Mustang II vs. C6 IFS

[El_Diablo]

I'm in the process of building a slightly more modern interpretation of a pro-touring car with my '95 Mustang. I havesome pretty radical goals for the car but one thing keeps bugging me while I plan out this build.

I currently have a tubular K member with tubular control arms as well as coilovers waiting in my parts rack for this build. My issue is that while that maybe fine for the average mustang guy, I’ve always wanted to go with an SLA setup to really make this thing handle. While all the off the shelf options such as Agent47 are fantastic in what they do, I feel that I may be able to have a better handling setup while being lighter & costing less as well as opening up some better braking options.

My plan is to essentially build a frame for the car and channel the existing "frame" down over top of it (sort of like through the frame sub-frame connectors) which will then become part of the unibody in order to increase strength as well as occupant safety. For the rear I will be using a convertible 3/4 link system but when I get to the front I'm really having a hard time finding the information that I need to make an informed decision on which direction to take. It doesn't seem there have been many comparisons on these two at all.

I would assume that the c6 will handle better but then again, with so many modifications available for the Mustang II is that even close to true? I guess it really comes down to a few questions-

Which handles better (out of the box or modified)?
Which is more tunable to meet my handling needs?
Which has better brake availability (I was going with the GT500 setup & FR500 ABS)?
Which has better geometry or geometry potential?
If it were your vehicle which would you choose and why?

[no go nova]

I think you will be good with bolt on road racing suspension for the sn-95 chassis.

[El_Diablo]

I'm sure it would work with even the stock suspension but I know there are better ways. The stock setup also limits me a bit as far as engine setback & getting the engine nice and low to fully utilize a dry sump setup. The stock front strut towers & inner fenders also limit plumbing for the turbos and other bits.

On the extreme end the car will be capable of producing 1200-1500hp and I would like handling that matches that extreme (though for corners it will usually be left around 600-800hp). I've never really been complacent with "good enough".

[Bryce]

Look up Agent 47

[El_Diablo]

I already did & I'm well aware of them but thank you for the suggestion.

While all the off the shelf options such as Agent47 are fantastic in what they do, I feel that I may be able to have a better handling setup while being lighter & costing less as well as opening up some better braking options.

Really looking towards either the c6 & mustang 2 setup depending on which will perform better and which gives me the most adjustability and brake options. I've already gone over the off the shelf systems many times and have one sitting on one of my parts racks currently.

[Bryce]

I already did & I'm well aware of them but thank you for the suggestion.


Really looking towards either the c6 & mustang 2 setup depending on which will perform better and which gives me the most adjustability and brake options. I've already gone over the off the shelf systems many times and have one sitting on one of my parts racks currently.

HAHA, oops. Thats what I get for ready fast.

MII is junk so anything would be better than that. Just remeber that the C6 was designed for the C6 and the geometry may be comprmoised due to packaging. I would start with a good spindle and design around that spindle and package the best suspension you can.

[El_Diablo]

With the way I'm setting the car up I'm not that concerned with suspension packaging as I am with getting something that will perform. I guess what it comes down to is I can create solutions but I feel I would be safer to adapt rather than to create a whole new system. I can easily get some billet control arms made but if theres an off the shelf solution I believe it would be a much wiser choice for something that I wish to take to track day events that may end up off the track from time to time, lol.

Likely, If I went C6 it would be using Art Morrison's kit.

Why exactly is the MII system junk?

[Bryce]

I do not like the MII because of the really low roll center and the large RC migration. Camber gain and bumpsteer and not ideal either.

[Greg55_99]

Think outside the box. It’s for a truck.

http://www.industrialchassisinc.com/?cat=5

But, if you can get 30” between your frame rails, it could be made to work. There are kits available to upgrade the Dakota stuff to Viper brakes.

Just sayin’….

Greg

[El_Diablo]

Not really liking the truck setup. Does anyone know of any good books to help me figure out suspension geometry and design? Still tempted to use the AM c6 kit just for ease of use. Pretty much any SLA setup will handle better than the strut design currently on my car.

