Between Two Suspension Setups

[08Racecraft420S]

Hey everyone, this is my first post in here, but I’ve been reading and researching as much as I can on here, the TMO FB group, and the Corner Ponies FB group trying to get a solid game plan for my new to me 2008 Saleen/Racecraft 420S. I apologize in advance for the lengthy post .

As of now, the only suspension modification is a Whiteline Watts link kit in the rear. Otherwise, it’s on the original 64k mile Racecraft suspension. Looking for a solid dual-purpose setup that is 80%+ driven on the street with the occasional autocross and/or HPDE. As of now, I’ve narrowed it down between the Vorshlag StreetPro kit with the Eibach Pro 05-09 springs and the Cortex Racing single adjustables with offset strut housings and Koni internals and their “street valving” option.

My plan is to run a 19x11 squared setup with extended front studs and spacers (width spacers will depend on which suspension setup I’ll go with due to one having offset strut housings). My thought process is if I went with the Cortex setup, I could get away with a slightly smaller front spacer as well as possibly not having to run quite as much negative camber to prevent poke (more like ~-2° instead of ~3°). However, the cost is more and I’m not sure I’d really see the full benefit of a coilover. I like the idea of the StreetPro setup because of its simplicity and cost-effectiveness.

Again, the car will be majority street/mountain road driven and I’ve considered going simple with a 19x10 and 285/35/19 squared setup because of that, but I feel like I’d regret not going ahead and going with 19x11’s and 305’s both for functionality and looks alike.

Any help or insight between these two suspension options and/or my thought process would be greatly appreciated.

 

[Dave_W]

Is there anything you like or don't like about your current setup? Is it just that the shocks are getting tired, or are you looking to change the handling balance and/or ride quality in a particular way? The 420S adds a Whipple-type supercharger to a Mustang GT, right? The addition of the supercharger adds weight on the nose, which should be considered when choosing front spring rates.

The Saleen Racecraft springs supposedly "lower your stock Mustang GT approximately 1.5" in the front and 1.3" in the rear." Which is about the same as the Eibach Pro 05-10 springs you mention that Vorshlag offer. From the description, the Saleen Racecraft setup seems to be pretty similar to most lowering kits, though there's nothing specific on spring rates. A MotorTrend review of the 420S also notes a stiffer front way bar - a good idea is to measure it's diameter so you can mention it when discussing spring rates with any vendor.

As you can see, the Vorshlag kit uses "stock-style" lowering springs and is not height-adustable, nor are the Bilstein shocks adjustable for stiffness. The Cortex kit uses race-style standard-diameter springs (2.5" ID?), all corners are height-adjustable, and the Konis adjust high-speed rebound valving. Also, the Vorshlag kit keeps the rear springs in the stock location, whereas the Cortex kit changes to a coilover rear. You definitely get more adjustability in the Cortex kit, but it also costs about $1K more.

Another option you might consider is the Ground Control Koni kit. It offers single-adjustable Konis, race-style springs, and height adjustability like the Cortex kit, with stock rear spring location like the Vorshlag kit. You can upgrade to Koni "race" shocks, which are revalved for stiffer springs and may be shortened to prevent bottoming the shock on bumps when lowered (it could be that the standard GC Konis also use shortened bodies). You can even step up to double-adjustable (separate rebound and compression) struts/shocks and still be under the Cortex price.

All three of these vendors are knowledgable and worth talking to so you can benefit from that knowledge, especially with the differences beween your Saleen vs. a standard GT. I'd describe the Vorshlag kit as the "easy button" setup choice, since there's no real adjustability to anything. No adjustability means you can't make things worse. If you're happy with your current springs (ride height and stiffness), you might want to talk to Vorshlag about re-using the Racecraft springs on their Bilstein kit. If you do that, you should measure the distance from the top strut bolt to the spring perch on your current strut and let them know - there's a chance the spring perch location on the Racecraft is different than the Bilstein, which would affect ride height. Stepping up to either the Cortex or GC kit gives you the ability to adjust shock damping, ride height and corner weights, and change spring rates relatively inexpensively.

 

[08Racecraft420S]

Is there anything you like or don't like about your current setup? Is it just that the shocks are getting tired, or are you looking to change the handling balance and/or ride quality in a particular way? The 420S adds a Whipple-type supercharger to a Mustang GT, right? The addition of the supercharger adds weight on the nose, which should be considered when choosing front spring rates.

