Tire rubbing with rolled fenders!

bubblehead93

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The bounce test works, it should not bounce, simple, you push it down, it should rise back up to normal ride height, if it bounces then either the shock is worn or if you have a mismatched spring/shock combo then it is under-damped. With the race springs, it is hard to do this check because the springs are so stiff. Need to replace the struts/shocks on my wife's Flex, this test is very obvious because the suspension is so soft and compliant, it bounces. Since you run a spring/shock vice coilover setup, I would just remove the shocks on both sides, a good shock will take some real effort to compress and extend. Check them both in an absolute sense as well as compare to each other. Again, even the stock Cobra Bilsteins take some force to compress and extend.

As far as the Cobra R spec Bilsteins, they are roughly equivalent to a MM's MM2 series race damper which with the H&R race springs will likely give you a slightly over-damped condition. Ran H&R race springs with MM2 series dampers for a while, running hard if you really worked the suspension the over damped condition really affected the handling, actually performs much better with the higher spring rate (at the wheel) that I run now with coil-overs. The important piece is matching spings with dampers, I think you will find the R spec Bilsteins with the race springs will not be a good performing match-up.

this is not a spring/shock versus coilover issue. This is a shock problem given the wheel/tire combo should work. I think you have a bad shock, when you hit it, very little damping occurs on compression and you are bottoming out on the tire.

JMHO...

For the record though, you were asking about QA-1 shocks... here is my story... the ones you link to though are smooth body, the only QA-1 coilover shocks for IRS that I am aware of are a fully threaded body... which you will see in the pictures... again, I don't think you need to go coilover to solve your problem... though my MM2 series dampers with higher spring wheel rates with coilovers than my H&R race springs I used to run, ride much better than the race springs...

http://www.svtperformance.com/forums/showthread.php?1071722-IRS-Coil-Over-Auto-X-and-Drag-setups

r/
Andy
 

Bdubbs

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The bounce test works, it should not bounce, simple, you push it down, it should rise back up to normal ride height, if it bounces then either the shock is worn or if you have a mismatched spring/shock combo then it is under-damped. With the race springs, it is hard to do this check because the springs are so stiff. Need to replace the struts/shocks on my wife's Flex, this test is very obvious because the suspension is so soft and compliant, it bounces. Since you run a spring/shock vice coilover setup, I would just remove the shocks on both sides, a good shock will take some real effort to compress and extend. Check them both in an absolute sense as well as compare to each other. Again, even the stock Cobra Bilsteins take some force to compress and extend.

As far as the Cobra R spec Bilsteins, they are roughly equivalent to a MM's MM2 series race damper which with the H&R race springs will likely give you a slightly over-damped condition. Ran H&R race springs with MM2 series dampers for a while, running hard if you really worked the suspension the over damped condition really affected the handling, actually performs much better with the higher spring rate (at the wheel) that I run now with coil-overs. The important piece is matching spings with dampers, I think you will find the R spec Bilsteins with the race springs will not be a good performing match-up.

this is not a spring/shock versus coilover issue. This is a shock problem given the wheel/tire combo should work. I think you have a bad shock, when you hit it, very little damping occurs on compression and you are bottoming out on the tire.

JMHO...

For the record though, you were asking about QA-1 shocks... here is my story... the ones you link to though are smooth body, the only QA-1 coilover shocks for IRS that I am aware of are a fully threaded body... which you will see in the pictures... again, I don't think you need to go coilover to solve your problem... though my MM2 series dampers with higher spring wheel rates with coilovers than my H&R race springs I used to run, ride much better than the race springs...

http://www.svtperformance.com/forums/showthread.php?1071722-IRS-Coil-Over-Auto-X-and-Drag-setups

r/
Andy

Some great information, I appreciate it. So do you suggest I just buy new oem rear shocks?
 

bubblehead93

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I really like MM because they have great tech support even though you can get equivalent "re-valved" bilsteins much cheaper elsewhere...

this is a pretty good reference...

http://www.maximummotorsports.com/tech_struts_shocks_matching_spring_rates.aspx

there is a bunch of threads out there with regard to finding an equivalent to the OEM coupe shocks... however, the HDs are close and will be just fine and are widely available...

r/
Andy
 

Bdubbs

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I really like MM because they have great tech support even though you can get equivalent "re-valved" bilsteins much cheaper elsewhere...

this is a pretty good reference...

http://www.maximummotorsports.com/tech_struts_shocks_matching_spring_rates.aspx

there is a bunch of threads out there with regard to finding an equivalent to the OEM coupe shocks... however, the HDs are close and will be just fine and are widely available...

r/
Andy

Okay. I can get stock one's from Autonation Ford. And likely have them by Tuesday as they are only 1 1/2 hours from me.
 

