AlterKtion - True Pro-Touring Suspension

[Top Heavy]

I am curious as to the ride height and capabilities of the AlterKtion front end suspension/k-member system.

My 1969 Dart will be built as a extremely capable street car, that may/could be involved in track days.

I am VERY interested in the AlterKtion system for the front end, but I am curious as to the available options. The problem with every single tubular coil over package available for Mopar units today is it is a generic replacement, not an intended use built system.

Hopefully if the week slows down fo me I will have a chance to call Bill and have a geometry and purpose discussion for his system, and he may have insight as to my application specifically.

I was looking at possibly going to use the AlterKation complete manual steering package, and removing the spindle, springs, and upper arms when the kit arrived. Then utilizing the Magnumforce 2" lowered spindles, heavier springs on th coil overs, and Hotckis upper arms. Then redrilling the lower arm mounts 1 1/2" higher, and building a 1 1/2" spacer to raise the upper control arm mounts. This type of build may also require the replacement to shorter coil over shocks, as this type of lowering on the supplies coil over could only leave 2" of travel.

This was to be able to correctly lower the front suspension 4" to maintain correct geometry.

Since this the AlterKtion system is a standardized kit, just using a heavier spring and lowering the front end by coil compression height will greatly reduce the effectiveness of the front suspension. This will take the angles of the upper and lower control arms and scew them in relation to each other. This is defiantly not conducive to a "Canyon Carver" suspension.

Has anyone modified the AlterKtion system, or requested the manufacture of a "Pro-Touring" specific front end build?

Any suspension gurus please chime in...............

 

[abodyjoe]

how low do you want the car? call and talk to bill directly before you do any more re-engineering of it in your head. he will be more help then anyone here. and you do know that the alter-k doesn't use a mopar style spindle right? your not going to be able to use a magnumforce spindle with it.

the alter-k was designed for handling in the first place. the drag race thing was just an added bonus with it.

 

[momoparman]

Ditto.

RMS uses Ford mustang spindles which is not a bad thing....they do make 2" drop spindles for mustangs so just ask Bill and he will run through all the do's and donts of the system he engineered. You can do an Air ride system with the AlterK and have the ability to adjust your ride height.

It will save you time and heartache to speak with Bill.

By the way....the RMS system is super sweet. My car handles like it's on rails now.

Mop

 

[autoxcuda]

I am VERY interested in the AlterKtion system for the front end, but I am curious as to the available options. The problem with every single tubular coil over package available for Mopar units today is it is a generic replacement, not an intended use built system.

But what you are proposing to do, removes all of the system built into the Alterkion.

The mods you wanted to do seem like there is a specific geometry you want to run for racing. So you have calc'd all this geometry out, like roll center, roll center movement, camber/caster gain, tire scrub, etc, etc. So now you want someone to build it for you?

I was looking at possibly going to use the AlterKation complete manual steering package, and removing the spindle, springs, and upper arms when the kit arrived. Then utilizing the Magnumforce 2" lowered spindles, heavier springs on th coil overs, and Hotckis upper arms. Then redrilling the lower arm mounts 1 1/2" higher, and building a 1 1/2" spacer to raise the upper control arm mounts. This type of build may also require the replacement to shorter coil over shocks, as this type of lowering on the supplies coil over could only leave 2" of travel.

That sounds like a train wreck.

Figure out what ground clearance you want to run between the alterkion cross member/bar and the pavement. Then figure out what tire size and rim size you want. Only after that, you can figure if the geometry is changed significantly with a call to Bill Reilly.

 

[rjsjea]

I moved my AlterK (coilover version) up into the frame rail two inches...upper control arms mounting points, rack etc. It was a bunch of work and created more work than I thought it would throughout the car.

When it's done though I will have the working ride height I wanted without going to AirRide.

