mark b

I currently have Bilstein sports on my car, I have a set of PFADT shocks..Before I change them is there really a significant difference from the two in terms of shock action? Will the PFADT's eliminate the slight lift I feel coming up over a rise at speed or lessen the forward lean under heavy braking? I have Z06 sways and base springs..(Im changing the springs to Z06 soon.)
Ive also had these sports on my car for 3 years with an average of 8 to 10 track days a year...and they are still pretty firm..

so from anyone that has made the switch, is it worth the effort to change out to these shocks right now? will it lower my lap times? decrease the suspension settling time? decrease lift?

thanks

96CollectorSport

Not to be a smart a$$ but the Pfadts are adjustable and the Bilsteins aren't.

I've run the Pfadt sport shocks and what I like is the adjustability, I've turned up the front shocks at Road America so that the car behaved better under braking. If it rains out you can dial them back, it's that way with any adjustable shock. But you may find yourself playing with the **** trying to find that sweet spot. So people say if a shock has 16 settings 15 are wrong, with the Bilstiens your are set so all you have to do is drive.
If/when you run the Pfadts run 12f/9r or 11f/8r that's where I've set 2 or 3 different cars and they seem happy. If the car is pushing lower the front shock setting if it's loose then lower the back.
I really like the shocks and perfer them over non-adjustables, but maybe I just like turning *****

mark b

duh.. I know they are adjustable, I just wanted to know the feel/ difference between them.. I obviously wont be setting them too firm because my suspension wont be able to do it's job. I want to find that happy place for me and the car.
and as far as adjusting the shocks, are you able to reach under the car(not lowered) and get to the ***** without a jack? that would be ideal..I used to have adjustables in the past but only on the rear and it was easy to get them there, but the front I dont know..

thanks

grantar2

I am not sure the question is how firm. I dont' use Pfadt, I use Koni adjustable, however the issue isn't how firm, it's rebound. I gain significant control by changing stability but controling rebound. My guess is the Pfadts are similar. Stiffness can be a loser for control.

mark b

Ive heard the PFDATS control compression and rebound with one click(adjustment) true.. I dont want it too stiff either

gkmccready

KONI singles just adjust rebound, right? And the Pfadt's adjust bump & rebound?

Just want to point out that getting Bilstein to custom valve your shocks isn't crazy expensive... and DRM has lots of custom valvings sorted out already..

ghoffman

Try to get a dyno plot of each, otherwise it is just conjecture.

96CollectorSport

You have to turn the front wheels to lock to have room to get to the adjustment ****, rears are no problem. So yeah you can adjust without jacking up the car.

mark b

thanks

rfn026

This is a useless discussion without dyno sheets.

I had lunch one day at Sebring with the shock engineers from one of big firms. They said yu don't want to know how often they just pretend to change the shock settings. They look at the dyno sheets and segment times. If the driver is really obsessive about making changes they just fake it. They said the funny part is most of these drivers get faster and come back in raving about how great the (fake) changes were.

Adjusting a shock doesn't mean you're making it better. There's a 50% chance of making the car worse. Adjustments go in two directions.

Richard Newton

ghoffman

I tell my Penske customers that you need to try the bump adjusters on the cans (rebound, later) 5 clicks more and less at a test session just to adjust your "butt-o-meter", along with some sector times. We provide the dyno data at nominal, plus and minus on the bump and rebound for our shocks. If the vendors that you have in mind do not provide this, you are not getting a product with any real value. Why would a company buy a shock dyno, but not provide the customer paying the bills, your critical data?

mountainbiker2

Pfadt did give me a dyno chart of my shocks. Just ask them.

mgarfias

ANother difference no one has pointed out:

One set is made in germany, the other is made in Taiwan (and filled with fish oil based on smell).

Edited to add: ok, it might not be taiwan, might be korea. But whatever.

mark b

Ok, so technically which is the better shock? Bilstein? taking adjustment aside.. from experience with both shocks somebody please chime in, I know the Bilsteins are real good. Once you finally get a good setting on the Pfdats how does the car ride, feel, etc.. thanks

froggy47

I put Bil's on my trucks.

I have had Koni & QA1 & Pfadts (currently) on Corvettes.

I like the Pfadt's.

ghoffman

Is the provided data one run, or did they show you the effect of the adjusters? You originally asked about: "the slight lift I feel coming up over a rise at speed or lessen the forward lean under heavy braking". These are 2 very different things. The "slight lift" is a rebound function on all 4 corners, and the "forward lean" is the bump damping on the front and rebound in the rear. The more I do this, the more I feel that auto-x setups are as different from road course setups as drag race setups are. That is why I maintain that you not only need one dyno run, you need several to understand what the adjusters, or for that matter, a "revalve" job is doing.

rfn026

I've had the same feeling for a while now. When I ask what the top autocross guys are running they give me numbers that would be really bad for the track. The more I talk to people the only reasonable answer is that the transitions happen much faster in autocross.

We don't really get too aggressive on the track - at least compared to what winning autocross guy do. Several years (decades?) ago Derek Bell was trying to teach me how to drive. After 3 laps he asked "Do you drive a lot of autocross events." At that time I was national champion in my class so I replied "I've driven a few of them"

He said I drove like an autocross guy - way too aggressive for the track.

Maybe that's why the setups have to be different?

Richard Newton
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timd38

I am sold on Pfadt products. They just work better. I took the Bilsteins off and replaced them Pfadt coilovers and am really happy with them.

It took me a while to say yes to the Pfadt kit, but I would have saved a bunch of money buy just getting the Pfadt kit and not messing around with trying to make my own by mixing and matching parts. Plus Pfadt stuff just looks good.

mountainbiker2

Autocross is all about transitions. The time spent at mid-corner (where shocks do very little) is very small compared to Road Racing.

rfn026

The most difficult part of making adjustments is just identifying the 3 parts of the corner and knowing what the car is doing. I have an adjustable rear sway bar. The key is knowing what the car does on entry. The middle of the corner really isn't that important and if you can't make a Corvette oversteer on exit you doing something really wrong.

The bottom line is none of us get enough seat time. Maybe we all need to be concerned with looking good. That's the way is is at a Ferrari track day. Everyone just looks so cool.

Richard Newton