Shocks/Struts going bad?

[Branomano08BlackBullitt]

Hey guys, I installed the Eibach Pro-Kit springs on my car when it had around 500 miles on it, it currently has a little over 27,000 miles on it and it is starting to get.. more... hmm lets see how to explain this... I guess the words would be "flat" feeling? It has clunks coming from what seems to be all 4 corners... I definitely feel bumps more then I previously was... it just seems like there is very little... rebound? Anymore... if it helps.. I am on the stock 18" Bullitt's wrapped in 275/40/18 Hankook Evo V12's all around.

Also a question that is not related to this or possibly is... Once I got these tires which I personally love, although its not like I have much experience, I find them to be MUCH better then stock. Anyway I have found that in longer sweeping turns at speed I have the grip but the back end feels very.. "floaty"? It feels pretty planted but its not a very comfortable feeling at the same time.. is this driver error while entering the turn? Or something to do with suspension?

Thanks for any help you guys can give, I appreciate it.

 

[SoundGuyDave]

Generally, if a shock still has it's gas charge, and isn't leaking fluid, it's classified as "good." If you're getting clunks, and it's coming from the dampers, then they most likely have leaked out the gas, so a quick check would be to remove them, compress them by hand, and see if the rods pop back up or not. While you're in there, just give all the damper, swaybar, swaybar link, and control arm bolts a quick torque check to make sure nothing came loose. Next on the list would be the upper strut mounts, since those seem to go bad at the drop of a hat. That wouldn't explain the rear, though.

As for your "planted, yet floaty feel," what are you doing with the throttle during the aforementioned sweeper? Are you off-throttle, neutral (maintaining speed), or accelerating? Also, any other suspension mods besides springs and dampers?

 

[Branomano08BlackBullitt]

As for your "planted, yet floaty feel," what are you doing with the throttle during the aforementioned sweeper? Are you off-throttle, neutral (maintaining speed), or accelerating? Also, any other suspension mods besides springs and dampers?

I am usually neutral (maintaining speed) when that happens.

Also, I am running the stock dampers only aftermarket suspension part are the springs.

 

[SoundGuyDave]

Ah, okay. I thought the pro-kit was, well, a kit... Hopefully Sam Strano will chime in here, but I would bet that it could be a combination of damper mismatch to the springs and weight transferrance. I would bet that if you were to actually try to accelerate slightly through the corner, you'd have a more planted feeling. Whether or not it's planted "enough," though, may come down to hardware. Should I assume that all the stock bits (control arm bushings, panhard bar bushings in particular) are all in good repair?

 

[Branomano08BlackBullitt]

Ah, okay. I thought the pro-kit was, well, a kit... Hopefully Sam Strano will chime in here, but I would bet that it could be a combination of damper mismatch to the springs and weight transferrance. I would bet that if you were to actually try to accelerate slightly through the corner, you'd have a more planted feeling. Whether or not it's planted "enough," though, may come down to hardware. Should I assume that all the stock bits (control arm bushings, panhard bar bushings in particular) are all in good repair?

It's funny you say that, because the floaty feeling usually does go away when I accelerate in the corner. All the stock bits should be in good condition as far as I can tell.. and I take in in for maintenance every 6000 Miles, and have them check everything so assuming they do a decent job (which is dumb on my part but it's the best I can do with my current knowledge of suspension) then it should be in good condition.

 

[SoundGuyDave]

Cool! Then you could call that "driver error," in a way. Just remember that feeling, and how you fixed it for future reference! Driving the twisties is ALL about weight transfer and managing that transfer. I tend to think of the pedals and wheels as ways to move the weight around, and let that help the car go the way I want, rather than as just controls. When you accelerate, you transfer weight to the rear of the car. When you brake, it transfers to the front. When you turn, it transfers to the outside of the corner. When you're in a corner, you have the weight leaning on the outside tires, and under neutral throttle, you're getting just a little more slip from the rear than you are from the front, and that's what's giving you your "floaty" feeling. Just a touch more gas will shift a little bit of the weight towards the rear, which will give the rear that little bit of extra grip you're looking for. As a general rule, understeer (front end pushing) is a stable condition, and oversteer (rear end trying to kick out) is unstable. By moving the weight towards the rear with a little bit more gas, you have shifted the handling characteristics of the car from oversteer (floaty) to understeer (planted). Pretty cool, huh? That whole deal is also why if you were to suddenly lift off the throttle, or, God forbid, hit the brakes in the middle of that sweeper, you would move from slight understeer to massive oversteer when the rear end unloads, and you wind up spinning the car...

Next cool trick, and great demo of the above: Find a freeway with a nice, smooth on-ramp, and holding a nice, constant, REASONABLE speed, line the car up on the center of the ramp. Now, gently ease off the throttle (transfers weight forward) and watch your car drift in towards the inside of the ramp. Then, gently roll into more throttle, and watch the car drift towards the outside of the ramp. Remember, you haven't changed the steering angle at all! That's a technique called "throttle steering," and is a pretty neat technique to have if/when you wind up hitting the local race track...