The Saleen Racecraft springs supposedly "lower your stock Mustang GT approximately 1.5" in the front and 1.3" in the rear." Which is about the same as the Eibach Pro 05-10 springs you mention that Vorshlag offer. From the description, the Saleen Racecraft setup seems to be pretty similar to most lowering kits, though there's nothing specific on spring rates. A MotorTrend review of the 420S also notes a stiffer front way bar - a good idea is to measure it's diameter so you can mention it when discussing spring rates with any vendor.

As you can see, the Vorshlag kit uses "stock-style" lowering springs and is not height-adustable, nor are the Bilstein shocks adjustable for stiffness. The Cortex kit uses race-style standard-diameter springs (2.5" ID?), all corners are height-adjustable, and the Konis adjust high-speed rebound valving. Also, the Vorshlag kit keeps the rear springs in the stock location, whereas the Cortex kit changes to a coilover rear. You definitely get more adjustability in the Cortex kit, but it also costs about $1K more.

Another option you might consider is the Ground Control Koni kit. It offers single-adjustable Konis, race-style springs, and height adjustability like the Cortex kit, with stock rear spring location like the Vorshlag kit. You can upgrade to Koni "race" shocks, which are revalved for stiffer springs and may be shortened to prevent bottoming the shock on bumps when lowered (it could be that the standard GC Konis also use shortened bodies). You can even step up to double-adjustable (separate rebound and compression) struts/shocks and still be under the Cortex price.

All three of these vendors are knowledgable and worth talking to so you can benefit from that knowledge, especially with the differences beween your Saleen vs. a standard GT. I'd describe the Vorshlag kit as the "easy button" setup choice, since there's no real adjustability to anything. No adjustability means you can't make things worse. If you're happy with your current springs (ride height and stiffness), you might want to talk to Vorshlag about re-using the Racecraft springs on their Bilstein kit. If you do that, you should measure the distance from the top strut bolt to the spring perch on your current strut and let them know - there's a chance the spring perch location on the Racecraft is different than the Bilstein, which would affect ride height. Stepping up to either the Cortex or GC kit gives you the ability to adjust shock damping, ride height and corner weights, and change spring rates relatively inexpensively.

Thank you for the reply! Yes it is supercharged and currently makes just over 460whp. I’ll definitely look into GC as well. It honestly rides fine, but like you said, the Vorshlag is like an easy button with everything coming pre-assembled including CC plates instead of me having to disassemble my current struts and then reassemble with the new struts and CC plates. I also tend to go a bit overboard for my needs with all my vehicles whether it be in the offroad world or performance cars. So that being said, the Cortex kit is probably overkill for my needs, but I’m perfectly okay with that haha. Plus like I said, I like the idea of offset strut housings so that I can run 19x11’s and 305’s with a slightly smaller spacer. Therefore I wouldn’t have to run quite as much negative camber to keep the front tires from “poking”. Was thinking of trying a 18-20mm spacer instead of the more “typical 25mm spacer if I go with the Cortex kit. Is my thinking on this correct?

I also wouldn’t mind a slightly stiffer ride with more control, but also don’t want it overly harsh. Aka why I would go with the street valved kit lol. I plan on adding rear LCA’s and relocation brackets on top of whatever kit I go with. I will also measure the front sway bar to confirm size.

If I decide on the Cortex front coilovers, is there a rear setup that you/y’all would recommend if I didn’t want to spend the money on the rear coilovers? Maybe leave the rear Racecraft springs and upgrade to some Bilstein HD’s or Koni’s? If I did go with their coilovers, do they limit the ability to run the wider wheels/tires like I’ve read other rear coilovers do? Thanks!

 

[cgornowich]

Hello 08Racecraft420S,

As luck would have it, I also have a 2008 Racecraft 420S in Artic White. I've swapped out a lot of parts in hopes of finding the "best combination" and I can tell you, from this side of the fence, I should have left her mostly stock. All the parts added a very small performance improvements and left her borderline for street use. My advice would be to enjoy her on the street and get a second beater for autocross or HPDE. Here's why:

Just go to 22.20 minutes...

There is no substitution for seat time. Here at Summit Point there is a little old lady in a barely turbo'ed Miata that I can never touch, she simply runs away from me...

Just my 2 cents..

 

[stevbd]

I had the Vorshlag streetpro setup on my car for 80K miles and recently switched to the Cortex koni 400/200 coilovers. IMO advantages of each:

Vorshlag - Bilsteins probably higher quality than Konis??, monotube front and rear shocks (Cortex monotube rear only), cheaper, I like the Vorshlag cc plates better than GC plates that Cortex uses.