[Rhino]

Given what we have available today I don't know that I'd ever consider a performance oriented MII based suspension on anything other than the MII.

Two of my favorites can usually be found on amazon at pretty low prices:
How to Make Your Car Handle by Puhn, Fred
Chassis Engineering by Adams, Herb

[Schwartz Performance]

Mustang ii's and Pinto's are great handling cars!

Just kidding! Stick with your stock suspension before going to mustang ii :)

Have you looked at Griggs Racing, Maximum Motorsports, or Steeda? They've all got some good stuff available

[El_Diablo]

I highly doubt the M2 is worse than the strut setup on the stock car being that it goes into positive camber, lol. The setup I have currently is very similar to the Maximum Motorsports setup & steeda doesn't even come close to handling like the Maximum setup IMO. Griggs is a fantastic option but very expensive and I would still have to cut the K member up a bit to get the engine set back as far as I'm wanting to.

I love the idea of a simplistic "hot rod" style kit such as the AM c6 kits but if I can engineer or find something that will work better I will.

I think right now I just need to find out what the ideal geometry would be for a car such as mine.

[Greg55_99]

Not really liking the truck setup. Does anyone know of any good books to help me figure out suspension geometry and design? Still tempted to use the AM c6 kit just for ease of use. Pretty much any SLA setup will handle better than the strut design currently on my car.

I see your point. Still, in my Mopar, I'm going with the Industrial Chassis setup.

https://static1.pt-content.com/images/pt/2013/04/7590724Volare_Dak2JPG-1.jpg

https://static1.pt-content.com/images/pt/2013/04/7612853Volare_Dak4-1.jpg

Good geometry. Still working on the install. Tough as nails. Inexpensive ($795). Just sayin'.

Like we used to say, "Roll yer own".

Greg

[Rhino]

Every response thus far has been advising against a MII setup yet you're still contemplating it. Is there a particular reason you're desiring this type of setup?
Before jumping into a decision you're likely to regret take the time to educate yourself on the basics of suspension design. The books I posted previously won't take more than a few weeks to get through and you'll know enough to get started comparing these systems. I'd wager a fair amount that after running the numbers you'll see why the MII is far less than optimal.

There really isn't such a thing as an ideal geometry. You'll always end up with a series of compromises. When designing a system you work toward mitigating those consequences during normal operation.

[RobNoLimit]

Check out AutoWare, and get a copy of 'Suspension Geometry Pro' - it's less than $100 bucks, and it's well worth it. For my next trick, I will place my head gently on the chopping block. Here goes. Both the C6 and M2 have problems. IMHO, one is no better or worse than the other. Here are some thoughts.
1. Spindle Height. With all the talk of tall spindles and ball joints, taller must be better. But, a short spindle reacts faster in degrees per amount of camber increase in inches. A tall spindle is simply a way to manipulate the OE geometry to increase camber gain, but a short spindle with the correct geometry would be better (auto-x and technical sections) - But, a taller spindle can be used to gain stability at higher speeds due to better leverage against tire loading.
2. Steering arms and rack position. C6 stuff is a great design, in a 'vette. But, the steering arm/rack position (with the tie rod end on top) is on the high side. This is fine in a 'vette, where the motor is behind the rack, but in a muscle car or truck, the motor is over the rack. If left in the OE configuration, the rack then forces the motor to be lifted, raising the CG - bad. Yes, the steering arms can be swapped, modified, or custom made, and the rack mounted lower. Many times a 'T-Bird' style rack is used (Flaming River) But care must be used to make sure that the rack throw L/R and the steering arm length will yield the full turn. These changes can and will effect the acreman geometry, be carefull here. Also, longer steering arms can come in contact with deep ofset wheels. - more so when the tie rod end is on the bottom.
3. The hub and bearing. OK, the C6 has a new style hub and bearing assembly, and it is nice. Spindle offset is also a consideration. This is the distance from the hub face back to the spindle axis. Longer or bigger offsets will increase the scrub radius, and require deeper offset wheels to get a balanced feel in the steering.
4. As bigger brakes are available for both I think there even here, but the OE C6 brakes are much better than the M2. OE designed GVW is a concern in context. A mid year mustang will tip the scales at 3500 lbs., the C6 appx 4200lbs, and a V8 M2 appx 3300lbs. If you factor in the % of ft. weight, their all about equal.
Ok, here goes. for a custom fab build, I'd take a look at the AME/Wilwood modular M2 spindle. Also, the spindle taper on these is the same as the chrysler screw-in #k-772 (ball joint) easy to build with, and many upgrade and tuning parts avail from Howe and Afco.