 

[Branomano08BlackBullitt]

As a general rule, understeer (front end pushing) is a stable condition, and oversteer (rear end trying to kick out) is unstable. By moving the weight towards the rear with a little bit more gas, you have shifted the handling characteristics of the car from oversteer (floaty) to understeer (planted). Pretty cool, huh? That whole deal is also why if you were to suddenly lift off the throttle, or, God forbid, hit the brakes in the middle of that sweeper, you would move from slight understeer to massive oversteer when the rear end unloads, and you wind up spinning the car...

Next cool trick, and great demo of the above: Find a freeway with a nice, smooth on-ramp, and holding a nice, constant, REASONABLE speed, line the car up on the center of the ramp. Now, gently ease off the throttle (transfers weight forward) and watch your car drift in towards the inside of the ramp. Then, gently roll into more throttle, and watch the car drift towards the outside of the ramp. Remember, you haven't changed the steering angle at all! That's a technique called "throttle steering," and is a pretty neat technique to have if/when you wind up hitting the local race track...

I love reading this stuff... all these techniques are so helpful and they are things I have sort of learned on my own just driving my car, I just didn't know what they were called. I have learned a lot of terms and just learned 2 more lol. I am only 18 but ever since I got behind the wheel of my first Mustang I have had such a passion for driving, and not just fast... but I enjoy looking for the best "line" on a street so I can drive it really smooth even when I am not driving.. lets call it spirited.. lol. I had to learn never to push beyond your limits the hard way..... and lost a great car because of it... I really really need to get out to a track event... I really don't like the idea of racing through cones.. but I will take what I can get over in the Los Angeles area... need to look around more... just been busy with school...

Thanks for the help SoundGuyDave, I have learned a lot from your posts and truly appreciate it. I think I am gonna see about some Koni Yellows and maybe that will help with the change in ride I have felt.

 

[SoundGuyDave]

I had to learn never to push beyond your limits the hard way..... and lost a great car because of it... I really really need to get out to a track event... I really don't like the idea of racing through cones.. but I will take what I can get over in the Los Angeles area... need to look around more... just been busy with school...

Thanks for the help SoundGuyDave, I have learned a lot from your posts and truly appreciate it. I think I am gonna see about some Koni Yellows and maybe that will help with the change in ride I have felt.

You're quite welcome! First off, if you have questions about dampers, get in touch with Sam Strano (stranoparts.com), he is the guru! And, if you want to learn about really driving, jump over to NasaProRacing.com, and sign up for HPDE-1 at one of their events near you. They'll put you on a race track (not a parking lot!) with an instructor in the car with you and give you some serious coaching, one-on-one, and the best part is that it's not really THAT expensive! Have fun, be safe, and keep the racy stuff where it belongs, on a track.

 

[Branomano08BlackBullitt]

Sick, I just checked the site out, looks like there is something I can go to on the 22nd, over at Willow Springs =). Looks to be about an hour or less away from me, not bad at all. Thanks for showing me that site.. I am getting excited lol.

 

[Sleeper_08]

Dave

Now you've done it - another one will get addicted

 

[Sam Strano]

Stock shocks are valved for stock springs, and not all that well for those either. What's more is they aren't built to last. OE's don't much care what happens to them once they aren't responsible for them.

By 5k miles it's not uncommon for folks still on stock springs to complain the car is feeling bad. Harder riding, less stable, "squishy" and "floaty"... Add lowering springs, and it gets even worse because you're forcing those stock dampers to *try* and control more spring rate, in a lesser amount of travel. What you need there is better rebound control, not less.

It's time to put some real dampers on there. I'd certainly recommend Koni Sports here given how well they work, and the fact they are on sale (and that I run them on own car). I also have a set of AST's too, and so does SoundGuyDave, but that's a much more serious commitment and more than a little more money too. Here, we'd want Koni Sports which are currently $629/set shipped....

 

[ArizonaGT]

Sam, how much are you selling the AST kits for? I don't see any info on your website.

 

[Sam Strano]

Looking at about $2400 shipped depending on spring choice, where you live, etc. for a complete setup with adjustable coil-over front/weight jack rears and springs.

 

[Branomano08BlackBullitt]

Hmm alrighty then, well its my B-day tomorrow so maybe we will talk Sam =) I am fairly certain I will be getting enough to grab those.. been wanting the Koni's for awhile now... have only heard awesome stuff about them.

 

[SoundGuyDave]

Dave

Now you've done it - another one will get addicted

Heh, heh, heh... the first dose is free...

Honestly, I think "Welcome to your new addiction" should be my sig line...