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Spring Recomendation for Koni Yellows

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Hello everyone, I have Koni yellow's and am currently riding on T-springs. After my last outing this past weekend at VIR I'm starting to think a stiffer spring might be in order. What are you fast guys running? I can't seem to find spring rates for any of the aftermarket springs to see which brands are stiffer and which are softer. I'm running a square setup with a Strano adj. rear bar. Also I assume that progressive vs non progressive will come into play so any knowledge on that would be great too.
 
If you're driving mostly on track look at H&R race springs.
 
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The Maximum Motorsport Road and track springs. Work wonders with the Koni yellows.
http://www.maximummotorsports.com/MM-Road-Track-springs-2005-14-Set-P1445.aspx
 

Grant 302

basic and well known psychic
Personally, I think spring selection is more of a function of tires, weight and suspension geometry which govern the amount of grip available. The Konis can be successfully paired with *any* springs made for this car IMO.

For slicks, it seems the H&R race or MM Road and Track springs could work. I think P springs work great for street tires.
 
Hey dude. Enjoyed suffering through the rainy weekend and the less than perfect instructors with you last weekend.

You want the stiffest springs you can get, short of going coilovers.

Here are the stiffest springs in order.

MM
H&R race
Eibach sportline

There is an additional option that I find interesting, the Ground Control coilover conversion kit designed for Koni Yellows. I have yet to hear a decent review of these. Hypermotive has em. You can get them with very stiff springs.

Otherwise, you're just going to have to sell the Konis and grab some coilovers. They'll go nicely with the watts link, eh?

Also, remember to change evey bushing in the back to poly, including the one over the pumpkin.

I've got the H&R race. It's very nice.
 
1,022
99
Exp. Type
HPDE
Exp. Level
10-20 Years
Texas
further said:
Hey dude. Enjoyed suffering through the rainy weekend and the less than perfect instructors with you last weekend.

You want the stiffest springs you can get, short of going coilovers.

Here are the stiffest springs in order.

MM
H&R race
Eibach sportline

There is an additional option that I find interesting, the Ground Control coilover conversion kit designed for Koni Yellows. I have yet to hear a decent review of these. Hypermotive has em. You can get them with very stiff springs.

Otherwise, you're just going to have to sell the Konis and grab some coilovers. They'll go nicely with the watts link, eh?

Also, remember to change evey bushing in the back to poly, including the one over the pumpkin.

I've got the H&R race. It's very nice.

Does anyone know the spring rates of these three springs? I have the sport lines and I was looking for something stiffer for the track.
 
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roadhouse said:
MM springs are progressive. H&R is linear. If that plays into your decision at all...

The H&R are progressive. They have a basically linear rate in their working range. Strano recommends the H&R springs if you are not concerned about ride quality. He also thinks the MM springs are relabeled H&R. The MM springs come with bump stops for the application.
 
1,281
3
Tulsa, OK
2012-Boss said:
The H&R are progressive. They have a basically linear rate in their working range. Strano recommends the H&R springs if you are not concerned about ride quality. He also thinks the MM springs are relabeled H&R. The MM springs come with bump stops for the application.

Good to know. I was under the assumption they were linear but can't find anything to back it up.
 
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The key is that the H&R springs have a linear rate in their working range. That means when the spring is installed and the suspension is loaded with the car's weight, the spring rate does not change much in the normal range of motion.

If you placed the spring in a fixture and measured the rate(s), you would see changes when you first compress the spring and when approaching coil bind.

The working rate for the H&R race springs are 325 lb/in front and 285 lb/in rear.

I do not know if the MM springs' progressive rate works like the H&Rs or not. I do not think either are a bad option.
 
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I spoke with MM about their springs. They do have a slightly different rate than the H&R race springs. Basically, they have a higher rate when compressed but not enough to justify switching from one spring to the other. I would buy the MM springs for the slightly higher rate and they come with application specific bump stops.
 
From the Maximum Motorsports website: (The springs look very similar to the H&Rs)

Front: 1.8"
Rear: 1.9"
Lowering amounts are approximate, and will vary with year and model due to differences in car weight.

Spring Rates

Front: 320-360 lb/in. The rate is progressive and approximate, ramping up from 320 lb/in at ride height to 360 lb/in at 2" of spring compression (about 1.9" of wheel travel).
Rear: 260-380 lb/in. The rate is progressive and approximate, ramping up from 260 lb/in at ride height to approximately 380 lb/in at 2" spring compression (wheel travel is also 2" because the rear spring is on the axle).
Benefits

The H&Rs are a tad cheaper and probably a bit lower :eek:. You can just purchase some short bumpstops or simply cut the stock ones down.

Riding on them with the Koni's at full soft is actually comfortable on the street.
 
Thanks for all the input guys, I ordered a set of the H&R Race springs today' from Tirerack, I'll let you know how they test out on our terrible city streets here in Winston Salem, and on the track with Trackdaze (Grand Course VIR 8) ) the first week of November. The grand course is fun to run, I like trying to beat all the magazine "lightening lap" times

Here is a vid from running the Grand course in my old Atom vs a LL LP 670SV!

https://www.youtube.com/watch?v=059zxB_GDLc
 

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