Rear '68 Coilover system, bye bye leaf springs...

CrisNavarro

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Hi!
My next step is to change the rear leaf springs suspensions system for a coilover system.
I saw some options on the internet, I think here are the best ones:
Street or Track
Global West
Total Control Products
Ridetech
But this brands are focused for high perfromance, like for track cars.
I am going to drive on streets and I am looking for something cheaper, some recommendation? Someone with experience to recommend 3 or 4 links?
What do you think about something like this?
s-l1600.jpg
 
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wicked93gs

10 Year Member
Sep 30, 2006
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If you are not wanting it for performance....what swap from leaf springs at all? Leaf springs are perfectly sufficient for the street, there are a lot of different leaf options out there that will ride very nicely paired with the correct shock.
 
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CrisNavarro

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If you are not wanting it for performance....what swap from leaf springs at all? Leaf springs are perfectly sufficient for the street, there are a lot of different leaf options out there that will ride very nicely paired with the correct shock.
Thanks for your opinion. Yes I want to have more performance, 347 stroker. I like more the coilover system, but I don't know really good which one to choose.
 

wicked93gs

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Thanks for your opinion. Yes I want to have more performance, 347 stroker. I like more the coilover system, but I don't know really good which one to choose.

Street or Track is the one I would go with. I know you want to save money...but SoT's coilover systems(front and rear) always have positive reviews about improving ride quality over the stock components, even though they are performance orientated. They have "street" kits in addition to "sport" kits. In the end, if you are looking for improved ride...its not the spring that is going to give it to you, its the SHOCK, in particular, matching the correct shock to the correct spring will result in the best performance ...or alternatively the best ride. I would not touch a cheap coil over kit with a 10 foot pole, all that cheap mean is that no real time and effort went into matching springs and shocks, and do research and development time went into testing. Sure...it might bolt up and allow you to raise or lower your car with a coilover wrench....but whats the point of that if it doesn't improve lap times, slalom times, or skidpad times? Ride height adjustments can be made using lowering blocks or cutting coil springs...if you arent getting actual performance out of a coil over setup you are wasting your money.

Take that 4 link you listed above. Not knowing exactly what kit it is, I can't say anything about it one way or the other, but looking at it, I see links without heim joints, relying on bushings....which is fine, but it means that there is deflection that would not exist in a higher quality kit. I see a bunch of weld-on brackets, which are also fine, but its a big risk to take if you find out you are unhappy with the final product, every time you weld a bracket onto a rear axle, you are taking the chance of warping the tubes(well in reality you ARE warping the tubes) there is a good chance of ruining a housing if you change the setup multiple times because you weren't happy with the first setup you chose. I also see what look to be cheap shocks that are bound to give a less-than-ideal ride. Shocks are the one part of the suspension you really don't want to go cheap with.

What I am getting at here is that a cheap kit will cost you more in the end than buying a more expensive kit that you KNOW many people are happy with because you will be changing things out multiple times until you are happy with it. What happens if you buy that kit you listed and it rides like most cheap coilover kits ride...harsh and uncomfortable because of poor shock and spring choices? What happens if it has a tendency to bind in corners because not enough actual driving and testing has been done with it?
 
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rbohm

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wicked93gs is right on this, the kit you showed is cheap at best. you can mitigate a few issues indicated by swapping the rubber bushings at one end of each link bar with a heim joint. also while teh kit is probably quite cheap, you can again mitigate some of the issues by paying attention to details when installing it. measure several times, then cut once. take your time and get every thing right before you do any final welding. and there are ways to mitigate any axle housing warping by using several tack welds and jumping around as you weld. ultimately tying each tack weld together. there are also ways to support the axle housing to prevent warppage.
 

CrisNavarro

Member
Apr 29, 2020
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Street or Track is the one I would go with. I know you want to save money...but SoT's coilover systems(front and rear) always have positive reviews about improving ride quality over the stock components, even though they are performance orientated. They have "street" kits in addition to "sport" kits. In the end, if you are looking for improved ride...its not the spring that is going to give it to you, its the SHOCK, in particular, matching the correct shock to the correct spring will result in the best performance ...or alternatively the best ride. I would not touch a cheap coil over kit with a 10 foot pole, all that cheap mean is that no real time and effort went into matching springs and shocks, and do research and development time went into testing. Sure...it might bolt up and allow you to raise or lower your car with a coilover wrench....but whats the point of that if it doesn't improve lap times, slalom times, or skidpad times? Ride height adjustments can be made using lowering blocks or cutting coil springs...if you arent getting actual performance out of a coil over setup you are wasting your money.

