A more definitive STR suspension upgrade thread

Kumba

Kumba

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And by definitive I mean theoretical but first a little background. I've been doing some research into swapping out the suspension components of the LS for those from an '03-05 Jaguar S-Type. This would give me an improved handling, lower stance, and the brembo brakes. What I have found leads me to believe it's still possible, but requires some pretty big conversions.

Starting in 2003 Jaguar converted the lower control arm to be a two-piece articulated design. There is the main rear piece of the LCA which supports the weight of the car and then a second arm attached by a bolt at an angle. This gave them increased suspension geometry control over the full suspension travel as well as an almost 10% increase in the rigidity of the suspension.

The down side of this means that the front k-member would have to be changed out to do the conversion. There is also no guarantee that the k-member bolts up directly, or that the UCA is positioned in the right spot to maintain geometry. I feel fairly confident that it would all bolt up and work properly though.

So, here's what it would take to do an 03-05 STR suspension conversion on an LS:
Front K-Member
Front Lower Control Arms (both pieces, both sides)
Front Upper Control Arms (both sides)
Knuckles for all 4 corners
Brake Calipers for all 4 corners
E-Brake Calipers for the rear (both sides)
Brake Caliper Brackets for all 4 corners
Brake Rotors for all 4 corners
Brake pads for all 4 corners
e-brake cables for rears
STR Springs, shocks, and everything in between for all 4 corners
Front and Rear sway bars
A keg of beer
lots of cussing
misc hardware


So yeah, that's all. Probably $3K worth of parts, not counting labor.

Here's a computer rendering of the front k-member. You can see how the forward small arm is mounted at a different angle. This is what helps stiffen the suspension and maintain geometry as it flexes:
2006-jaguar-s-type-r-8w.jpg
 
Kumba, is this actually a goal you want to achieve or you just want to see if it's possible?

I think having an LS body sitting on a Jaguar STR suspension would be stellar.

Also, is the estimate you posted for used parts or new?
 
If it reaches $4k it would be easier to just buy the stoptechs. But the str swap will also lower the car and make it handle better. Hmmmm.
 
05 LS8 said:
Kumba, is this actually a goal you want to achieve or you just want to see if it's possible?

I think having an LS body sitting on a Jaguar STR suspension would be stellar.

Also, is the estimate you posted for used parts or new?
Click to expand...


It is something I am interested in doing. There is a definite difference in feel between the LS and a Gen2 S-Type, let alone the STR. And that $3K is a mix of aftermarket and used. The UCA would more then likely have to be OEM. But H&R Springs, Bilstein shocks, and the rest of the parts to make the shock "kit" would be around $1100. The control arms and knuckles are around $100/ea depending upon where you get it from car-part.com. The k-member would be a pain shipping wise. The 4 brembo calipers are around $5-600 for the set from e-bay.

$3K might be where you would want to start. It could easily be another $1-2K depending upon how much of a hurry you are in and how many OEM new parts you get versus salvaged parts. Since I am in no hurry, I can take my time and just start collecting parts when I find them inexpensively.

The best solution would be to find a t-boned STR and buy it for salvage. Take the suspension off and sell the engine/trans off to recoup some costs. Although I would probably keep the engine and look at tossing it in the LS instead.

At some point, re-skinning an STR starts to sound better. LOL
 
Kumba, I'm still working on my little project. I should be getting parts sometime next week just for a mock up. I think I have everything figured in including a smooth body roll transfer. I know it's taking some time, but math isn't easy when it comes to suspension. I've had 3 MKIII Supras in my time, and I know how horrid suspensions can be. Hitting it right the first time never happens, but I'm real close because the way the LS is setup.
 
Well, the suspension setup of an STR would address things outside of what just a shock and spring can do. It would be an interesting conversion.
 
I still think it sounds like an awesome plan. $3k is actually pretty reasonable for a full suspension and brake swap if you think about it. I mean hell Stoptechs for the LS are $4k alone!
 
jolinc01 said:
I still think it sounds like an awesome plan. $3k is actually pretty reasonable for a full suspension and brake swap if you think about it. I mean hell Stoptechs for the LS are $4k alone!
Click to expand...

Even more.

$2695 a piece for two rotors, calipers, pads and lines.
 
If you just wanted bigger breaks it would be cheaper to buy the rotors for the STR, slap them on the car, pick calipers of your liking, and then fab up a mounting bracket. You could even fab a bracket for the STR's brembo calipers if you want. The rears are basically a direct swap with a knuckle change and e-brake cables/calipers. I would highly suggest you keep the e-brake function, although you can do without them.

The STR swaybars might swap over without any subframe nonsense too. That gets you better body control. It is stiffer then the regular s-type.

