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KB AGS-4 Suspension Install

I'm in the middle of installing the KB AGS-4 Street/Sport suspension:
- KB Roll Center Relocation (they have a new bracket on the drivers side to eliminate the flex).
- KB Street/Sport LCA
- KB LCA brackets
- KB 3d link
- KB K-member
- KB super grip front lower control arms
- KB Extreme Matrix subframe connectors
- KB spec Eibach coil over

The stock LS sway bar interfered with the drivers side RC bracket, so its off the car now. KB recommends either a small dia. rear bar or no bar at all.

Some other mods while the car is apart:
- Chicane23 spec Armando road race oil pan
- Baer front and rear 14" slotted 2-piece rotors
- MM CC plates
- MM bump steer
- Stop Tech brake lines
- ARP wheel studs

r/
Eric
 

Dig-It

Kevin
234
7
VA
I'm in the middle of installing the KB AGS 4.0 also.

Darren: the jacking rails are requied for the extreme matrix braces.

Eric: can you still use the B2 LS lower chassis brace/transmission scoop with the KB k-member? Just going by the pics online, it doesn't look like the two are compatable.

BTW, just the front LCAs and extreme matrix brace with the jacking rails welded in really change the car - it's a lot stiffer and transitions flatter.

Thanks,
Kevin
 
Kevin

No, the LS scoop and cross brace will not bolt up. KB is in the final fit/testing of a revised K-member that is supposed to take some of the flex out. I don't have it yet...will let you know what the new one looks like when it arrives.

What else did you install?

Total time so far to install the 3d link, RC relocation kit, and LCA brackets is about 6.0 hrs...the KB instructions are very accurate. This is with jackstands and a good set of tools...might go quicker if you had a lift.

Darren...no cage or roll bar. Just the jacking rails and matrix brace.

r/
Eric
 

Dig-It

Kevin
234
7
VA
Bummer to hear about the cooling scoop. That's something I'd really like to keep for the track.

The rear UCA, RC relocation and Baer front and rear 14" slotted 2-piece rotors should be going in this week.

Other mods I have are very similar to yours (MM CC plates, Stop Tech brake lines, ARP wheel studs). I'm still on the stock shocks and struts with Steeda's Boss lowering springs though.

BT

"r/" - what branch are you? I'm USN
 
Eric said:
I'm in the middle of installing the KB AGS-4 Street/Sport suspension:
- KB Roll Center Relocation (they have a new bracket on the drivers side to eliminate the flex).
- KB Street/Sport LCA
- KB LCA brackets
- KB 3d link
- KB K-member
- KB super grip front lower control arms
- KB Extreme Matrix subframe connectors
- KB spec Eibach coil over

The stock LS sway bar interfered with the drivers side RC bracket, so its off the car now. KB recommends either a small dia. rear bar or no bar at all.

Some other mods while the car is apart:
- Chicane23 spec Armando road race oil pan
- Baer front and rear 14" slotted 2-piece rotors
- MM CC plates
- MM bump steer
- Stop Tech brake lines
- ARP wheel studs

r/
Eric
Nice. My friend is installing most of that kit but not the coil overs, K member or oil pan. He also has the Baer rotors front and rear. In for updates.
 
Nice setup
How the installation goes? Can you post some pics of the rear LCA with the bracket please?
I've got the the rear LCA + bracket and run into some problem while installing them.
https://trackmustangsonline.com/index.php?topic=4203.0
Did you have the same issue?

Also while tightening everything to torque, the spacer that goes into the original LCA location just "compress" so now it's ~1mm shorter than normal. I will make another one stronger from aluminium and how that goes.
 

Dig-It

Kevin
234
7
VA
Completed the KB AGS 4.0 install (as much as I'm going to do anyway). I'm very happy with how the car handles now.
 
Some updates.

Installed the Kenny Brown Eibach coilovers

DSC01079_zps2f0bbfae.jpg

DSC01077_zpsc062425e.jpg

Ride height at the top of fender lip
Front: 27 1/2"
Rear: 28"

DSC01087_zps790b71cb.jpg

The ride quality is not harsh.

Waiting on the K-Member to finish the front lower control arm and 36mm front sway bar install.

r/
Eric
 
Thanks for the update. That stuff looks great. I'm in full research mode on Kenny Brown, so I appreciate all comments and details. A couple of things:

* Per previous posters question, any unusual gaps between LCA and brackets? If so, how was that resolved? Torque or spacers?

* I have read elsewhere that the roll center relocation kit (RCRK) requires that the vehicle be lowered and that if lowering is not substantial enough, the RCRK might not be able to adjust into the ideal location. Since you only just now added coilovers, what was your experience before? Did you have the RCRK with other lowering springs, and if so, which springs? Any issues?

Again, thanks for any commentary you have. KB charges a premium with no discounts that I can find, so I want to be 100% comfortable (well, maybe 90% ;) ), before I pull the trigger.
 