I agree with AutoXcuda's post

 

[1970Duster]

These three guys are giving you the best info you can get (short of talking to Bill himself). Abodyjoe is using alterKtion and streetlynx with coilovers. Momoparman is also using the alterKtion and streetlynx setups both with air ride. Autoxcuda is about the only guy I know that has tried about every suspension setup out there for A bodies, minus the alterKtion and streetlynx setups. I would take their advice and give RMS a call.

 

[autoxcuda]

I moved my AlterK (coilover version) up into the frame rail two inches...upper control arms mounting points, rack etc. It was a bunch of work and created more work than I thought it would throughout the car.

When it's done though I will have the working ride height I wanted without going to AirRide.

I agree with AutoXcuda's post

I thought about suggesting channelling the front end. But that's a big project.

I thought about dropping the center cross member relative to the suspension, but you run into steering linkage to oil pan and frame issues at the least. Not a simple solution.

rjsjea, what is the distance from your bottom front crossmember to the gound at driving around town ride height.

 

[swisswill]

I moved my AlterK (coilover version) up into the frame rail two inches...upper control arms mounting points, rack etc. It was a bunch of work and created more work than I thought it would throughout the car.

When it's done though I will have the working ride height I wanted without going to AirRide.

I agree with AutoXcuda's post

Depending on how low you want to go, this is the way to go. Reason being is it keeps the geometry exactly as it was designed. If you buy an Alter-k, bolt it in then slam it to the ground, the static geometry is different than it was intended to be and there is a "chance" you could be approaching some bind issues on upper ball joint at full compression. If you want it low that isn't a problem, I'm sure Bill has a level of adjustability designed in to compensate a range of ride heights. But if you want it REAL low, you need to set the geometry where it should be, and build around it. In this case, channel the geometry into the existing chassis. I've already been through the suspension geometry design on my build and unless you've got countless hours to put into research (which still won't be enough), best to talk with Bill and see what he recommends.

 

[rjsjea]

rjsjea, what is the distance from your bottom front crossmember to the gound at driving around town ride height.

4 7/8"....puts my coilovers right in the middle of their height setting. The front frame rail where it goes under the floor pan was the lowest point.....so that was sectioned also.

And YES it was a big undertaking mods from front to back of the car....most of my mock-up is done now. This pic is with a mockup set of tire/wheels.....I ended up with a 255 up front for now, makin room for a 275 probably

 

[Top Heavy]

Jrsjea, this is the approximate ride height I am looking for.

The ideal "at rest" would be a clearance of 5" - 5 1/2" from the ground to the bottom of the k-member. With about 3 1/2" - 4" of total suspension travel, meaning 1/2 the distance in either direction from a static position.

There are only a few ways to make this type of set up actually work:

1. Buy a universal kit, measure dozens of times, cut, modify and tack for mock up. Then fully weld as soon as desired geometry and ride height is attained

2. Convince a builder/manufacturer to build a system based on specific parameters, which they more than likely do not have a jig for or they would advertise it.

3. Build from scratch and slowly modify to obtain derided gemoetry.

I am going to start with #2 and call Bill as soon as I hav some time open up, probably going to be next week.

 

[Top Heavy]

Sorry for the short post regarding the desires if the package, but I'm using an iPad not my computer.

Typin on this thing is horrible.

I am experienced enough to tackle any of the 3 options, this will not be a a hack installation. The car is a shell, and will remain so until it is actually ready for the next level.

I will be updating as planing finishes and production begins.

 

[swisswill]

Another option is to contact Art Morrison and have them build you a bikini clip (think that's the name). They can build it to your specs for ride height and for their own Sport IFS, I believe they use the same spindle as Bill. This is a weld-in kit and I believe you can get into it for less than the Alter-k. I've spoken with the engineer at AME many times regarding suspension design and geometry and what they have put together for the Sport IFS is awesome! Download their new catalog and look at pages 37-43, http://artmorrison.com/2006cat/2011catalog.pdf.

Personally I think this is your number 1 and best option.