There, I said it, go ahead and lower the blade. :)

[El_Diablo]

Every response thus far has been advising against a MII setup yet you're still contemplating it. Is there a particular reason you're desiring this type of setup?
Before jumping into a decision you're likely to regret take the time to educate yourself on the basics of suspension design. The books I posted previously won't take more than a few weeks to get through and you'll know enough to get started comparing these systems. I'd wager a fair amount that after running the numbers you'll see why the MII is far less than optimal.

There really isn't such a thing as an ideal geometry. You'll always end up with a series of compromises. When designing a system you work toward mitigating those consequences during normal operation.It’s not the M2 setup I’m still contemplating, that idea was quickly killed off, it’s between the C6 IFS or building my own front suspension using my own front control arms and my own geometry.

As far as "ideal geometry" I pretty much just meant like you said, a system with the least amount of compromises for my intended use.

Check out AutoWare, and get a copy of 'Suspension Geometry Pro' - it's less than $100 bucks, and it's well worth it. For my next trick, I will place my head gently on the chopping block. Here goes. Both the C6 and M2 have problems. IMHO, one is no better or worse than the other. Here are some thoughts.
1. Spindle Height. With all the talk of tall spindles and ball joints, taller must be better. But, a short spindle reacts faster in degrees per amount of camber increase in inches. A tall spindle is simply a way to manipulate the OE geometry to increase camber gain, but a short spindle with the correct geometry would be better (auto-x and technical sections) - But, a taller spindle can be used to gain stability at higher speeds due to better leverage against tire loading.
2. Steering arms and rack position. C6 stuff is a great design, in a 'vette. But, the steering arm/rack position (with the tie rod end on top) is on the high side. This is fine in a 'vette, where the motor is behind the rack, but in a muscle car or truck, the motor is over the rack. If left in the OE configuration, the rack then forces the motor to be lifted, raising the CG - bad. Yes, the steering arms can be swapped, modified, or custom made, and the rack mounted lower. Many times a 'T-Bird' style rack is used (Flaming River) But care must be used to make sure that the rack throw L/R and the steering arm length will yield the full turn. These changes can and will effect the acreman geometry, be carefull here. Also, longer steering arms can come in contact with deep ofset wheels. - more so when the tie rod end is on the bottom.
3. The hub and bearing. OK, the C6 has a new style hub and bearing assembly, and it is nice. Spindle offset is also a consideration. This is the distance from the hub face back to the spindle axis. Longer or bigger offsets will increase the scrub radius, and require deeper offset wheels to get a balanced feel in the steering.
4. As bigger brakes are available for both I think there even here, but the OE C6 brakes are much better than the M2. OE designed GVW is a concern in context. A mid year mustang will tip the scales at 3500 lbs., the C6 appx 4200lbs, and a V8 M2 appx 3300lbs. If you factor in the % of ft. weight, their all about equal.
Ok, here goes. for a custom fab build, I'd take a look at the AME/Wilwood modular M2 spindle. Also, the spindle taper on these is the same as the chrysler screw-in #k-772 (ball joint) easy to build with, and many upgrade and tuning parts avail from Howe and Afco.
There, I said it, go ahead and lower the blade. :)Thank you for all of the information you have provided.

