CSG Spec Tein Flex A Owners Thread

[itschris]

Originally Posted by Var

Ok..so this is a huge problem for me right now. I adjusted my rear preload to where it's supposed to be, and as you saw in the photo, the rear end of my car was sagging by quite a bit. With all the extra preload removed and a saggy butt, I went for a drive around the block, maybe 2 minutes, just to see if the ride quality had improved. I found that it had not. It's much harsher on the high velocity compression than before the car was lowered. It seems really crashy now. I'm going to remove the wheels and dampers and jack the suspension up and down through the full range of motion to make sure there's no binding, but i'm almost certain there isn't. It's just a ride quality difference.

Why would the ride height affect harshness with these type of shocks where ride height/damper length and preload are independent of each other and stroke length?

Provided there's no binding, you could be bottoming similar to timurrrr. Adding preload increases available bump travel at the expense of droop. Your extra bump travel from cranking up the preload might have prevented bottoming. The car's weight will compress a spring a fixed amount (f = kx). Raising the spring collar just changes the offset on which the car sits relative to the shock body (which is fixed relative to the wheel). timurrr's videos do a good job of explaining this.

Increasing preload can have issues. A too short spring might result in coil bind (spring now has less compression travel available than the shock). Too much preload can also overwhelm rebound damping, the damper is not designed to handle the additional force pushing the wheel down. This is why CSG and most manufacturers have a recommended setting.

The addition of a helper spring mostly negates the second issue. It allows coilovers such as entry level KWs, Bilsteins, etc. to add preload without overwhelming the damper. An issue with that design means corner balancing a car will change bump/drop travel ratios by different amounts at each corner. The FLA design allows for bump/droop ratio and ride height to be adjusted independently.

Back to your question - yes, ride height adjusted via the damper length and NOT preload can still effect ride harshness. In the rear, lowering the length and ride height moves us to a section of travel with less anti-squat and a lower roll center. Less anti-squat means we're using more travel on bumps and acceleration, and a lower roll center means we're using up more bump travel in turns. Same deal in the front regarding roll center. Using more travel means we'll be more bumpstop active.

[CSG Mike]

Engineering at Wisefab confirms that using ONLY the drop of the Wisefab rear kit and raising the originally-lower-than-stock height of your CSG FLA via longer sleeve would put the roll center correction as intended.

[Var]

Originally Posted by itschris

Back to your question - yes, ride height adjusted via the damper length and NOT preload can still effect ride harshness. In the rear, lowering the length and ride height moves us to a section of travel with less anti-squat and a lower roll center. Less anti-squat means we're using more travel on bumps and acceleration, and a lower roll center means we're using up more bump travel in turns. Same deal in the front regarding roll center. Using more travel means we'll be more bumpstop active.

So does that mean I need dampers designed to work in a completely different range? Remember I lowered the height with drop spindles and INCREASED the length of the damper to maximum allowable height. Does it still have the same effect? I guess I don't understand why the damper length matters. It's just a sleeve at the bottom that doesn't affect stroke at all right? So is it strictly the new geometry that's the culprit?

Also, my antisquat should be back to normal even at this ride height with the wisefab kit, or darn close. Should definitely not be worse than a car lowered by just coilovers, which I was previously, and it was very comfortable.

Originally Posted by Wisefab

"If the focus is more towards performance, then the car will drive even better with lowered ride height, but then the factory designed kinematics won’t work as they are supposed to. Wisefab suspension kit brings the roll center, bumpsteer, anti-squat and camber curve back to normal range, provides better roll stiffness, handling and grip."

[Var]

Originally Posted by CSG Mike

Engineering at Wisefab confirms that using ONLY the drop of the Wisefab rear kit and raising the originally-lower-than-stock height of your CSG FLA via longer sleeve would put the roll center correction as intended.

Raising it by how much before it's out of spec?

[timurrrr]

Originally Posted by Var

Why would the ride height affect harshness with these type of shocks where ride height/damper length and preload are independent of each other and stroke length?

You're hitting bump stops?

Suggestion:
1) Measure your A and B. I put a long Allen wrench on top of the damper body to help precisely measure A with a caliper.
2) Compare your (A-B) with the (A-B) recommended in the instruction manual. If your (A-B) is greater than recommended, add preload (by increasing B).
3) Optionally, add up to ~10 mm of extra preload, if you're comfortable sacrificing the droop travel.
4) Extend the damper body length (by increasing A) as much as you're comfortable.

How much lower than desired ride height is your final setup? Ignore angles of the arms.

If it's still too low, you need extended sleeves.

[Var]

Originally Posted by timurrrr

You're hitting bump stops?

Suggestion:
1) Measure your A and B. I put a long Allen wrench on top of the damper body to help precisely measure A with a caliper.
2) Compare your (A-B) with the (A-B) recommended in the instruction manual. If your (A-B) is greater than recommended, add preload (by increasing B).
3) Optionally, add up to ~10 mm of extra preload, if you're comfortable sacrificing the droop travel.
4) Extend the damper body length (by increasing A) as much as you're comfortable.

How much lower than desired ride height is your final setup? Ignore angles of the arms.

If it's still too low, you need extended sleeves.

My ride height is so out of whack that it honestly doesn't matter what I want right now as far as ride height. I want my rear ride height roughly an inch higher. So if I understand you correctly, my preload is just not set correctly. It was too much before, and it's possible not enough now.

Also, still don't understand how I can be hitting bump stops. The ride is harsher in general. Not just over large articulation. Do you mean that I'm engaging HBS all the time? My damper length is all the way out/long. How would that happen?