 

[autoxcuda]

Jrsjea, this is the approximate ride height I am looking for.

The ideal "at rest" would be a clearance of 5" - 5 1/2" from the ground to the bottom of the k-member. With about 3 1/2" - 4" of total suspension travel, meaning 1/2 the distance in either direction from a static position.

There are only a few ways to make this type of set up actually work:

1. Buy a universal kit, measure dozens of times, cut, modify and tack for mock up. Then fully weld as soon as desired geometry and ride height is attained

2. Convince a builder/manufacturer to build a system based on specific parameters, which they more than likely do not have a jig for or they would advertise it.

3. Build from scratch and slowly modify to obtain derided gemoetry.

I am going to start with #2 and call Bill as soon as I hav some time open up, probably going to be next week.

I'm at 5 3/8" to the very bottom-most of the K-member with Hotckis TVS system. Just measured today. I was at 4 1/2" but I needed to raise it for the new TTI headers. At 4 1/2" it scraped once on the bottom of the stock depth trans pan and stock cast iron manifold exhaust pipe on a big parking lot speed bump!

That's with stock chassis pick up points on the chassis; nothing relocated. Now I have 24.5 diameter tires. What size tires are you going to run?

I've heard the Dougs headers give about 1/2"+ more clearance.

IMHO, you are geting to hung up on the geometry after the lowering. No geometry is 100% perfect. There are always compromises. Too many sales pitches and people blabing over the interweb.

 

[jdakota]

Wow. Thanks swisswill. I just downloaded the Art Morrison catalog. He has everything I want in there and I think his prices are pretty good too.

 

[Top Heavy]

I have been combing the web and forums I am a member of, and there are many convoluted threads on suspension theory.

Autoxcuda & Swisswill, thank you for your chime in.

Let's throw out the thought of "Mopar Suspension" specifically for a moment, and make a simple list for a vehicle front suspension. I would like to hear from all of you whom have either built a custom font suspension, bought a custom front suspension, or thinking of one of the previously mentioned options:

1. Need to have

2. Like to have

3. Unreasonable to have


Right now I think the option of the C6 front end looks like a solid option, but ther are trade offs. Excellent rack location, nice long lower arms, BUT a very steep angle on the coil over. It would be nice to see the suspension move and see how effective the angle really is. It would also be good to see a CAD file (which I would doubt anyone would send me), or even a PDF version (which can still be "traced" into CAD), of the side view, front view top view.

Going to a GM based suspension isn't a big deal. GM parts are relatively inexpensive (bearings, brakes, ball joints, etc). I would then order axles drilled to a GM pattern for the rear too.

 

[Top Heavy]

DAMN THE IPAD!

I just lost a few paragraphs, and opted to actually go to my computer now.......

I have spend many hours looking ar reviews, threads, and design of various manufacturers front suspension systems. The cost of Mopar front suspension systems seems to be a touchy subject over all.

For the threads that relate to the cost, regardless of the "supply & demand" model refered to, regardles of the cost, there may very well be someone whom will purchase the said goods at the set rate. We all have a desired rate which we feel is acceptable for certain goods and or services, that rate is very different for all of us. Get over it. If you dont want to pay $5,000 fo Bill's system then don't. If you would prefer to stay with a T-Bar system then do that. If you want to find a "cheaper" system, go ahead.

Personally, I don't feel that $5,000 is unreasonable for a complete suspension package with a high performance braking system. WHat I do feel is unreasonable are companies that try to pass off a suspension system with no R&D, no knowledge or applied experience, and do not have an intended application. To me my life is worth much more than $5,000, and if that what it takes to keep me safe at 150mph, then so be it.

I want the absolute best handling system, which has trade offs in the right areas. This is why I have asked here and on PT.

PS. Sorry if this seems like a rant, I am not angry, I just don't like it when people tell other people what their time or products should cost. I belive in buying North American products, I believe in the "little guy", and I trust a value the input of experienced individuals. Sometimes these things just cost more to have.