As far as the C6, I have the freedom to move the steering rack around quite a bit if needed for proper angles. I will be going with a dry sump and sitting the engine back as far as possible, possibly to the point of firewall modification if it’s enough of a gain to make sense.

I was actually thinking about the Cortex Racing spindles but I'll definitely take a look at the modular M2.

Thanks again for all of the information that you've provided. Designing on road suspensions is still a bit new to me but I can do just about anything else on a vehicle so every bit of information I can gather helps work towards that end goal.

[El_Diablo]

So it looks like the Art Morrison weld in IFS isnt based on a mustang 2 system from what they claim. Does anyone have any details on the AME kit? Any AME weld in IFS users?

[Carl @ Chassisworks]

El Diablo, Sounds like you are at the beginning of a very cool project. For your car, I would call Griggs Racing. They have a vast amount of experience and know how to build the SN95 cars to not only handle but win races.

Keep in mind that building your own suspension is not as simple as plugging some numbers into some software; you also have to BUILD the parts.

Here are some short comings of the systems you reference:
C6 Vette: If you put a coilover on the stock arms the spring rate becomes digressive (lotsa fun to tune on a track car) so you have to build your own custom arms to fix this. Keep in mind that a Corvette is only a few inches from being a mid-engine car so correct rack placement is impossible in any muscle car without modifying the steering arm. The bearings don't last on a track car. Rob has it right; it's only a good suspension out of the box when it's packaged on the original car.

Mustang II: I'm not going to beat a dead horse, everyone already knows M-II is far less than ideal if you want the car to handle. Designed in the late 60s, it's nearly identical to the Pinto. Great suspension if you want your car affiliated with something that was known for spontaneous combustion. Your stock suspension design is vastly superior.

If you're intent on doing something different and custom, we offer a modular front crossmember that utilizes completely proprietary components. It's available with all the same options that are on the front of our gStreet Camaro here: http://www.cachassisworks.com/cac_press_67-69Camaro.html

[El_Diablo]

Griggs simply will not work for what I have in store for this build... I need the clearance that removing the strut towers & stock inner fenders will allow me. I know it’s a bit unorthodox but it will be worth it for what I have planned for this car.

The build is currently waiting on the new FRPP coyote sportsman block which hasn't been released yet (hoping it will be capable of holding atleast 1400hp). The envelope will be pushed with this build and new boundaries will be found. Building parts isn't a problem, in many ways for this build, it is the only solution.

The car is being completely gutted (currently in the process) to be blasted and then powder coated. After this the "frame rails" will be built & fitted out of 2x3 .120 DOM square tubing. I was looking for more of a straight forward approach to the front suspension but if I have to build it all to join a spindle to the chassis so be it. The front cross member will most likely be made much like the AME cross member in order to get the engine nice and low (dry sump) as well as to set it back as far as possible.



Again, I will NOT be using the M2 or C6 setup but I am interested in what AME has based their weld in kit off of since they claim that it is in no way related to an M2 system other than the knuckle.

[Carl @ Chassisworks]

Sounds awesome!

No M2 here either. All mounted to a mandrel bent, 4x2, 120 wall crossmember with machined mounting points.
https://static1.pt-content.com/images/pt/2013/05/CamaroFrontSuspension_front_STR-1.jpg

[El_Diablo]

4x2? I'm assuming you meant 2x3?

[Carl @ Chassisworks]

No, I mean 4x2. Or 2x4 if you prefer.

Here's what our crossmember (http://www.cachassisworks.com/Attachments/DataSheets/7160_DS_WEB.pdf)looks like when equipped with components that lean toward the shiny options list.
https://static1.pt-content.com/images/pt/2013/05/PKG_AARM7160_id-1.jpg

[boodlefoof]

I agree with much of what has already been said.

I haven't mapped C6 bits, but the C5 (if any different) front suspension has some nice characteristics... but the high rack placement can cause packaging difficulties if you don't move the engine way back or pop it up through the hood... I built a custom racecar a few years ago (actually, it isn't quite finished yet) around C5 front suspension components and the engine is set very far back. I'm not terribly familiar with the mid-90s Mustangs, but from what I've seen, space is very limited.