Bdubbs

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Well the h&r race rear spring rates are 770 and the cobra r rears are 750. Is that so far off that some don't recommend putting the cobra r b8 shocks on our cars?
 

bubblehead93

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good question, based on the MM FAQ page it looked like the Cobra R shocks are valved very similar to MM's MM2 series race damper which I have a lot of experience with for H&R race springs. I did not compare H&R race with the Eibach springs on the Cobra R. I would give the folks at MM a call or email them. I have had good experience with them, to the point of them recommending struts/shocks that they don't carry but recommend for a specific application. I think you will find they will answer your question honestly without trying to sell you something you don't want or need.

r/
Andy

r/
Andy
 

Bdubbs

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good question, based on the MM FAQ page it looked like the Cobra R shocks are valved very similar to MM's MM2 series race damper which I have a lot of experience with for H&R race springs. I did not compare H&R race with the Eibach springs on the Cobra R. I would give the folks at MM a call or email them. I have had good experience with them, to the point of them recommending struts/shocks that they don't carry but recommend for a specific application. I think you will find they will answer your question honestly without trying to sell you something you don't want or need.

r/
Andy

r/
Andy

Yeah I emailed them a couple days ago about my issues and asked if there coilovers would solve the problem. They said likely not. He asked what my rear alignment camber is at. I just emailed them stating possibly a bad shock. I'll see what they say, then ask what they recommend for a shock.
 

94slowbra1

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One thing to remember is the cobra r shock is discontinued. The b8 is taking its place but is valved slightly different than the r I believe. They are still similar shocks
 

Woody6799

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Yeah I emailed them a couple days ago about my issues and asked if there coilovers would solve the problem. They said likely not. He asked what my rear alignment camber is at. I just emailed them stating possibly a bad shock. I'll see what they say, then ask what they recommend for a shock.

This is why I love dealing with MM. They very easily could have said probably and then sold you a kit. They did the same to me and told me straight what parts I didn't need even though they were going to make the money. Hopefully you get this all figured out bud.
 

Bdubbs

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Yup I agree MM seems to be a stand up company. I did go for a short cruise, basically normal driving. I had zero rubbing when driving normal.
 

Kyle_KleinSS

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What about the koni adjustable shocks? The have the big sales every spring it seems like. I almost picked them up this past year. How do they compare to the qa1?
 

FromGTtoSVT

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just throwing this out there......you can have the factory bilsteins re-valved, might be a good option

Sorry to hear about all the trouble, cars can be frustrating, especially after dropping the coin on TF wheels. Keep at it, you'll figure it out eventually.
 

Woody6799

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just throwing this out there......you can have the factory bilsteins re-valved, might be a good option

Sorry to hear about all the trouble, cars can be frustrating, especially after dropping the coin on TF wheels. Keep at it, you'll figure it out eventually.

you used to be able to. From my understanding they don't do it anymore for OEM
 

Bdubbs

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Still haven't heard back from mm on rear shocks. I may send out a new email. Maybe there HD rear shocks?
 

94slowbra1

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just thought id give an update on some info from MM about rear shocks. i emailed them before this thread started asking about rear shocks with H&R race springs. here is jacks response:
"I would use the H&R Race springs with the MM Street damper and the Bilstein Cobra R shock. This damper setup will be about 25%
stiffer than what is currently on the car. The springs are about 40% stiffer than stock."
take this info for what you will. i just received my b8/cobra r shocks today so i will be installing over the weekend. and ill be ordering the fronts some time next week. ill update in a new thread how they feel compared to oem
 

Bdubbs

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just thought id give an update on some info from MM about rear shocks. i emailed them before this thread started asking about rear shocks with H&R race springs. here is jacks response:
"I would use the H&R Race springs with the MM Street damper and the Bilstein Cobra R shock. This damper setup will be about 25%
stiffer than what is currently on the car. The springs are about 40% stiffer than stock."
take this info for what you will. i just received my b8/cobra r shocks today so i will be installing over the weekend. and ill be ordering the fronts some time next week. ill update in a new thread how they feel compared to oem

Good to hear, I may just order up those b8 shocks. I don't feel like changing out my front struts at the moment though. Just wondering if it's ok to just do rears?

I'd like to know how you like them.

Edit: Just ordered the bilstein b8 rear shocks.
 
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fr03cobra

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good info here. I just put 18's on and we are going to cut the oem spring to lower it alittle. I hope I don't have this problem. putting the qa1 rear shock on here soon.
 

Joe5.0

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Interested on how this turned out for you? I just put my CCW's on the cobra, 18x11 rears 335/30/18's I'm getting some rubbing on the inside on most bumps and turning as well. I believe my stock shocks are to soft for the H and R race springs.
 

Bdubbs

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Interested on how this turned out for you? I just put my CCW's on the cobra, 18x11 rears 335/30/18's I'm getting some rubbing on the inside on most bumps and turning as well. I believe my stock shocks are to soft for the H and R race springs.

I'm actually changing out the shocks tomorrow. But I won't be able to test it out yet because there's still a lot of salt on the roads.
 

mr. b_98GT

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I think you will solve your problem with the stiffer shocks. I had some stock shocks w eibach springs in the rear and I was rubbing on the left rear slightly when the tire would get pushed up. I rolled the fenders, and it helped some, but the tire was cut into already and I needed new ones anyway. I had plans to change the springs to h&r race to raise the car, and I went ahead and changed to bilstein hd's all around w mm iso's. Car doesn't sit so low now, has a nice raked look, and I went out of town these last two weeks and took the Cobra. Drove about 750 miles on the new set up. Zero issues with rubbing now. Car also rides a lot better with the new bilstein and h&r springs.
 

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