 

[Bill_Reilly]

I usually stay out of debates, but I thought it a good idea in this case, to clear up some misconceptions. Top Heavy is right, with bad kits the only design work is the advertisment, and good kits are designed assuming a primary use, compromising other uses for the gains.
I wont talk about others, but I can divulge a few tidbits on the Alterktion...
On the compromises for the design, leaf-sprung drag cars are the ones that have to work on it. We moved the travel range up 1.25", so you lose that much rise when you leave. That drops your 60' time, which requires some adjusting to get it back. 4link and ladder bar cars dont really need the travel and have lots of adjustment available, so there's no concern, but the leaf spring cars have a hard time getting the time back. The other compromise is that 15" rims are limited to 6 inch wide. 17" and up is really what is was intended for, although there are some really nice stock looking customer cars with rally's or painted steel 6" on the front.

Concerning the physical layout, the bad news is that modifiying the system with other spindles and a-arms is impossible without totally butchering everything - all the parts are designed together assuming certain dimensions. Aside from physically mating the parts, deviating from any one dimension would require changing all the other dimensions in order to have even the slightest semblance of decent geometry and/or fitment. Suspension design is typically easy until you try to fit it around an engine.

However, the good news is that I've always worked toward a design that accomodates the use youre looking for. Call it pro-touring or whatever, I always called it a street car that will take corners faster than you have the guts to. If I get scared before the car does, I call it good

Anyway, with a 26" tall front tire and wheel travel centered, you have 5.5" under the crossbar of the kframe, and 7.5" at the rocker panels. The system also has 5.5" of total wheel travel with a track width 0.125" wider than stock discs.
In reality, most of us run with 4.5" under the K frame and 25.5-26" tires, which works best. On a street car, its better to have a bit more rebound travel to suck up the bigger potholes, and you dont want more compression than the car can safely handle - you can channel the suspension up into the car, but the full travel range cant be used because the car hits the pavement before it bottoms. So it's best to design the system where the shock will bottom with the crossbar 2" off the pavement. Even at this point, the exhaust would be scraping. Most of us are running 3" exhaust, and that hangs down a couple inches. Milodon's road race oil pans are above the crossbar, so nothing to worry about there.

In my own car(69 dart/528hemi/6spd), which is currently undergoing it's 3rd redo, I have 5" under the crossbar and 7" under the rocker panels with 25.25" front tire(255/35/18). I also raised the engine and trans 1" higher than stock, which got the big exhaust up close to the floor, but there's still only 3.5" under these big hemi headers. A stiffer compression setting on the shocks will keep it off the ground, and I normally like a stiffer setting anyway, because I beat the beans out of everything...I've had my SRT Charger airborne more than once over railroad tracks and the 4" high front airdam has never touched the ground.

But, if the normal single adjustable QA1 shocks arent enough, we can do doubles, or for the really serious folks, we use custom-made afco shocks, low friction balljoints and very high durometer a-arm bushings.

As for geometry... Bumpsteer is 0.015"/inch of wheel travel. 1.5 degree camber gain with stock upper mounts, ackerman within 2 degrees of ideal at the maximum 18' turning radius. When roll angle and any amount of steering input are combined, roll center migration remains under 1.25". There is 1188lbs of roll resistance per degree of roll but we did it with a smaller bar, so ride quality remains pleasant when you're out on the interstate. Anti-dive is at 49.9% so there's no nose-diving on the brakes, and (assuming my rear suspension for the test), level ground roll rate on a 3200lb car is 1.77 degrees/G - this is with a rear 4-bar suspension with no rear sway bar. Roll center is -1.5" to 2.5", and I'd like that to be a bit higher, which gets me to the next little tidbit of info. At least with our system, lowering the front upper control arm mount 1" increases camber gain to 1 degree per inch of travel, raises the roll center so its in the 1" to 4.75" range, cuts down on caster change. However, it also lowers anti-dive to just 8% and bumpsteer goes up to 0.031"/inch of travel.

