Best ifs kit? rms, hdk, gt suspension, or magnum force?

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Ideally, you would design the set up differently for every build based on the vehicles specific ride height.....just not practical

Or...have one ride height spec for the suspension specs.....like the factory. But then it is "one size fits all"

The compromise for me are the different models of k frames based on the builders ride height expectations I move the LCA pivot....along with everything else in 1/2" increments.

Luckily....most fit within a standard 1" range....but the slammer models are moved significantly.

You are very astute.
 
Also, don't you always want the lower pivot points level, because if you're changing that angle, you effectively change weather or not you have camber gain during body roll

IMO....not necessarily. Ideally, I would prefer a little downward (out from in) angle.

Using the factory UCA attaching points, frame rails, and our motor location pigeon holes what we can do.
 
I am very thorough, I'll say that, I was just curious, because I know bill from rms modifies his spindles for that exact reason, bump steer, although I'm sure it's fine, I just don't like the idea of welding to forged steel, you really have to be careful pre heating and post heating to prevent the weld from becoming brittle, I did talk to him and he said he does offer a brake kit that has a 58.5 hub to hub, with 5.5 inches of travel at the wheel, and I've read the gt suspension has a 58.5, with 6.25 inches at the wheel, so many options out there!
 
The early k's I did all had modified spindles....I still have a pair on the shelf. You are partially right on why the others modify the spindle.....with their lay out....they have to or it wouldn't even be close.

Then I asked myself....why don't all the other street rod style/coilovers hot rods I see not modify the spindles?......so a new approach was looked at and adjusted accordingly .

On claims of others (not RMS) regarding track width / suspension travel ?......I have heard the claim.....but yet to see it. From the pictures posted of that package...58.5 track width?.... 6.25" suspension travel?...... (IMO) mission impossible.
 
I'll do some digging on that,I assume you're talking about the gt package, I seen a video on fb I believe of someone that had one, can't remember what brakes he's running, but he did indeed have a 58.5 hub to hub, with the travel, I believe his is adjustable like you run, which seems a lot easier to run a threaded adjustable bushing like most uppers now run, I'm guessing it makes fabrication a lot more forgiving. I have read and seen great reviews, but I have with every other setup as well......expect magnum force, a lot of bad, and horrible customer service. So I've eliminated them, and their price is outrageous! Hopefully I get a new phone next week and I can give you a call denny, my speaker decided it would be a great time to take a crap, so I'm dealing with social media now:/, I'm over it already! Haha
 
On claims of others (not RMS) regarding track width / suspension travel ?......I have heard the claim.....but yet to see it. From the pictures posted of that package...58.5 track width?.... 6.25" suspension travel?...... (IMO) mission impossible.

Denny. I need to get some new pics up for everyone to see. I've got mine mock installed, waiting on the cam bolts to come in still so I'm just using 2 standard bolts to hold the UCA on and can't adjust anything yet. However, I did measure mine where I have it set now, it's at 59 inches and there's easily another quarter inch of adjustment on each side, so I can easily see it getting down to 58.5, maybe even a tad shorter yet.

As for suspension travel, I'll measure my GTS for you if you want too. I do know the coil over is just shy of 16 inches fully extended with a just shy of 5 inch stroke. Also, I was at the nationals where Carl had his set up, he fully compressed and worked everything to show me and anyone else who was interested how it traveled. I know while i was there, a guy asked to measure it, he did, I don't recall the exact number, but it was over 6 inches.

Although I do want to point something out. I was shopping for brake kits, wilwood, ebay, baer etc. Almost 75% or more of the kits I've looked at for brakes say that the mustang ii hub and rotor add anywhere from .5 to .78 of an inch per side to the track width. Now Wilwood makes some of their kits with an offset hub to compensate for that addition. Is that something anyone else has run into ?
 
I asked this in another thread but it probably fits here better than there, since we are comparing the kits.

Denny,

I'm curious for comparison sake, what are the bump steer specs for your kit ?
 
I called Denny this morning to clarify the track width measurement criteria. He said that the HDK's 58" "hub-to-hub" measurement is at ride height (not control arms drooped) from the outside of the wheel mounting surface after the rotors are installed - Not from the spindle hub surface.

If you don't have the rotors on yet, then the measurement is being made from the wrong place. Does anybody have a good measurement from the GST or any of the other brands that has been taken in this fashion? Please let us know what it is.
 
Yes, the video I seen was with the lower control arm level, upper control arm inclined up from the frame to the spindle, with the brakes on, as far as I know I've never even heard of someone NOT measuring to the actual hub (where the back of the rim would seat) rms offers a brakes package that gives you 58.5 rotor hub to rotor hub just to be clear, as well, but 90% of it boils down to what brakes your using from my research, some add .75 per side, so regardless of whose k frame you buy, who have to get the proper brakes to accommodate your desired track width, in essence if you set dennys setup to 58 with brand X brakes, then change brakes later, you could possibly end up with a 59.5 hub to hub by simply putting on a different set of brakes
 
So I guess what it boils down to is what brake package is rms, hdk, and gts using to get their hub to hub distance, that's what I'm starting to gather, I'm guessing the cheaper the brakes, the wider, (to an extent) your hub to hub is.
 
