegas that weekend. "I am not ashamed to confess I am ignorant of what I do not know." "It's never wrong to do the right thing"

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