I make weld-on upper control arm mounts that can be used to fix or alter stuff, or use the system in a street rod, but I'm not making that change in my own car. The gains and losses are extremely minimal and I'd need stiffer springs to make up for the lost anti-dive, which means a harsher ride quality, so I just decided its not worth doing more work just to say I changed it.
I think I covered all thats been mentioned here, but if not, feel free to ask...

 

[Top Heavy]

Bill, pleased to meet you!

You are speaking my language, and I shall call next week (I hope, depends on how my days unravel).

Might be best To offer my wants vs. needs that way, and you can ask me what you need from me as far as vehicle intentions and surrounding components.

 

[autoxcuda]

... At least with our system, lowering the front upper control arm mount 1" increases camber gain to 1 degree per inch of travel, raises the roll center so its in the 1" to 4.75" range, cuts down on caster change. However, it also lowers anti-dive to just 8% and bumpsteer goes up to 0.031"/inch of travel.

I make weld-on upper control arm mounts that can be used to fix or alter stuff, or use the system in a street rod, but I'm not making that change in my own car. The gains and losses are extremely minimal and I'd need stiffer springs to make up for the lost anti-dive, which means a harsher ride quality, so I just decided its not worth doing more work just to say I changed it.
I think I covered all thats been mentioned here, but if not, feel free to ask...

Thanks for responding. Been a long time!... Amazing what info you can get just asking the product manufacturer rather than assuming or going off what other people say.

If Top Heavy seems to be wanting a serious handling car so his springs should be pretty stiff. .031"/1" bumpsteer is only 1/32" and not that big of deal, IMHO. I'd take the camber gain in roll and higher roll center versus the slight bumpsteer increase...Compromises...

Would you think the loss of anti dive wouldn't be that big of deal with the lowered 1" UCA mount using a stiff spring and good shocks?

Can you fit a 275/40/17 tire on the front of your system with proper rim backspacing. Or a 275/35/18? Does the OTRE interfere with these high backspace rims?

 

[Top Heavy]

As far as front spring rate, based on approximate coil location and materials used for build I have thought around 500-550#.

Unless someone has the front end weight with the follows changes:

1969 Dart (body)

Fiberglass Hood
Fiberglass Fenders
Fiberglass Bumper
Inner Fender Fiberglass (custom)
Front Bracing (triangulated at firewall, in/out)
Tubular front suspension (Bill's of course!)
Manual Rack


383 B engine (500 ci)

M1 Single Plane
Aluminum heads
Aluminum Water Pump
Aluminum Housing
Aluminum Radiator
H/T Mini Starter
Billet Aluminum Pullies

Manual disc brakes

AutoXCuda, Bill, feel free to chime in...........

Springs are quite inexpensive, and can be easily swapped. Most important would be actual shock position and travel...... Which I know you'd have under control.

Wheels. As far as this goes I had hoped for 18x8ish w/ 245-265 for the front and 18x11ish for the rear w/ 325-345........ Wheels will of course be finally selected after suspension is in an body mods are complete. Wheels are Another factor in spring selection......... Which is why "approximate" will have to do until the car is on the road

 

[Top Heavy]

As far as the upper control arm mounts; factory located/installed vs. Modified, if the vehicle is set at 5" ride height at K-Member to mantain correct geometry would the mount not also need to move up 2"?

The upper ball joint would be near binding at rest wouldn't it? Again this is all based on assumption as I would think the UCA would be sitting at the incorrect angle?

Hence my reasoning for wanting to have an actual conversation over the assumption of the system.

 

[swisswill]

Sounds like you just need to call Bill. I think he's open by now.

 

[Bill_Reilly]

Actually, the more I think about it, the more I think anti-dive wouldnt matter much on the street, just because most people dont stress a car enough to matter on a public road.