All the STR conversion has to offer at that point is an improved geometry and rigidity. That isn't nothing to sneeze at, but I am not sure how great the benefit would be. All I would really expect is better feel for over and under steer, with less unstabling at extreme suspension travel. I.E better control in a slalom where the car is sloshing left and right.
 
Kumba said:
It is something I am interested in doing. There is a definite difference in feel between the LS and a Gen2 S-Type, let alone the STR. And that $3K is a mix of aftermarket and used. The UCA would more then likely have to be OEM. But H&R Springs, Bilstein shocks, and the rest of the parts to make the shock "kit" would be around $1100. The control arms and knuckles are around $100/ea depending upon where you get it from car-part.com. The k-member would be a pain shipping wise. The 4 brembo calipers are around $5-600 for the set from e-bay.

$3K might be where you would want to start. It could easily be another $1-2K depending upon how much of a hurry you are in and how many OEM new parts you get versus salvaged parts. Since I am in no hurry, I can take my time and just start collecting parts when I find them inexpensively.

The best solution would be to find a t-boned STR and buy it for salvage. Take the suspension off and sell the engine/trans off to recoup some costs. Although I would probably keep the engine and look at tossing it in the LS instead.

At some point, re-skinning an STR starts to sound better. LOL
Click to expand...


Gotcha! The $3k should cover it, but i do have a feeling by the time you done, it will be another thousand or two as you had mentioned for all the "unforeseen".

I am assuming you are planning on hanging on the LS for a long time? If not, it may be worth just buying a STR, this way you get the extra power.. http://www.cars.com/go/search/detai...pp=50&feedSegId=28705&aff=national&listType=1
 
05 LS8 said:
Gotcha! The $3k should cover it, but i do have a feeling by the time you done, it will be another thousand or two as you had mentioned for all the "unforeseen".

I am assuming you are planning on hanging on the LS for a long time? If not, it may be worth just buying a STR, this way you get the extra power..
Click to expand...

You know, if every time I looked at the S-Type I didn't think of the Batmobile from the Tim Burton Batman films with Michael Keaton then I probably would just buy the STR. But damn, that whole retro jag look thing just does nothing for me. In fact, it's the biggest thing I hate about the S-Type. As far as driving it goes the shifter sucks. Much prefer the select shift. Also not a fan of wood veneer. But the drive and interior are nice.

But at some point, the cost of transplanting a Gen2 front and rear clip on it does become a valid question. Althought they have a body line in the sheet metal that does down the side that the LS doesn't have.
 
I'm actually considering going forward with this front-end conversion. I don't suppose anyone has the two braces dropped out of their car at the moment and can give me a measurement on where the bolt holes are relative to the body? :D
 
Pan1019 said:
Reading this made me happy. Right on!
Click to expand...

Well, the kicker is that whether or not the bolt holes in the body line up with the Jag K-Member. Unfortunately there are only two ways to find out.

1) Measure the hole spacing in the Jag K-member and where the LS holes are for the subframe braces
2) The amish method, which is to drop the engine and everything out and just try to bolt it together.

Unfortunately option 2 means I have to also buy the full suspension deal. Either that or take my old suspension off and then put it back on after test-fitting the Jag k-member. So, I'm trying to make option 1 happen. When I crawl under there this weekend to look at the subframe braces I will see if there is a good accurate way to measure what is there. As long as I get to within a 1/4" or better measurement then I am sure it will work or I can make it work. Once I am confident the bolt holes will line up it's just a matter of collecting all the pieces. :)

I'm hoping what I can do is strip the unsprung suspension off the front, unbolt the steering shaft after marking how it lines up, and hang the engine from a cherry picker while I drop the braces and put in the jag k-member. I really don't want to have to completely disconnect the engine and pull it out. Still might end up buying a second beater pickup to drive around while I work on this pig. A little ranger sounds fine. Be easy to pick up parts too.
 
Kumba said:
Still might end up buying a second beater pickup to drive around while I work on this pig. A little ranger sounds fine. Be easy to pick up parts too.
Click to expand...

Every true gearhead needs a parts-hauler. :cool:

Plus, you can make it faster with all of the stickers you accumulate.

IMG_4134.jpg
 
^ Not true. Extra added weight take away horsepower.

Also, the edges of the stickers catch the wind, which slow you down as well.
 
05 LS8 said:
^ Not true. Extra added weight take away horsepower.

Also, the edges of the stickers catch the wind, which slow you down as well.
Click to expand...

No, no, no. The edges that stick out are on the back side which acts like a spoiler. Stickers are the only known items that add horsepower without adding weight.
 
See that's what I bought my f 150 for was to dd and be a parts hauler. Then I saw how much cheaper and easier it was to modify then the mark :lol:
 
LS4me said:
No, no, no. The edges that stick out are on the back side which acts like a spoiler. Stickers are the only known items that add horsepower without adding weight.
Click to expand...

Newton would attest to my post that it is accurate.
 
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