Mustang II has some drawbacks and may not work as well as than the factory suspension you have. My current project uses a Mustang II kit that the prior owner put in. After mapping it and at first thinking it would be OK, I'm now doing a little tinkering with it... repositioning upper arms and moving the rack and outer tie rod end mount points.

Carl - As part of the tinkering I mentioned above, I just received my MII solid rack mounts from you guys (p/n 6108). They are going to be very helpful. The rubber busing and single shear bolt setup that came with the original MII kit (from a different company) just strike me as asking for movement under stress... Quick question if I may though... why is the part of 6108 that slips into the MII rack mount hole only half as long as the hole? Just seemed kind of odd.

[Carl @ Chassisworks]

I agree with much of what has already been said. Carl - As part of the tinkering I mentioned above, I just received my MII solid rack mounts from you guys (p/n 6108). They are going to be very helpful. The rubber busing and single shear bolt setup that came with the original MII kit (from a different company) just strike me as asking for movement under stress... Quick question if I may though... why is the part of 6108 that slips into the MII rack mount hole only half as long as the hole? Just seemed kind of odd.

Hi John,
The extra space accounts for the variance in the mount thickness between different manunfacturers and allows you to keep it tight. They shouldn't be experiencing significant front to back forces; just side to side forces. It also doesn't add weight. Remember, these were originally developed for drag race cars so every once counts, right? ;)

[boodlefoof]

Hi John,
The extra space accounts for the variance in the mount thickness between different manunfacturers and allows you to keep it tight. They shouldn't be experiencing significant front to back forces; just side to side forces. It also doesn't add weight. Remember, these were originally developed for drag race cars so every once counts, right? ;)

Thanks, Carl. I wasn't worried about it because, like you said, the forces are all going to be side to side. It just made me give a "hmmmm..." for a moment as I contemplated whether I had somehow ordered the wrong part number or something... But you're right... shaves a couple of ounces!

[Carl @ Chassisworks]

I'm pretty sure the boss made his first set of those with a stone chisel.

[monteboy84]

I highly doubt the M2 is worse than the strut setup on the stock car being that it goes into positive camber, lol. The setup I have currently is very similar to the Maximum Motorsports setup & steeda doesn't even come close to handling like the Maximum setup IMO. Griggs is a fantastic option but very expensive and I would still have to cut the K member up a bit to get the engine set back as far as I'm wanting to.

I love the idea of a simplistic "hot rod" style kit such as the AM c6 kits but if I can engineer or find something that will work better I will.

I think right now I just need to find out what the ideal geometry would be for a car such as mine.

What's your racing experience with the current suspension, or in general? I really wouldn't advise trying to 'push the envelope' unless you A) Have a lot of money to spend, or B) Do a whole lot of reading and research before spending a dime. The stock suspension, while not earth-shattering, is still superior to a Mustang II, those gained popularity by being a cheap, relatively simple IFS that could be slapped onto street rods for better handling over stock.

The positive camber curve of your stock IFS could be remedied fairly easily with geometry changes. While the C5/C6 front suspensions are excellent on a Corvette, the spindle geometry may or may not lend itself well to working with your car. For example, the steering arm is relatively high on the spindle, so in order to reduce/eliminate bumpsteer, you'll probably need to shove the R&P up into the car a ways, or space the tie rod ends down from the steering arm somehow.

While this isn't rocket science, it is fairly easy to ruin a car by diving in and making drastic changes without doing research and calculations beforehand.

-matt

[Damn True]

Unless you really have your heart set on developing (not the same thing as building) a home-brewed solution I think you'll be money, time and expertise ahead by going with A-47 or Griggs.

[HUSTLESTUFF]

You might look at Coretex Racing. I'm working on an all new suspension using their spindles. Their bearings also last on track. Long way to go though. Kinda in your shoes. Mike