Take that 4 link you listed above. Not knowing exactly what kit it is, I can't say anything about it one way or the other, but looking at it, I see links without heim joints, relying on bushings....which is fine, but it means that there is deflection that would not exist in a higher quality kit. I see a bunch of weld-on brackets, which are also fine, but its a big risk to take if you find out you are unhappy with the final product, every time you weld a bracket onto a rear axle, you are taking the chance of warping the tubes(well in reality you ARE warping the tubes) there is a good chance of ruining a housing if you change the setup multiple times because you weren't happy with the first setup you chose. I also see what look to be cheap shocks that are bound to give a less-than-ideal ride. Shocks are the one part of the suspension you really don't want to go cheap with.

What I am getting at here is that a cheap kit will cost you more in the end than buying a more expensive kit that you KNOW many people are happy with because you will be changing things out multiple times until you are happy with it. What happens if you buy that kit you listed and it rides like most cheap coilover kits ride...harsh and uncomfortable because of poor shock and spring choices? What happens if it has a tendency to bind in corners because not enough actual driving and testing has been done with it?
Hi @wicked93gs,
first to all thank you for your words.
Maybe I didn't use the correct words to express my self.
I know that the shocks must be for high quality, especially if we are looking to improve the dynamics of the car, be it for street, sport street or racing.
I agree with you in your comments and in fact I think like you.
My idea is to install a double wishbone in the front, double adjust high and hardness and a coliover system also for the rear.
I have to choose a shock system with good quality, adjustable in two positions, its price is justified.
The idea is no to exceed the price in a system that is more for drags or tracks.
Would the 4 link system be the most suitable?
Are there other systems that can also be valid for "sport street" use?
TIA
 

CrisNavarro

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Apr 29, 2020
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wicked93gs is right on this, the kit you showed is cheap at best. you can mitigate a few issues indicated by swapping the rubber bushings at one end of each link bar with a heim joint. also while teh kit is probably quite cheap, you can again mitigate some of the issues by paying attention to details when installing it. measure several times, then cut once. take your time and get every thing right before you do any final welding. and there are ways to mitigate any axle housing warping by using several tack welds and jumping around as you weld. ultimately tying each tack weld together. there are also ways to support the axle housing to prevent warppage.
Hi rbohm,
thanks for your tipps.
If I finally buy this system or another, I will send the information to the welder.
TIA.
 

CrisNavarro

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I found a guy in Instagram that installed a Cobra IRS 03-04 rear suspension system in a 67 or 68, how do you find this idea?
 

wicked93gs

10 Year Member
Sep 30, 2006
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Is not a 4 link suspension system, somebody knows about it?
Cobra IRS.jpg

There was a guy on here about 10 years ago that did this swap, but I honestly can't remember any details.

If I were going to adapt the IRS from another car I think I would use the Miata cradle setup...its more compact and I have one with a 8.8" Ford carrier already mounted to it...regardless of which IRS setup you go with though all the swaps are pretty much one-off....think there is a writeup somewhere about adapting a Jag rear IRS too.
 
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CrisNavarro

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There was a guy on here about 10 years ago that did this swap, but I honestly can't remember any details.

If I were going to adapt the IRS from another car I think I would use the Miata cradle setup...its more compact and I have one with a 8.8" Ford carrier already mounted to it...regardless of which IRS setup you go with though all the swaps are pretty much one-off....think there is a writeup somewhere about adapting a Jag rear IRS too.
wicked93gs
Thank you! Looks like this IRS CObra 03-04 is not the best option for a 8.8" Mountaineer... :( :(
 

CrisNavarro

Member
Apr 29, 2020
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There was a guy on here about 10 years ago that did this swap, but I honestly can't remember any details.

If I were going to adapt the IRS from another car I think I would use the Miata cradle setup...its more compact and I have one with a 8.8" Ford carrier already mounted to it...regardless of which IRS setup you go with though all the swaps are pretty much one-off....think there is a writeup somewhere about adapting a Jag rear IRS too.
Hi wicked93gs!
Do you remember this guy with the IRS Cobra? Or maybe another example in this forum with some pics? Thank you in advance!