With a 17" rim, 8" wide/5.70bs is about the limit to clear the tie rod and fender, which I like to mate with a tire less than a 10" section width. So 9.X section is about the widest. On an 18" rim, there's alot more room to the tie rod when turning, so you can go to a 9" rim with around 6.3bs - On an a-body. The B and E cars cant do this because the upper arm is wider and the front a-arm leg hits the 9" rim. On my Dart I'm using the mustang rims - 18X9 in the front, and I did actually fit a 285/35/18 on it. But the tire touched the frame rails by 1/4" when fully turned and it was really close to the fender. So I kept the rim and went down to a 255/35 - I want lots of clearance for those railroad tracks
A 275/35 might not be too bad, but still tight.

And you're right Top Heavy, springs are fairly cheap and easy to swap out on a coil over. Even with lighter springs, the car would be respectable, the heavier springs is getting down to little details and hundreths on a stopwatch. I'd normally go with 450's on your car, but you could do 500's and still be in good shape.
Sounds like a fun car, and there's really only two things I'd mention based on experience/opinion. First, definitely do power rack - the manual racks are ok with drag-type skinnies, but once you have more than 5 or 6" of tread on the ground, it's an absolute bear to steer in parking lots. The power rack also has a better turning radius than manual, which makes a fairly big difference in parking lots.
The other item is informational only, but I had race-weight hood and fenders on my car for years with dzus fasteners all around - they looked awful in the sun because the heat would warp them. I then switched to a heavier bolt-on glass AAR hood and metal fenders - it turned out the weight difference was only 25lbs total and it looked far better. Of course, every pound makes a difference, so thats a personal choice thing.

On the uppers, I make the arms to accomodate the steeper upward angle of the balljoint, so it works fine.
Concerning geometry on the same issue, again, it depends on suspension design. Alot of stock or homemade suspension has poor geometry, so the idea is to level the a-arms and tie rods at ride height(center of the arcs) so you have the most possible travel up and down before the geometry starts to get ugly. Leveling the a-arms is simply the best way to make the most of a bad design. But if the design has favorable angles throughout its travel range, your only concern is to set the desired ride height prior to wheel alignment.

...we can chat on the phone when you like, but I'm happy to keep typing in the meantime

 

[demon34071]

Jrsjea, this is the approximate ride height I am looking for.

The ideal "at rest" would be a clearance of 5" - 5 1/2" from the ground to the bottom of the k-member. With about 3 1/2" - 4" of total suspension travel, meaning 1/2 the distance in either direction from a static position.

There are only a few ways to make this type of set up actually work:

1. Buy a universal kit, measure dozens of times, cut, modify and tack for mock up. Then fully weld as soon as desired geometry and ride height is attained

2. Convince a builder/manufacturer to build a system based on specific parameters, which they more than likely do not have a jig for or they would advertise it.

3. Build from scratch and slowly modify to obtain derided gemoetry.

I am going to start with #2 and call Bill as soon as I hav some time open up, probably going to be next week.

Get in touch with the folks at G-Force as well, they are in PA. They built a Demon with an Alterkation front end and this is about where they ended up to the bottom of the torsion bar cross member (5-5.5"). It puts the bottom of the front frame rail at about 12 - 12.5". I know because I called them for the dimensions to help set up the ride height on the Demon I am building. (Just saving the money for my Alt K set from Bill) Call or email bill as well. I email him monthly with new ideas and plans on the ride height / issues for my 71 Demon with a viper motor mad scientist project... He is extremely helpful!!!

 

[abodyjoe]

[ame="http://www.youtube.com/watch?v=l1RO2OOingI"]YouTube - ‪Dodge DEMON autocross video V8TV‬‏[/ame]

[ame="http://www.youtube.com/watch?v=DnIlun5BQqo&feature=watch_response"]YouTube - ‪1971 Dodge Demon Pro Touring‬‏[/ame]