Requesting suspension setup assessment

[BmacIL]

Interesting. If vertical links are working properly they'll only be noticeable when you're accelerating or braking at least moderately or hard. They resist torsional movements of the knuckle.

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[Roadway 5.0]

Out of curiosity, what are your camber settings?

Obviously camber has nothing to do with bounce, but I run the same damper and spring combo with a full-stiff rear swaybar and it takes deliberate action to break free in a turn.

I love your attention to unsprung weight reduction, by the way; well done.

 

[Norm Peterson]

Interesting. If vertical links are working properly they'll only be noticeable when you're accelerating or braking at least moderately or hard. They resist torsional movements of the knuckle.

I'd like to know the thought process behind adding rear suspension compliance for road racing as well. The only reason I can offhand think of would have more to do with driving style than anything mechanical.


Norm

 

[Bull Run]

Out of curiosity, what are your camber settings?

Obviously camber has nothing to do with bounce, but I run the same damper and spring combo with a full-stiff rear swaybar and it takes deliberate action to break free in a turn.

I love your attention to unsprung weight reduction, by the way; well done.

Here's my current alignment spec

Front Left Front Right
Camber -1.4 -1.4
Caster 7.8 7.0
Toe 0.01 0.00

Rear Left Rear Right
Camber -1.3 -1.3
Toe 0.21 0.01

Note: I originally didn't have front left strut centered when installing the camber plates, so it was at a state where caster was worse and the alignment shop wasn't able to get the camber within factory specs. Since I had free alignment check deal, they were able to get the camber within specs after I went home and adjusted the left camber plate. Mike gave me some street alignment suggestions, so once this is done, I'll take the car to a place that'll adjust camber plates and adjustable toe links to get the caster and rear toe more even.

Thanks, getting light wheels and ditching Pirelli P Zeros made a huge difference, it was almost like driving a whole different car.

 

[Bull Run]

Interesting. If vertical links are working properly they'll only be noticeable when you're accelerating or braking at least moderately or hard. They resist torsional movements of the knuckle.

At least vertical links are relatively cheaper and easier to install than dampers. If they don't help or help enough, I'll try the adjustable dampers. This is the first time I'm going all out on suspension mods, and finding that I do like a firm ride.

 

[Roadway 5.0]

Here's my current alignment spec

Front Left Front Right
Camber -1.4 -1.4
Caster 7.8 7.0
Toe 0.01 0.00

Rear Left Rear Right
Camber -1.3 -1.3
Toe 0.21 0.01

Note: I originally didn't have front left strut centered when installing the camber plates, so it was at a state where caster was worse and the alignment shop wasn't able to get the camber within factory specs. Since I had free alignment check deal, they were able to get the camber within specs after I went home and adjusted the left camber plate. Mike gave me some street alignment suggestions, so once this is done, I'll take the car to a place that'll adjust camber plates and adjustable toe links to get the caster and rear toe more even.

Thanks, getting light wheels and ditching Pirelli P Zeros made a huge difference, it was almost like driving a whole different car.

Sounds like you’re in good hands.

Adjusting your rear toe should noticably improve your overall handing; the way it sits it is quite a bit off. I’m eager to hear how the new bits and alignment work out for you.

 

[Bull Run]

I spent last few days paying close attention to how the car handles over various road conditions. At this point, I think that Pro-Action fixed dampers are more than capable enough to handle the current setup since the car doesn't oscillate after going over bridge expansion joints and speed dips. I can feel the unevenness driving over the same road in the CRV (family car), although not surprisingly, in a more muted way. So at this point, I'm thinking that the "bounces" that I'm feeling are not really bounces, but rather increased road feedback (not sure if this is a correct term) due to firmer suspension. I drove cars with worn shocks before and this doesn't feel anything like that. I'm more than willing to deal with the extra feedback in exchange for flatter cornering, braking, and better steering response.

Anyhow, FedEx tracking shows that polyurethane vertical links will get here on Wednesday. I'll throw them on as soon as they arrive, and post the results after driving around. Steeda's website also states that polyurethane version is recommended for handling while more expensive Delrin ones are recommended for drag racing applications. One lesson to be learned here is that just because a part's more expensive doesn't mean it's best for all situations...

 

[BLSTOIS]

I spent last few days paying close attention to how the car handles over various road conditions. At this point, I think that Pro-Action fixed dampers are more than capable enough to handle the current setup since the car doesn't oscillate after going over bridge expansion joints and speed dips. I can feel the unevenness driving over the same road in the CRV (family car), although not surprisingly, in a more muted way. So at this point, I'm thinking that the "bounces" that I'm feeling are not really bounces, but rather increased road feedback (not sure if this is a correct term) due to firmer suspension. I drove cars with worn shocks before and this doesn't feel anything like that. I'm more than willing to deal with the extra feedback in exchange for flatter cornering, braking, and better steering response.