Jimmy,

So far the install is pretty straight forward...will verify LCA orientation, but with current orientation I haven't experienced any increased NVH. Actually, installing the RCRK reduced NVH when compared to solid bushing MM panhard bar.

I didn't have a problem with a gap between the LCA and bracket. Once torqued to the factory spec (129lbft), that will close any gap.

I ran the RCRK with the stock LS springs and ride height. It makes a difference...the rear end doesn't feel loose under braking prior to corner entry, it corners much flatter. Though KB recommend a small rear bar or no bar, the placement of the RCRK and LCA brackets preclude using a rear bar...so I am not running one.

The KB Eibach coilovers ride very nice...not harsh. Brake dive is noticeably less (similar experience with the folks who've installed "P" springs). The MM CC plates (2011+) bolted right up.

KB is re-designing the K-Member, they are projecting sometime in April to be complete (KB wasn't satisfied with the the 1st prototype so back to design). Once I have that, I'll install the front control arms. The front control arms address dive angle and raise the front roll center.

I haven't installed the matrix braces yet either. Those will address chassis flex.

Dig-It has the AGS-4 installed on his car....he'd be a good one to ask as well.

Finally, John at Chicane23 (Chicane23.com) is a good guy to speak with...they had the AGS-4 installed on their Boss.

All in all, the quality of the parts is top notch. Expensive, yes, but they do race what they sell and have been successful in that regard.

r/
Eric
 
Eric,

Thanks for taking the time to give a detailed response. You have mostly answered my questions and concerns. Just to hit on a couple of points, one of the reasons that I am looking at KB is because they race. Not just support racing, but actually race (and win). Not only does that give me confidence in their R&D, but I also prefer to put my money towards a program that I will not only enjoy as a customer, but also as a race fan.

I also have a philosophy of using as little swaybar as needed and ideally, none at all. Less weight, less complexity. So I like their thinking in that regard.

If I go with the RCRK, it will be with P springs, which are lower than LS. That makes me comfortable that you were able to run the LS/RCRK combo succesfully.

I don't plan to do anything up front right now. Some of that is dictated by budget, but I do like the idea of going in phases. Less is more with me, so the fewer things I feel like I need to do, the happier I am. Also, this is my DD, so I don't want to go cukoo-crazy. Thanks for John's contact info. I'll give him a ring if I think I need another view. Cheers!
 

isrboss

Do you know what changes were made to the Eibach pro street s kit by KB? What spring rates did he use, to require the dampers to be re valved?


Eric said:
Jimmy,

So far the install is pretty straight forward...will verify LCA orientation, but with current orientation I haven't experienced any increased NVH. Actually, installing the RCRK reduced NVH when compared to solid bushing MM panhard bar.

I didn't have a problem with a gap between the LCA and bracket. Once torqued to the factory spec (129lbft), that will close any gap.

I ran the RCRK with the stock LS springs and ride height. It makes a difference...the rear end doesn't feel loose under braking prior to corner entry, it corners much flatter. Though KB recommend a small rear bar or no bar, the placement of the RCRK and LCA brackets preclude using a rear bar...so I am not running one.

The KB Eibach coilovers ride very nice...not harsh. Brake dive is noticeably less (similar experience with the folks who've installed "P" springs). The MM CC plates (2011+) bolted right up.

KB is re-designing the K-Member, they are projecting sometime in April to be complete (KB wasn't satisfied with the the 1st prototype so back to design). Once I have that, I'll install the front control arms. The front control arms address dive angle and raise the front roll center.

I haven't installed the matrix braces yet either. Those will address chassis flex.

Dig-It has the AGS-4 installed on his car....he'd be a good one to ask as well.

Finally, John at Chicane23 (Chicane23.com) is a good guy to speak with...they had the AGS-4 installed on their Boss.

All in all, the quality of the parts is top notch. Expensive, yes, but they do race what they sell and have been successful in that regard.

r/
Eric
 
isrboss said:
Do you know what changes were made to the Eibach pro street s kit by KB? What spring rates did he use, to require the dampers to be re valved?

KB doesn't say, but he does say that he runs higher spring/damping rates than most. He explains his philosophy here:

In all the years I have been building Mustangs I have developed my own set of specifications for making them handle and feel good to drive. From racing we learned that the more spring rate we put into the cars, the better they turn and handle. The same applies to the street, for years I have been running much higher spring rates in my street performance cars than anyone else in the aftermarket.

Now before you say you heard that higher spring rates mean rougher ride; let me put this into perspective. The job of the spring is to support the car whether riding down the street or driving around a corner the job is the same. The more the spring rate the less the car wants to roll going around a turn which means that you can go around the corner faster.

The job of the shock is to dampen, which is why shock absorbers are often referred to as dampers, opposing the forces of the spring and the mass of the car. The higher the spring rate, the better dampening you need for control. Ride quality is a function of the shock valving, bad or worn out shock valving equals bad ride and handling characteristics, good shock valving equals good ride quality and good handling, even with higher rate springs. The high quality of these shocks and the valving inside are equivalent to alternative shocks costing a lot more.
 

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