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Looking to put together a coilover conversion - Koni + MM plates

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I am looking for some help in piecing together a threaded sleeve conversion setup for the front of my car. Goal is to get more spring stiffness and adjustable height, while re-using my existing Koni Sports and Maximum Motorsports C/C plates to minimize incremental investment.

Neither Ground Control nor Maximum Motorsports has a kit to do it (I've called both of them), but it seems like it should be feasible.

Has anyone else been down this path?
 
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I understand what you are trying to do, but I'm not sure it will be worth it in the long run. The ultra hi zoot Penskes are $10K for the set, a decent set of coilovers can be had for about $4 to $5K. They all will have to be rebuilt every 20K miles. I personally prefer using divorced spring and shock systems because in the end, they are much less expensive for the average track guy or daily driver, and except for being able to adjust ride height, the coilovers really don't have a huge advantage, especially when you factor in maintenance. If you must have coilovers I would suggest you call some of the Ford Performance teams out there, Phoenix, Kohr, etc and see what they have that is rebuilt or used before spending the big bucks. IMO trying to get a coilover "kit" to work on standard shocks is getting the worst of both worlds, other than the best, I've done this myself years ago and the results were mediocre at best.
 

Grant 302

basic and well known psychic
Has anyone else been down this path?
I don’t remember anyone here doing it, but I recall there was somebody who made a kit or did the conversions for it a few years back. Also using Koni yellows. I doubt it was all that popular and probably not available anymore.

What spring rates are you planning on?
 
A little more context...I am currently on BMR handling springs at 240 lb/in F and 200 lb/in R. The front spring is a bit too soft (IMO) to control roll on wide RE71's, so I am using more bar than I would prefer to increase roll stiffness (38mm F / 25mm R, both hollow).

I'd like to get the fronts up in the neighborhood of 400-450 lb/in, and likely leave the rears as-is with the current springs. That would let me back off a bit on sway bars to see if it helps the car. The only standard spring I have seen that comes close is the MM, which drops the car another ~0.5". I think the nose is already borderline too low on the BMR springs, so I don't really want to do that.

blacksheep-1, while I completely understand and appreciate your suggestion, I am looking to avoid a big $$$ coilover setup for now. If I can't find a good, less-expensive route to raise the front spring rate, I will likely leave it as-is for now (which honestly isn't bad).
 
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I went with the Ground Control CO setup with race valving and 500/250 springs.I'm also on 19x11 with 305/30/19 PS4.
Great at the track,I had P springs before.Ride is firm but manageable on the street.
It changed the car completely and I'm very happy with the result.
 

Grant 302

basic and well known psychic
I believe you want more spring rate and the height adjustability for the right reasons.

But I gotta wonder if the Koni yellows can appropriately damp the spring rates you want to try up front.
 
So the car won't turn in? is that the problem? or is it strictly that the car rolls too much in the center of the corner?

The main problem is grip at the front. The car is not terrible by any stretch, but I think it could be better. I have to be really deliberate in managing weight transfer--cornering while coasting or trail braking means a pretty healthy push. As soon as I feed in even light throttle, the car is much more balanced and corners really well.
 
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Well, a car that pushes will only get worse as the day goes on, if you loosen up the back of the car so it will rotate, it might solve your problem. I see guys do this all the time, they try to stick the wrong end, and pretty soon you have a car so tight, you can't drive it. Just because you are experiencing a loss of traction in the front, doesn't mean that doing something there is your only alternative. It might be that the suspension is being overwhelmed at some point, and is beyond the design criteria of the car. This happens in production cars all the time. Try going to the rear of the car and set those shocks on a stiffer setting, or add a couple of pounds of air and see what happens.
And yes..I'm going to post this pic again..of a great handling car

qGKqzwcl.jpg
 

Dave_W

Cones - not just for ice cream
984
1,277
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
cornering while coasting or trail braking means a pretty healthy push. As soon as I feed in even light throttle, the car is much more balanced and corners really well.
How lowered is the front? It almost sounds like you're into the bumpstops in the front causing the push; when you accelerate the front shock extension gets off the bumostop and reduces the front wheel rate. You could also have too much front rebound, "jacking down" into the bumpstops.
 

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