Coilover Recommendations

[marolf101x]

PDC:
"Took her to a local shop and they pulled the shocks and found out that they were completely empty. FWIW - these shocks are nitrogen filled, which the guys at the shop indicated aren’t really for street driving."
I would completely disagree with this statement. Each year the OE's kick out millions of cars with nitrogen charged shocks. The main difference is that they are not easily adjustable (no Schrader valve or rubber pellet system).

Extremely low nitrogen pressure will result in a "non-repeatable" shock. The nitrogen (in a monotube shock with the gas and oil separated by a dividing piston) is used to provide pressure against the oil column. This pressure is intended to keep the oil column "solid" so no air bubbles form when the shock piston is traveling through the oil column. A shock tuner can change the nitrogen pressure to fine tune the shock. Typically you want the least amount of pressure that keeps the oil column solid.
As the shock compresses the volume of the shock shaft must be offset (if it's not, the shock blows up due to hydraulic lock). So as the shaft is pushed into the shock, the oil column increases by the amount of the shock shaft volume, pushing the dividing piston down, and further compressing the nitrogen.
Higher nitrogen pressures make it more difficult to push the shaft in.


"Right now, I am just looking to see what the typical range is for spring rate / length / and shock travel."
You can look this up on this site as I've covered it a number of times, but it's always worth repeating.
You typically want a minimum of 5 inches of WHEEL travel to properly soak up the normal bumps you see during normal street driving. 3 inches should be available for compression, 2 inches for extension (you are hitting bumps and pushing the wheel up into the wheel well more often than you are jumping the car and letting the wheel hang from the vehicle.
Motion ratio is the correlation between how far the shock/spring moves compared to the wheel. Every car on this forum has some motion ratio. . .typically around 2:1. So if the wheel moves a total of 5 inches, the shock moves only 2.5 inches.
I don't care if the shock has 10" of shaft showing, it only moves 2.5 inches in the case above.
The closer the lower shock mount is to the lower ball joint, the better the motion ratio, and the more effective the shock/spring can be.


"For my purposes, I definitely would be glad to give up some handling capabilities for ride comfort"
Well, this might be easier said than done, depending on what you feel is acceptable ride quality.
Pro touring cars are designed and built to handle. Handling requires removing all flex from the suspension joints, and shocks/springs that react as quickly as possible.
After thinking about this and re-reading many threads where we've discussed this before, the latter may be where most people are having difficulty.



In a pro-touring car the higher end shocks are providing very strong forces at very low shaft speeds. For example, if you compress the shock and the shock shaft is moving at 0.5 inches/second, it might be pushing back with 700lbs force. . .(depending on the shock and how it's built, it could be providing nearly no force, or a metric crap ton of force, it all depends.)

So, my theory was always to use a linear valve stack on compression, with as little force as we could get at low shaft speeds. As the shaft speed increases, so does the force. Small undulations, not much force coming from the shock. . .hit an expansion joint, the shaft probably moved at 12-20 inches per second and provided 400-600lbs of force (but you need that force to help the spring slow down the wheel/tire before it smacks the compression stops.)
I liked a lot of rebound force at slow shaft speeds. . .let the shock compress, soak up the bump, then do most of the control on the extension side. Increases performance at a minimal cost to ride quality.


The way to increase ride quality is to soak up the bumps before the force is transmitted into the driver cabin.
The ways to increase ride quality:
-"softer" shocks
-light spring rates (or progressive springs)
-more suspension travel
-larger profile tires
-large rubber bushings at all joints
-anything that makes the cabin quieter
-better seats

[Rod]

kinda a fun engineery thread....
but it is still an everyone's is best thread, I have JRI so its best, I have ridetech so its best, I have QA1 so its best....

[FORDvsCHEVY]

kinda a fun engineery thread....
but it is still an everyone's is best thread, I have JRI so its best, I have ridetech so its best, I have QA1 so its best....

I have air ride it’s definitely the best!