Anyhow, FedEx tracking shows that polyurethane vertical links will get here on Wednesday. I'll throw them on as soon as they arrive, and post the results after driving around. Steeda's website also states that polyurethane version is recommended for handling while more expensive Delrin ones are recommended for drag racing applications. One lesson to be learned here is that just because a part's more expensive doesn't mean it's best for all situations...

I just did nearly an identical suspension setup what you have (I have J&M Spherical links and stock PP wheels with P-zeros) and finished it all up last week, and the first few miles I thought I felt bounce like you describe, but after a bit of driving, its just actually being able to feel the suspension articulate, unlike stock when the slop and bushing deflection mutes all those feelings.

 

[Norm Peterson]

"Bounce" is more about displacement - how far the suspension moves after encountering a bump or heave in the road. "Firmness" is mostly about the sensation of force involved as the suspension moves (relatively slowly) and comes from the springs and bars. "Harshness" is about the forces associated with much faster suspension motion or excessive movement that results in bump stop contact.


Norm

 

[Bull Run]

Steeda vertical links (VLs) with polyurethane bushings came in yesterday, and I swapped them out on the same day. I'm happy to report that they made a noticeable difference in taming the rear and I've hit the sweet spot of having a track-ready suspension that's still comfortable for DD use.

Observations

1. After installing the VLs, I drove over to some side roads that I know to have a rough surface with cracks and bumps. The car responded well going over cracks and bumps, which verified that the issue wasn’t with the dampers since the car didn't bounce. New vertical links didn't have issues with handling cracks and bumps, either.

2. The effect of smoothing out the ride was even more noticeable on the highway, and the car still reacted well to going over bridge expansion joints at around 80 MPH.

3. I couldn't do same left turn onto the highway ramp at full speed today due to other cars being present. However, I was able to go through a roundabout (early morning with no cars around) at high speed, and the car felt well planted.

The lesson learned here is that while spherical bearings are great, there is such thing as too much of a good thing, especially when it comes to public streets and highways with less than perfectly even surfaces. The upgrades were designed to improve how suspension reactions to the road and it did just that.

I want to thank Mike at Steeda and folks on this forum that provided valuable advice and knowledge. This is the first time I've ever done any serious suspension/chassis mods. Even as the 4 banger version, this is far the heaviest Mustang that I ever owned, yet it feels much more nimble than the past ones.

Top unit in the picture below is the BMR VL with spherical bearings and the bottom is the Steeda VL with polyurethane bushings. Both are well built and felt solid, unlike the flimsy stock ones. BMR VLs held up well and the bearings are still nice and tight. They found a new home on my family friend's GT that only has BMR CB005 and Ultralite Liner Springs as suspension/chassis upgrades. I haven't had a chance to drive the GT since the swap, but he reported a noticeable improvement in handling.

Steeda VL as installed

 

[Coyote Red]

I've done CB005,06 with SVE progressive springs & BMR camber bolts. The vertical links are next for Coyote Red.

 

[Bull Run]

I've done CB005,06 with SVE progressive springs & BMR camber bolts. The vertical links are next for Coyote Red.

Nice stance! How effective were the camber bolts? I need to check with my friend to see what were the alignment specs after he lowered his GT.

 

[Coyote Red]

The BMR camber bolts can't help toe and twice I've gone to two different Firestone shops and they couldn't give me front camber past -1.1 or -1.2 ? Bolts aren't the answer for these S550 platform ponies. The rear camber was set at -1.5 left and -1.7 right? I am getting discussed at myself.

 

[BmacIL]

The BMR camber bolts can't help toe and twice I've gone to two different Firestone shops and they couldn't give me front camber past -1.1 or -1.2 ? Bolts aren't the answer for these S550 platform ponies. The rear camber was set at -1.5 left and -1.7 right? I am getting discussed at myself.

That is odd. With your drop you should easily be in the -1.5ish range.

 

[Bull Run]

I figured out where some of the uneven steering is coming from. During high speed turns, I start to slide on my seat and find myself using the steering wheel to hold myself up, which makes it difficult to steer.

I believe a seat upgrade needs to be next. I set in Recardos in my friend's GT350R and found the back to be tight as I weightlift and have a fairly wide back. I see that Corbeau A4 seats have a wide option. Has anyone used these seats or any other Coreau seats?

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