[itschris]

Originally Posted by Var

So does that mean I need dampers designed to work in a completely different range?

Only if you're changing height via preload. If instead you get extended bottom shock mounts, it sounds like the FLAs will work closer to how they were designed. The adjustability on the dampers affords a minor change in preload, probably no more than a few turns.

Originally Posted by Var

Remember I lowered the height with drop spindles and INCREASED the length of the damper to maximum allowable height. Does it still have the same effect? I guess I don't understand why the damper length matters. It's just a sleeve at the bottom that doesn't affect stroke at all right? So is it strictly the new geometry that's the culprit?

Yes, I think the new geometry is the culprit. From Mike's posts, it sounds like even raising the FLAs to maximum allowable height is lower than OEM. You're correct that stroke isn't affected, but with less anti-squat more of that stroke will be used up on the same bump or during acceleration.

Remember, not all reactionary forces to a bump are from the spring/strut assembly. Anti-squat describes the loading of the suspension linkages. With a raised car, more forces are going to be stored in the linkages/bushings, and less in the spring/strut assembly. This can be good, for example under cornering. The compression on the outside rear tire will bring the suspension into a range of travel that doesn't have as much anti-squat. The spring/strut assembly is now left to handle mid corner bumps. Have you noticed that our cars tend to eat bumps better while cornering, as opposed to when going down the highway?

Too little anti squat, and you'll not have enough travel left for bumps. Jacking forces are designed in because there are benefits, especially in travel limited applications. Too much is obviously bad and too little can have negative effects as well. It's just another tool you have available.

[timurrrr]

Originally Posted by Var

My ride height is so out of whack that it honestly doesn't matter what I want right now as far as ride height. I want my rear ride height roughly an inch higher. So if I understand you correctly, my preload is just not set correctly. It was too much before, and it's possible not enough now.

Yeah there's a pretty narrow range of the amount of preload you can use without either hitting bump stops all the time, or lifting wheels off the ground. The amount recommended in the manual is a good starting point, and then you can make micro-adjustments if you want to achieve something different.

What is the ride height you get if you follow my recent recommendation? Is it any good, or still way too low?

[Var]

Originally Posted by timurrrr

Yeah there's a pretty narrow range of the amount of preload you can use without either hitting bump stops all the time, or lifting wheels off the ground. The amount recommended in the manual is a good starting point, and then you can make micro-adjustments if you want to achieve something different.

What is the ride height you get if you follow my recent recommendation? Is it any good, or still way too low?

Around an inch too low still. Minimal change.

[timurrrr]

Originally Posted by Var

Around an inch too low still. Minimal change.

Then you need an extended sleeve that's at least 20mm longer.

[Var]

Originally Posted by timurrrr

Then you need an extended sleeve that's at least 20mm longer.

Still waiting for some details from Mike on this. Wisefab engineering says I can raise the car. I just want to confirm by how much before everyone wastes time and money on this solution. The fact that I need longer sleeves for the rear was pretty apparent already. I just don't want to compromise the geometry.

Even if I go with the extended sleeve solution, I'm going to need some guidance on raising the car and measuring the rear arm angles so I don't go too high. If this is all possible and I can get really close, like..say within 5mm of where the rear end of the car was before the Wisefab kit, and still be in the optimal geometry zone, I will accept this as the solution to my problem. Unless they just tell me flat out I can raise it an inch and not worry. Then we're golden. Although I'm still obviously going to measure it when we're done.

[CSG Mike]

Originally Posted by Var

Still waiting for some details from Mike on this. Wisefab engineering says I can raise the car. I just want to confirm by how much before everyone wastes time and money on this solution. The fact that I need longer sleeves for the rear was pretty apparent already. I just don't want to compromise the geometry.

Even if I go with the extended sleeve solution, I'm going to need some guidance on raising the car and measuring the rear arm angles so I don't go too high. If this is all possible and I can get really close, like..say within 5mm of where the rear end of the car was before the Wisefab kit, and still be in the optimal geometry zone, I will accept this as the solution to my problem. Unless they just tell me flat out I can raise it an inch and not worry. Then we're golden. Although I'm still obviously going to measure it when we're done.

.

Originally Posted by Var

Mike, you are dense as hell, or really good at being disingenuous and running interference for David. Have a nice day

.

Originally Posted by Var

Good day Mike. Thanks for the show

.

Originally Posted by Var

Don't worry about me. I'm not here for a pity party. The money issue will get resolved in private. I'm just trying to sort out the actual physics of the problem for others to not make the same mistake. And Mike is just defending his ego or David's company rather than being genuine and addressing the issue, and literally would rather give out bad advice to the public rather than admit that a sleeve solution would ruin the geometry in my particular situation. And I'm definitely not going to use that as my solution. Others can feel free to try

I'll be happy to help when you acknowledge what has happened.

[Var]

Originally Posted by CSG Mike

.

.

.



I'll be happy to help when you acknowledge what has happened.

You wouldn't acknowledge that there was a problem with my combination of parts and you were talking past me. If you really want me to dig up all your deflections and inconsistent responses, I can do that.

Also, I already told CSG in an email that I would accept their rear sleeve solution if they guaranteed me no rear geometry defects. That was before I even posted in here. I didn't get any response after I asked them for that assurance.

[Var]

Also, still waiting for word about how much higher I can raise the car from the FLA's maximum height. Otherwise the only way to find out would be to spend more money, which doesn't seem very efficient on either of our ends.