I will say, Dennys design is very nice, I know rms has been around the longest, and been time tested, gts looks very nice, and very strong, magnum force.....well, it looks like a jungle
 
I called Denny this morning to clarify the track width measurement criteria. He said that the HDK's 58" "hub-to-hub" measurement is at ride height (not control arms drooped) from the outside of the wheel mounting surface after the rotors are installed - Not from the spindle hub surface.

If you don't have the rotors on yet, then the measurement is being made from the wrong place. Does anybody have a good measurement from the GST or any of the other brands that has been taken in this fashion? Please let us know what it is.


I understand this. When I set mine, because I didn't have the rotors or the wheels and tires I'm going to run, I simply used some jacks, made the lower control arms level(i used a laser level to verify they were level btw), bolted on a pair of Mustang II hubs I had laying around from a previous project that used a 2 piece hub/rotor and took a measurement with a tap measure from the front face of the hub to front face of the hub, which is where the rim mounts.

This why I brought up the point about the hubs adding to the width. Because I would think it would depend ultimately on the hub used to get the right width.

Not only that, but most coil overs are adjustable as far as ride height at least an inch or so in either direction. Adjusting the ride height is going to change the angle of the LCAs slightly to some degree, thus slightly moving the angle of the hub up or down which, if I'm not mistaken, would alter the distance between the 2 hub faces, would it not?
 
If you don't have the rotors on yet, then the measurement is being made from the wrong place. Does anybody have a good measurement from the GST or any of the other brands that has been taken in this fashion? Please let us know what it is.

Again, I think this is gonna really depending on the type of brakes used. let me break it down for you:

You have 2 kits, say both are at 60 inches hub face to hub face (using stock style hubs)

Kit A:
Used brakes and hubs that add .75 inches to each side from a stock hub style for a total gain of 1.5 inches, you are now at 61.5 inches hub face to hub face, where the rim mounts

Kit B: Exact same kit, same builder. However this one uses brakes that use an offset hub (wilwood narrow 6Rs specs), bringing the hub back to a 0 inch gain. You still have a 60 inch track width.


Now where it really gets interesting is I've found there are kits that actually have hubs that are negative on offset and thus narrows the track width, wilwood actually advertises them on their web site.

Regardless, there are a lot of brake kits out there from various manufacturers, some list the track width gain or loss and others don't. So unless we know that offset number, we can't accurately say one kit is narrow or wider than the other.
 
Again, I think this is gonna really depending on the type of brakes used. let me break it down for you:

You have 2 kits, say both are at 60 inches hub face to hub face (using stock style hubs)

Kit A:
Used brakes and hubs that add .75 inches to each side from a stock hub style for a total gain of 1.5 inches, you are now at 61.5 inches hub face to hub face, where the rim mounts

Kit B: Exact same kit, same builder. However this one uses brakes that use an offset hub (wilwood narrow 6Rs specs), bringing the hub back to a 0 inch gain. You still have a 60 inch track width.


Now where it really gets interesting is I've found there are kits that actually have hubs that are negative on offset and thus narrows the track width, wilwood actually advertises them on their web site.

Regardless, there are a lot of brake kits out there from various manufacturers, some list the track width gain or loss and others don't. So unless we know that offset number, we can't accurately say one kit is narrow or wider than the other.

And let me throw another scenario out there. Lets say i bought a set of brakes that add 0 inches per side, they are stock style brakes but a year from now I decide to upgrade to 14 inch rotors that add a .75 inch per side, now the rims and tires I was running may rub, because the extra .75 inch per hub is moving the tire and rim out .75 inch.
 
I am no fan of IFS on any of these cars, because the factory Mopar suspension can do a LOT like it is, if everything is in good condition and set up correctly.

That said, if I were to go with one, it would be the HDK. None of the others you mentioned has representatives on this site.....or if they do, they are non participants.

With the HDK system, you have the owner hisself right here on forum who participates on a REAL regular basis to answer questions and provide help if needed. Customer service would be my first concern and Denny has that covered, not to mention he builds a nice product.

That should mean a lot coming from someone who'll probably never use one.
 
I am no fan of IFS on any of these cars, because the factory Mopar suspension can do a LOT like it is, if everything is in good condition and set up correctly.

That said, if I were to go with one, it would be the HDK. None of the others you mentioned has representatives on this site.....or if they do, they are non participants.

With the HDK system, you have the owner hisself right here on forum who participates on a REAL regular basis to answer questions and provide help if needed. Customer service would be my first concern and Denny has that covered, not to mention he builds a nice product.

That should mean a lot coming from someone who'll probably never use one.

Thanks for the vote of confidence RRR.
 