Cortex - height and damping adjustability, shock damping feels better matched to springs, rides better on rough pavement.

On track my lap times have been pretty similar between the two. You can go pretty fast on just basic springs, good dampers, cc plates and big tires.

The 19x11 and 305/30/19 fit fine square with either setup. Personally I wouldn't run 305 daily driving but that's just personal opinion. Yes, you use a 25 mm spacer with the Vorshlag kit and can go a little smaller with the Cortex. Rear springs are inverted on the Cortex so no issue fitting big rims and tires.

I started this other thread comparing rear axle daily ride and handling between the two, you might find it useful: https://trackmustangsonline.com/threads/true-rear-coilover-daily-ride-and-handling-comparison.16874/

Good luck!

 

[blacksheep-1]

A Watts huh...

 

[08Racecraft420S]

A Watts huh...

As of yesterday, I’ve read how controversial they are. Please tell me your reservations on the Watts link lol

 

[blacksheep-1]

As of yesterday, I’ve read how controversial they are. Please tell me your reservations on the Watts link

That's a sticky around here someplace. To put it simply, I just don't think they're necessary. I'd be letting all of TMO down if I didn't say something.

In any case, those Salleens were pretty well sorted out, I'm not sure that I'd make a lot of changes to it.
I'm also not a fan of coil overs for street cars, but I'm a pretty conservative person.

 

[08Racecraft420S]

That's a sticky around here someplace. To put it simply, I just don't think they're necessary. I'd be letting all of TMO down if I didn't say something.

In any case, those Salleens were pretty well sorted out, I'm not sure that I'd make a lot of changes to it.
I'm also not a fan of coil overs for street cars, but I'm a pretty conservative person.

Well to be fair, I did not put the Watts link on it lol. I purchased it that way. So unnecessary or not, it’s on there and I plan to leave it until absolutely necessary to go with something else.

And yeah, it is miles better than a same year regular GT, but I just can’t leave well enough alone. I just don’t have it in me

 

[blacksheep-1]

Well to be fair, I did not put the Watts link on it lol. I purchased it that way. So unnecessary or not, it’s on there and I plan to leave it until absolutely necessary to go with something else.

And yeah, it is miles better than a same year regular GT, but I just can’t leave well enough alone. I just don’t have it in me

Well modifying your car is part of the fun.
I would look at some of the competition cars on here and maybe just copy what they are doing. You can definitely waste a lot of money trying to reinvent the wheel, and the S197 platform is very well developed.
If you start tracking your car a lot, you'll prolly want to look into 18 in wheels at some point. Plenty of race take offs out there in that size.

 

[cgornowich]

Since my car is practically identical to yours, I can share what I believe were the best improvements that worked for me:
1. Brake upgrade - The four piston Brembos with decent pads and a some cooling ducts should be required. Heck, it should have come stock with this set up.
2. Decent shoes - lots of opinions here, I like RE-71's.
3. Oil cooler - again lots of options, but one is required for a supercharged GT that has none stock.
4. Aftermarket shifter - mine would stick in 3rd when at the track. I finally got tired and replaced the whole trans with a Tremec Magnum, it's fun but a shifter upgrade will alleviate the "stuck in 3rd" just fine.

After that, the sky's the limit and the returns are incremental.

I like my torque arm, not for traction (that car just won't hook-up), but it keeps the nose from diving under hard braking. I've learned the trick is to figure out what you think your car is doing badly and address that individual issue. Simply chasing parts upgrades will drive you insane and spend all your money...

Talk soon.

 

[Bill Pemberton]

cgornowich really is in a unique position , since he has a twin to your car and his suggestion is to leave things alone , at least at first. Looking at your car ( beautiful color ) and reading your initial post , you said you planned on going with 19x11s and frankly since the single best improvement to go faster is tires, why not just put some sticky rubber donuts on your beast and figured how it handles from there. I would probably suggest you go for an 18x11 first for more tire choices along with a gearing advantage in my personal opinion ( funny how racing Mustangs were always on 18s ). Good solid race pads, Vorshlag or MMs Camber plates, Apex 18x11s with something like BFG Rival S 1.5s or Falken R660s and you will be amazed at the cornering of your Stang. Save your suspension changes till you get more seat time and let the rubber do your work for you now.

