The spring rate balance on the stock Mustang suspensions is such that there is more rate at the rear than the front, as many here know.
For instance, the Brembo brake package has 167 lbs/in rear springs and 131 lbs/in front springs, for a 79% front:rear ratio. The front sway bar is 34.6mm in diameter (and tubular), while the rear bar is 24mm in diameter (and solid).
This seems to result in a rather neutral-handling car from the accounts I've read (I've not tracked mine yet so I don't know from firsthand experience what the real balance is, but when Randy Pobst says that the car doesn't understeer, I'm inclined to believe him).
The Boss 302 has an 80% front:rear ratio, so there's a bit more rate in front relative to the rear than the GT, and it has a staggered tire setup, but it also has a 25mm sway bar in the rear, so I can see how that combination could again result in a neutral handling car.
The Laguna Seca has a 72% front:rear ratio, a 26mm sway bar, and a staggered tire setup. I would thus expect it to oversteer more than the standard Boss 302.
But every lowering kit I've seen, along with every coilover setup I've seen or read about, has greater rates in the front than in the rear. Coilover setups, in particular, often seem to have massively greater rates in the front than in the rear (e.g., 550 lb/in in the front and 350 lb/in in the rear, for a 157% front:rear ratio).
My question, thus, is this: how in the world can the neutral handling characteristics of the car possibly be retained with, e.g., the coilover setups that are often run, most especially when (as Rehagen Racing apparently does) the rear bar is deleted entirely? Wouldn't the result instead be a car which understeers massively?
Moreover, it seems to me that even if you compensate by using more rear bar relative to the front, you'd wind up with more instability in the rear when going over asymmetric bumps.
So: is anyone running a coilover setup with less spring rate in the front than in the rear? And why is the prevalent setup the one that you would expect to result in significant understeer?
Or am I missing something monumentally important and fundamental in all this?
For instance, the Brembo brake package has 167 lbs/in rear springs and 131 lbs/in front springs, for a 79% front:rear ratio. The front sway bar is 34.6mm in diameter (and tubular), while the rear bar is 24mm in diameter (and solid).
This seems to result in a rather neutral-handling car from the accounts I've read (I've not tracked mine yet so I don't know from firsthand experience what the real balance is, but when Randy Pobst says that the car doesn't understeer, I'm inclined to believe him).
The Boss 302 has an 80% front:rear ratio, so there's a bit more rate in front relative to the rear than the GT, and it has a staggered tire setup, but it also has a 25mm sway bar in the rear, so I can see how that combination could again result in a neutral handling car.
The Laguna Seca has a 72% front:rear ratio, a 26mm sway bar, and a staggered tire setup. I would thus expect it to oversteer more than the standard Boss 302.
But every lowering kit I've seen, along with every coilover setup I've seen or read about, has greater rates in the front than in the rear. Coilover setups, in particular, often seem to have massively greater rates in the front than in the rear (e.g., 550 lb/in in the front and 350 lb/in in the rear, for a 157% front:rear ratio).
My question, thus, is this: how in the world can the neutral handling characteristics of the car possibly be retained with, e.g., the coilover setups that are often run, most especially when (as Rehagen Racing apparently does) the rear bar is deleted entirely? Wouldn't the result instead be a car which understeers massively?
Moreover, it seems to me that even if you compensate by using more rear bar relative to the front, you'd wind up with more instability in the rear when going over asymmetric bumps.
So: is anyone running a coilover setup with less spring rate in the front than in the rear? And why is the prevalent setup the one that you would expect to result in significant understeer?
Or am I missing something monumentally important and fundamental in all this?
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