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Kenny Brown AGS 4.5: Have I Been Living Under A rock Or Is This Brand New?

38
14
CA
As the thread title reads.....

Either KB needs a better marketing group, or this just recently came out. Know anybody who's running it? Hard to justify 2x the price compared to cortex TQ arm and watts, but it is interesting. Haven't had an opportunity to really dive into the tech of it.

 
592
167
I don't even own a Boss 302 any more but I want to buy that thing and hang it on a wall! What a beautiful piece and some interesting science there.
 

Grant 302

basic and well known psychic
News to me…but I’ve been under the proverbial rock. Well, as far as Mustang stuff anyway.
In principle, I think this K system should eliminate or seriously reduce misc issues in the right vs left differences in either panhard or watts.
Glad somebody is actually developing new stuff for these old ponies.
 

Mad Hatter

Gotta go Faster
4,001
2,502
Santiago, Chile
What bad things have you heard?

I know the KB s197 K-members were problematic, but apparently they have been re-designed to directly address the previous issues.
Mainly about the K members. But more too the point, would like to see how does on the track. Its been ages since the name Kenny Brown has showed here. It would be great for everybody if they joined TMO!
 
4,433
4,191
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Its been around for a while, just under wraps.
I don't think he was ready for a public reveal just yet, those of us who knew many months ago were sworn to secrecy.
The point of this suspension is to lower the rear roll center to near ground level, which effectively decouples the body roll from axle roll so the rear tires stay on the ground for increased traction. The down side is excessive body roll and severe understeer which he combats with very high spring rates. Reports are very promising. There was one at Sonoma during a practice session I was in and while it was fast, it pushed like a tug boat. Kenny talks about how they cured it with #600 rear springs. (no rear sway bar) Seems odd to me to make a bunch of traction and then throw some of it away with excessive spring rate but what do I know. It will be interesting to see how this all plays out.
 
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Mad Hatter

Gotta go Faster
4,001
2,502
Santiago, Chile
Its been around for a while, just under wraps.
I don't think he was ready for a public reveal just yet, those of us who knew many months ago were sworn to secrecy.
The point of this suspension is to lower the rear roll center to near ground level, which effectively decouples the body roll from axle roll so the rear tires stay on the ground for increased traction. The down side is excessive body roll and severe understeer which he combats with very high spring rates. Reports are very promising. There was one at Sonoma during a practice session I was in and while it was fast, it pushed like a tug boat. Kenny talks about how they cured it with #600 rear springs. Seems odd to me to make a bunch of traction and then throw some of it away with excessive spring rate but what do I know. It will be interesting to see how this all plays out.
Interesting, the proof will be in the pudding!
 
38
14
CA
That direct link was meant for a limited audience.
Notice that this product does not show on the website under "s197 suspension."
It's funny you mention that, when I clicked "S197" under their website, it didn't come up. But then I clicked the "rear grip kit" (the normal one with the PHB relocation bracket), and then this AGS 4.5 kit popped up at the bottom of the screen in the "recommended products" tab. It felt like I found it by accident.

I hope I haven't screwed up their reveal or anything. If I have feel free to take this post down. I just saw it and obviously was pretty surprised, I had never heard of it before.

Excessive understeer could be combated by running thicker rear sway bar, excessive body roll could be tuned out with springs, no?

Hopefully they will do a more proper reveal and have recommended spring rates to go along with this new "K-Link".
 
4,433
4,191
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
It's funny you mention that, when I clicked "S197" under their website, it didn't come up. But then I clicked the "rear grip kit" (the normal one with the PHB relocation bracket), and then this AGS 4.5 kit popped up at the bottom of the screen in the "recommended products" tab. It felt like I found it by accident.

I hope I haven't screwed up their reveal or anything. If I have feel free to take this post down. I just saw it and obviously was pretty surprised, I had never heard of it before.

Excessive understeer could be combated by running thicker rear sway bar, excessive body roll could be tuned out with springs, no?

Hopefully they will do a more proper reveal and have recommended spring rates to go along with this new "K-Link".
Its possible that its a marketing strategy to generate interest. But that's just a guess.
Kenny doesn't use rear sway bars. Yes, he is tuning it with heavy springs. Very heavy.
There are lots of different setup strategy's out there. Time will tell how this one plays out.
Might be the coolest thing in the world....might be a gimmicky contraption. We shall see.
 
38
14
CA
Kenny actually didn't invent it, the basic concept was in an ancient engineering book he came across decades ago and liked the idea and developed it for the s197.
So do you think the main advantage to K-Link compared to tq arm+watts is just the lower rear roll center?

Is there any significant difference to the fact that the K-link doesn't mount to the diff housing but instead is separate? (ie comparing to a watts link diff cover)
 
4,433
4,191
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
So do you think the main advantage to K-Link compared to tq arm+watts is just the lower rear roll center?

Is there any significant difference to the fact that the K-link doesn't mount to the diff housing but instead is separate? (ie comparing to a watts link diff cover)
Kenny doesn't like torque arms.
The whole point is to get the roll center as low as possible. The lower the better and then tune out the negative aspects. That's the whole strategy. You can't get a watts or pan hard bar this low so this contraption is his answer.
 
4,433
4,191
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
It's funny you mention that, when I clicked "S197" under their website, it didn't come up. But then I clicked the "rear grip kit" (the normal one with the PHB relocation bracket), and then this AGS 4.5 kit popped up at the bottom of the screen in the "recommended products" tab. It felt like I found it by accident.

I hope I haven't screwed up their reveal or anything. If I have feel free to take this post down. I just saw it and obviously was pretty surprised, I had never heard of it before.

Excessive understeer could be combated by running thicker rear sway bar, excessive body roll could be tuned out with springs, no?

Hopefully they will do a more proper reveal and have recommended spring rates to go along with this new "K-Link".
They must have caught that because it no longer shows at the bottom like that.
 
72
79
Exp. Type
HPDE
MN
I have a friend from IL that runs this in his 2013/14 track car. He did the install last winter and the debut at RA in the spring was uneventful, but I also think he was relearning the car as well. He' s a fan of KB and I believe got the 1st one produced. We haven't touched base since July, but I'm assuming he ran it all season.
 

Dave_W

Cones - not just for ice cream
411
395
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
The big claim to fame of the Mumford link is the ability to get the roll center on a solid axle car lower than can be achieved with either a Panhard or Watts setup. The RC is the point the 2 axle-to-pivot arms intersect. http://www.bevenyoung.com.au/mumford.html

Take a look at this video and the change in distance from the car body to the Watts axle-side pivot (which defines the roll center) on track.
Then check out how much the Mumford's roll center moves in this video and imagine what it would be doing in that track video.
Granted, it's an extreme example, and possibly with different link dimensions the migration may be less, but reducing that RC migration could be a reason why one would want to use super-stiff springs to limit the dive/squat ride height changes. Note that KB is selling the Mumford link in a package with what looks like all 3 trailing arm mounts, which may be designed to also change the anti-squat to reduce the RC migration.

I think how low you want the rear RC is highly dependent on where the front RC is. Common wisdom is that you want the rear RC a bit higher than the front RC to create slight steady-state understeer. I haven't done it, but I'm sure there are members who've done the front RC calculations for different ride heights. It would be interesting to see how much the front RC moves under dive & squat in relation to the Center of Gravity, and compare that to the rear RC movement for axle-pivot Watts, Panhard bar, & body-pivot Watts. I think I've read that the front RC lowers at a greater rate than the amount the car is lowered. Maybe the Mumford would be beneficial for an extremely lowered Mustang that still uses a McStrut front without extended balljoints.
 

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