I have used the "budget conscious" eBay special brakes....and the Wilwood brakes.....all have been within .010 (nominal) on moving the hub.....most make no change whatsoever. The only ones that pushed the hub out were a set of ancient Wilwoods salvaged off a Magnum Force K setup.

I have also swapped the Wilwood Pro spindle for the eBay special......both put the face of the spindle in the same spot....as they should

Nothing wrong with either.....you get what you pay for.

In comparing the HDK UCAs with the ones from the other K-frame brands......from what I am seeing, the HDK UCA's appear to be much shorter than any of the others on the market. Combined with the HDK upper shock mount and chromoly supports, these components allow for the narrower track width. Since we all use the same factory UCA attaching / mounting points.....I struggle with the idea of a much longer UCA being able to achieve the same 58" track width......but I have been wrong more than once. Ask my wife.

Upon request, HDK supplied upper shock mounts and support hoops to a quality builder that already had an RMS suspension that he loved but he was tired of catching his fender lip and wanted to pull the tires in farther. He cut off the RMS upper shock mounts and took over an inch off of all four control arms. Mission accomplished. My point is, with the RMS /Turbofreek style shock mount combined with longer control arm.....I just do not see how anything under 60" wide is possible.

Just shop talk.
 
I have used the "budget conscious " e-bay special brakes....and Wildwood brakes.....all have been within .010 (nominal) on moving the hub.....most make no change what so ever.The only ones that pushed the hub out were a set of ancient Wilwoods salvaged off a Magnum Force K

I have also swapped the Wildwood Pro spindle for the e bay special......both put the face of the spindle in the same spot....as they should

Nothing wrong with either.....you get what you pay for.

In comparing UCAs with others ....from what I am seeing, the HDK appears much shorter than any other on the market. Combined with the upper shock mount and chromoly supports, these components allows the narrow track width. Since we all use the same factory attaching / mounting points.....I struggle with a much longer UCA being able to achieve the same 58" track width......but I have been wrong more than once. Ask my wife.

Upon request, HDK supplied the shock mounts and support hoops to a quality builder that had a RMS. He loved it, but was tired of catching his fender lip and wanted to pull the tires in. , He cut off the RMS shock mounts and took over an inch off the control arms.Mission accomplished. My point is, with the RMS /Turbofreek style shock mount combined with longer control arm.....I just do not see how anything under 60" is possible.

I think RMS pull their hub inward by utilizing their torsion bar k.....like in Charneys BEAUTIFUL AND FAST Dart.

Just shop talk.



As I'm very impressed with your setup denny, you are wrong on the brakes, wilwoods site clearly shows that, however I have seen benefits to every setup, and downs to every setup, I have to say it's between you and gt suspension, I'm curious if you can give me some numbers, as far as bump steer per inch of travel, camber gain, and lateral gforce your setup can handle, I'm also curious to how wide your lca's are, they look narrower than the uppers are, (from pictures I've seen) than the uppers, I'm sure it works great, just wondering, and what do you run for caster/camber/toe, this will be for an a body street car, sitting at stock ride hieght. Thanks!
 
you mean my wife is right AGAIN!!!

maybe we are not using the same packages???
140-9917D (4-piston).....plus .010...(nominal)
140-11017D (4-piston)....zero offset
140-10741D (6-piston)....plus .010 ....(nominal)
these are the packages I use and recommmend

which one are you looking at?
 
I recommend the same specs as others using the Mustang II front, however, some like to get a little more aggressive on the caster.

I live in flat NW Ohio....hardly any curves so I run closer to a drag set up with very little negative camber....both the same....negative 1/4 degree on each side

caster (mine is manual) 3.5 degrees positive
for power....up to 6 degrees positive (some are running this with manual and love it)

1/32" toe in

some like an extra 1/4 degree (camber) on the pass (right) side
 
Denny
I just want to know your system will be able to suit a slant 6 with mounts to your system? I am looking to put your system in and then add turbo to my slant 6 afterwards. I am looking to purchase just after the new year and may just come up from Nashville, TN to have you install too.
 
Denny
I just want to know your system will be able to suit a slant 6 with mounts to your system? I am looking to put your system in and then add turbo to my slant 6 afterwards. I am looking to purchase just after the new year and may just come up from Nashville, TN to have you install too.

I talked to Mike Schumaker / Schumacher Creative Services about mounts a few months back....he said he will have mounts ready this winter.

I'm in!!
 
you mean my wife is right AGAIN!!!

maybe we are not using the same packages???
140-9917D (4-piston).....plus .010...(nominal)
140-11017D (4-piston)....zero offset
140-10741D (6-piston)....plus .010 ....(nominal)
these are the packages I use and recommmend

which one are you looking at?

140-2275(+.55)
140-9801D (+.68 )

speedway kit 91031944(+.5)
 
140-2275(+.55)
140-9801D (+.68)

speedway kit 91031944(+.5)

Never used any of them....I see why.

I went to great pains to get the wheels tucked and once I started using the Wilwood and the ecos...like the ECI kit.....I quit looking.
 
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