Thinking about replacing my leaf springs, and I need your advice.

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cruiser

cruiser

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MOPAR brethren: My 1974 Duster has its original rear leaf spring set. Sometime before I bought the car in 2019, a previous owner installed a set of Monroe coil over rear shocks to restore the ride height to the back end of the car as the factory leaf springs were sagging over time. I'm now contemplating rebuilding the rear leaf springs (something I've never done before), but I can also buy a new set of leaf springs from ESPO Springs and Things for $220.00. These are five leaves, instead of the factory original four, but ESPO says that they'll restore the original ride height and will ride as softly as the original set. I'm looking for a very soft ride, not a performance car in any way. Just nice and soft. They also said that I could get rid of the coil over shocks and install standard shocks in the back, which I'd love to do as I like the original look. What do you think? To me, rebuilding or re-arching the original set seems like throwing good money after bad. Please weigh in with your opinions - especially if you've ever bought leaf springs from ESPO. Thanks!
 
Do you remember my advice regarding the torsion bars? Same thing. lol
 
Espo all the way. Go with the 5 leaf springs. They will be fine and provide a nice ride.
 
i agree with the above advice... i ordered a set from Espo a few weeks ago, be prepared to wait, those Duster springs are a 2 month wait , thats what the nice lady on the phone told me
 
I 3rd TMM's advice. You can't go wrong with their springs - or their customer service.

I have a pair of their HD, original height and I'm very happy.
 
I had 6 leaf springs on my 66 originally. I ordered 5 leaf springs from Espo not even looking at the originals. They have been on for 10 years and still ride and look like new.

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The previous, previous owner of my Dart GT replaced the rear leaf springs with a set of Mancini Racing 2800lb springs. I've owned the car for nearly 18 years.

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Agree with all, they are great leafs. And I know somebody that would buy your coil overs as is, to replace his aging air shocks. PM me if you want to get rid of the coil overs! Hah! Seriously regardless of your decision on coil overs you simply cannot go wrong with Espo!
 
Sublime one said:
Agree with all, they are great leafs. And I know somebody that would buy your coil overs as is, to replace his aging air shocks. PM me if you want to get rid of the coil overs! Hah! Seriously regardless of your decision on coil overs you simply cannot go wrong with Espo!
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Thanks for the input. So does everyone agree that getting rid of the coil over shocks would be a good idea if I replaced the leaf springs? Can anyone think of a reason why I would keep them (the coil overs)?
 
cruiser said:
Thanks for the input. So does everyone agree that getting rid of the coil over shocks would be a good idea if I replaced the leaf springs? Can anyone think of a reason why I would keep them (the coil overs)?
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The coil shocks are a crutch for weak springs. Also, the crossmember that serves as the upper anchor for the shocks is NOT meant to support the car, it is meant to dampen suspension movement. Look at the thickness of the metal.
Long shackles used to be popular but are also a crutch for worn springs.
 
70dart340 said:
If you have a 600 HP small block, they might be better on the track.
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My car has a REALLY small block, only displacing 225 cubic inches. No need to worry about hooking up 600 HP to the pavement. My previous 225 Duster had 79 rear wheel HP, as actually measured on the chassis dyno. I didn't think that a chassis dyno could be calibrated to accurately measure such a low power output. My quarter mile ET at the drag strip would likely be about 23 - 25 seconds, with a trap speed of around 58 mph. And no, I'm not open to a challenge race at the strip unless its against a similarly underpowered car such as one of those awful rusty six cylinder early seventies Ford Mavericks. (Yuck.) I'd insist on lane choice, of course.
 
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Another purpose of the original load leveler shocks was to enable cars to carry heavier loads without tail dragging. It sounds like you are not in the habit of carrying extra /6 blocks or heads in your trunk so do NOT reuse them with your new springs.
 
If you're bracket racing, you're still competitive. The other guy might red light after watching you run down the track for 10 seconds.
 
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70dart340 said:
If you're bracket racing, you're still competitive. The other guy might red light after watching you run down the track for 10 seconds.
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Yeah, that's true. I didn't think of that. I'd need to find a bracket race that I could definitely win, like me against my 90 year old mom in her Buick, or maybe against a guy pushing a fruit cart like you see on the street in New York City. I'd give the fruit cart guy lane choice, of course. What was that horrible mushroom shaped car from the seventies? The Pacer? They were powered by an anemic smog motor, usually missing on one of the four cylinders. I might consider that.
 
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cruiser said:
MOPAR brethren: My 1974 Duster has its original rear leaf spring set. Sometime before I bought the car in 2019, a previous owner installed a set of Monroe coil over rear shocks to restore the ride height to the back end of the car as the factory leaf springs were sagging over time. I'm now contemplating rebuilding the rear leaf springs (something I've never done before), but I can also buy a new set of leaf springs from ESPO Springs and Things for $220.00. These are five leaves, instead of the factory original four, but ESPO says that they'll restore the original ride height and will ride as softly as the original set. I'm looking for a very soft ride, not a performance car in any way. Just nice and soft. They also said that I could get rid of the coil over shocks and install standard shocks in the back, which I'd love to do as I like the original look. What do you think? To me, rebuilding or re-arching the original set seems like throwing good money after bad. Please weigh in with your opinions - especially if you've ever bought leaf springs from ESPO. Thanks!
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I haven't got them installed yet but the ESPO appear to be good quality , I have more work to do as I also am installing a 8 3/4 rear in the process of the work

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I will be receiving my 6 leaf 340 set on Tuesday, they said 2 months but it didn’t take that long..$250 plus $60 to ship..
 
Sublime one said:
Agree with all, they are great leafs. And I know somebody that would buy your coil overs as is, to replace his aging air shocks. PM me if you want to get rid of the coil overs! Hah! Seriously regardless of your decision on coil overs you simply cannot go wrong with Espo!
Click to expand...
 
cruiser said:
My previous 225 Duster had 79 rear wheel HP, as actually measured on the chassis dyno. I didn't think that a chassis dyno could be calibrated to accurately measure such a low power output. My quarter mile ET at the drag strip would likely be about 23 - 25 seconds, with a trap speed of around 58 mph.
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When you finish with your suspension upgrade, we can help you tweak that 225 until it is VERY happy! Cruise on over to the slant 6 area and learn from the guys who've done it!
 
Ricks70Duster340 said:
When you finish with your suspension upgrade, we can help you tweak that 225 until it is VERY happy! Cruise on over to the slant 6 area and learn from the guys who've done it!
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Rick - thanks for the offer. The 79 HP dyno run was on my previous Duster that I no longer own. I had a speed shop performance tune my current Duster and it runs a lot better, so I'm happy with it. But I'll keep an eye on the slant six area. Thank you for the recommendation!
 
cruiser said:
Rick - thanks for the offer. The 79 HP dyno run was on my previous Duster that I no longer own. I had a speed shop performance tune my current Duster and it runs a lot better, so I'm happy with it. But I'll keep an eye on the slant six area. Thank you for the recommendation!
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Glad you're happy with it! Think you'll be amazed at the wisdom found in that /6 area. No kidding, those guys can often make things happen that other professional shops have no clue about!
 
Watch out and watch it.I bought stock height springs from Laura and it sat too high.Make sure
you specify ride height. Their springs are good quality
 
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