 

[Bill Pemberton]

By the way , Blacksheep 1's feelings on a Watts Link are as follows;
1. They suck.
2. Watts link, what link, no link.
3. They really suck.
4. Like Darwin, they are the missing link , as long as they are missing , you are showing superior intellect.
5. They really, really, really suck.
6. All of the above.

 

[08Racecraft420S]

Since my car is practically identical to yours, I can share what I believe were the best improvements that worked for me:
1. Brake upgrade - The four piston Brembos with decent pads and a some cooling ducts should be required. Heck, it should have come stock with this set up.
2. Decent shoes - lots of opinions here, I like RE-71's.
3. Oil cooler - again lots of options, but one is required for a supercharged GT that has none stock.
4. Aftermarket shifter - mine would stick in 3rd when at the track. I finally got tired and replaced the whole trans with a Tremec Magnum, it's fun but a shifter upgrade will alleviate the "stuck in 3rd" just fine.

After that, the sky's the limit and the returns are incremental.

I like my torque arm, not for traction (that car just won't hook-up), but it keeps the nose from diving under hard braking. I've learned the trick is to figure out what you think your car is doing badly and address that individual issue. Simply chasing parts upgrades will drive you insane and spend all your money...

Talk soon.

Thanks for the recommendations!
1. The car already has front Saleen/Stoptech four pistons and stainless lines as well as the JLT brake cooling duct kit. I also will be upgrading the rears to 13/14 GT500 rotors and will be getting better pads all the way around.
2. For my purposes, I will probably go with something a bit less aggressive. Probably the Continental Extreme Contacts in 305/30/19's. Car already has 3.73's as well and at its power level, a slightly taller tire wouldn't hurt. Maybe if I get more into track day events I'll get a second set of wheels in 18x11 with some sure enough sticky tires to swap on for the event.
3. Definitely plan on doing this on top of other cooling mods like larger radiator, GT500 electric fan, larger heat exchanger, 160-170 degree thermostat, and upgraded intercooler pump.
4. Yes this factory shifter sucks. I plan on swapping in a MT82 with Exedy Mach 500 clutch, stainless clutch line, and MGW or Barton shifter. I've had two S550 GT's and love the MT82 gear ratios.

As far as the Watts Link goes.... it's staying since I didn't pay anything for it.

Thanks to everyone else for the help. Already ordered the entry level Cortex Xtreme-Grip kit with Koni internals and street valving option and will also be getting their LCA kit and 18mm rear bar.

 

[gwilliams38]

Thanks for the recommendations!
1. The car already has front Saleen/Stoptech four pistons and stainless lines as well as the JLT brake cooling duct kit. I also will be upgrading the rears to 13/14 GT500 rotors and will be getting better pads all the way around.
2. For my purposes, I will probably go with something a bit less aggressive. Probably the Continental Extreme Contacts in 305/30/19's. Car already has 3.73's as well and at its power level, a slightly taller tire wouldn't hurt. Maybe if I get more into track day events I'll get a second set of wheels in 18x11 with some sure enough sticky tires to swap on for the event.
3. Definitely plan on doing this on top of other cooling mods like larger radiator, GT500 electric fan, larger heat exchanger, 160-170 degree thermostat, and upgraded intercooler pump.
4. Yes this factory shifter sucks. I plan on swapping in a MT82 with Exedy Mach 500 clutch, stainless clutch line, and MGW or Barton shifter. I've had two S550 GT's and love the MT82 gear ratios.

As far as the Watts Link goes.... it's staying since I didn't pay anything for it.

Thanks to everyone else for the help. Already ordered the entry level Cortex Xtreme-Grip kit with Koni internals and street valving option and will also be getting their LCA kit and 18mm rear bar.

If you've had the S550s then you know the MT-82 so I will assume you are talking about a built MT-82. Yours is a very cool project, muy jealous. Enjoy

 

[08Racecraft420S]

If you've had the S550s then you know the MT-82 so I will assume you are talking about a built MT-82. Yours is a very cool project, muy jealous. Enjoy

I'm excited to really get going on it!

And honestly, no lol. My experience with a "built" MT82 was worse than it was with factory stock MT82's and the built one came from the "MT82 guru" that everyone recommends lol. It will however be a low mileage unit from a 15-17 as Ford seemed to add updates (in the background) every year since they introduced the MT82 in 2011. But you're right in thinking it is really luck of the draw with them as far as getting one that will hold up or not, but thankfully they're relatively inexpensive and plentiful on the used market.