13GetThere

Any opinions, or experience with either the Bilstein B6 or B8 dampers in the S197?
I'm looking at the B12 kit which includes Eibech Pro Kit springs and B8 dampers, or Ford P springs and B6 dampers.

Bert

I have no direct experience, but I have heard they are well respected among the road track crowd; the monotube construction stands up well under relatively severe duty

those matched sets seem like a good idea, because that ensures that the damper is well matched to the spring, and I think they even come assembled with the upper strut mount? I am not sure if this is the lowest cost approach, but certainly convenient

I wonder what is the difference between the B6 and B8 dampers? guessing the 8's have more damping and better matched to the stiffer Eibach springs

dusman59

I run the Bilstein B6 with Ford P springs and have had zero issues. I used the GT500 upper mounts. I don't track my car so I installed the mounts 180 degrees out from what a GT500 would have been normally installed. This would give your alignment less negative camber. Otherwise You can use more expensive upper mounts for more adjustment. I also cut the rear bump stops about an inch as they where hitting and it made a noticeable harsh ride. All was perfect after the bump stops were modified. I did install a Steeda panhard bar even though the rear axle was not off by much after lowering. Traction will be improved with the right tire along with lower control arm brackets. I have zero wheel hop issues.

SilrBult

I recently installed a Vorshlag Street Pro [ Bilstein dampers, Ford Racing "P" springs and Vorshlag's castor/camber plates ] suspension package on my '14 GT. I want to wait until I am able to get at least one autocross completed before making a more in depth review, but since the subject of Bilstein dampers has come up I'll give my preliminary observations. Before getting into the dampers it's important to know that not all GT's have the same stock ride height. One of my friends had a '13 GT with the track pack option and mine is a base model. I bought a base because I didn't want to pay twice for a performance suspension. My family and friends simply think I am cheap. He had his car in my shop one day and with both cars sitting close to each other it was quickly apparent that his car sat about an inch higher than mine. A quick check with a tape measure confirmed this. It's important to note that we both had the same size tires and wheels, 9x19 with stock size 255x40x19 tires so a true apples to apples comparison. The point being that if you want to lower your car and the vendor says the springs will lower it an inch or whatever it would be good to know what they were starting with. I wound up using the stock rear springs since with the rear "P" springs the car actually sat a half inch lower in back than it did in front. The front "P"'s lowered the front about 3/8 of an inch from stock. I don't want to get into a lot of detail here about ride heights, suffice to say that having the rear lower than the front involves more than just aesthetics. We can discuss spring rates later too if anyone is interested. The Bilsteins used in this kit are the same ones specified for use on '05-'10 model SN197 cars or at least they have the same model #s. The front struts come pre-assembled which is a nice convenience. Vorshlag's castor/camber plates are some of the most expensive on the market, but I think they are very well made and designed. They also offer more adjustment than most others and include the lower mounts. Now to the Bilsteins themselves. They are stronger than any twin tube I've seen. Twin tubes generally have a 22 mm strut rod, Bilstein's are 40 mm. They are also an inverted design and don't bottom out. No bump stops are required, nor would stock type ones fit. Monotubes have a larger diameter piston than a twin tube of equal outside diameter. As we know from relatively simple math a small increase in the diameter of a circle results in a rather large increase in it's area. Simply put a monotube reacts more quickly to even small movements. The downside is that they do tend to ride more stiffly over broken pavement and expansion joints. I think if I ran over a paper clip I could tell you what size it was.They actually ride better on wavy pavement as they really don't float like stockers. The brake dive and rear squat under acceleration is greatly reduced as is rear wheel hop. I have driven it somewhat aggressively [ 7-8 tenths ] on some lightly used curvy and hilly roads and even with stock size [255x40x19] Pilot Sport AS3+ tires the grip is impressive.

759Rider

Well it seems I am in good company. Bilsteins and P springs. I also run the GT 500 hats, but in the "normal" position, as it's just not a daily.

The shocks are amazing. I have always been a Bilstein fan. The price is higher, but the the quality is unmatched.

I am considering the "K" or Steeda coils, as the ride height seems like it could come down. That said, I really can't imagine it handling much better. And I appreciate the extra wheel travel on the road.

My consistent takeaway from driving this thing is that it jut needs more rubber. Car is just too big and heavy for stock or mild tire size upgrades. (with respect to all my auto-x friends)

:-)

SilrBult

I agree about needing more tire. I only intend to do 2-3 autocrosses a year and I drive the car in all four seasons [ not in snow, at least so far ] so even though the all season AS3+ tires give up some grip the convenience of a square set up for tire rotation and cold weather capability makes it worthwhile for me. If I could find a really good deal on a set of 19x10 lightweight forged wheels I think I would have to go for it. Anyone who wants to read a really in depth write up on SN197 series Mustangs should go to the forum section of Vorshlag's web site and check put the work they put in on their 2011 Mustang. They are currently doing a similar test on their 2018 S550.

13GetThere

759Rider, are you running the B6 or B8 Bilstein dampers on your P springs?

759Rider

Geez. I didn’t know there was a choice.

Here’s the PN. MPN# 35-128717

Thats the number for use with the GT500 hats.

:-)

SilrBult

35-128717 is the part # for '05-'10 SN197's. These are the struts used by Vorshlag on their Street Pro suspension kit. They offer both the Ford Racing "P" and "K" springs as well as springs from Eibach for use in this kit. The "P" springs are the ones they prefer. These struts are 1.25 inches shorter than the stockers and work well with most lowering springs.

dusman59

I am not sure about the rear being lower than the front but using the P springs my stangs front sits lower in the front than in the back.

m05fastbackGT

According to Bilstein's website description, part # 35-128717 is the B6 performance strut assembly designed to be paired with the OE factory spring. Therefore, I don't know how Vorshlag can claim the Bilstein B6 dampers are 1.25" shorter than the stockers and work well with most lowering springs, when Bilstein claims otherwise? At any rate, here's the product description link below from Bilstein's website.

https://www.bilstein.com/us/en/produ...76034165599341

dusman59

Well maybe they will work with the OEM springs as well as a lowered spring. Having a 1.5 in shorter strut matched with a shorter spring seems to make a better combo. All I know is they work well with my lowered springs.

m05fastbackGT

To make certain we're on the same page, are your Bilstein B6 struts/shocks 1.25 inches shorter than OEM struts/shocks or the same? Also is your part# 35-128717? Just need to make certain these will match up with Eibach Pro Kit Springs which lower the front suspension by approx 1.3 inches and rear suspension by approx 1.4 inches.

dusman59

Yes the part# 35-128717 is what I used and matched with GT 500 mounts. There is another part number for use with other mounts not sure of that part number. The difference is at the top of the shaft has a difference shoulder. Strut height would be the same between the two part numbers.

m05fastbackGT

The only other part# that I'm aware of is F4-VE3-C871-HD.. From my understanding part# F4-VE3-C871-HD is the old part# and 35-128717 is the replacement/updated part number? I also have GT500 strut mounts paired with my current Koni sport adjustable struts/shocks and Eibach Pro Kit Springs. Therefore in your opinion, would part# 35-128717 match up with Eibach Pro Kit lowering springs?

dusman59

I don't see any problem with the springs you are using. Just make sure you trim the rear bump stops. Vorshlag offers your springs with Bilsteins.

m05fastbackGT

Although Vorshlag offers the Eibach springs with Bilsteins, they prefer paring them with Ford Performance P springs.. Why, I don't know? Anyhow, when the Koni sport struts/shocks were installed, the stock bump stops were replaced with Eibach bump stops designed for their pro kit shocks, which I assume are shorter than the stockers