Front End Upgrades

[Goose428]

I just got done making the rear end feel much better, and I am at a point where I am happy with the rear end of my car (2008 Bullitt). Now I am wondering how to improve the front.

I have maximum CC plates, FRPP shocks and struts and run a street friendly alignment. My car has 153k on it, so some of the equipment may be worn.

So far, a couple things have been on my radar. My goal here is to improve front end/steering feel, improve turn in and gain grip.

Front Lower Control Arms:

It seems the most cost effective way to gain front end response would be to just replace my front lower control arm bushings (front and rear) with stiffer units. As I understand, this will be more of a "feel" thing. Would it be reasonable to expect slightly more tire contact patch under corning+braking load due to less deflection from the stiffer busing? Is doing this worth the trouble? The Ford Racing front lower control arms have popped up as well, however these seem like a waste of money to me as they don't change the suspension geometry at all (i think?).

Bump-Steer Kit
Just curious if anyone has anecdotal evidence of a bump steer kit helping, lot's of mixed opinion on them. Would love to hear (good and bad) about your experience with them.

Steering Shaft
This caught my attention. Any thoughts?
http://www.griggsracing.com/product_info.php?cPath=4332_4309_4328_2000_3050&products_id=310

This car is mainly used for canyon carving, but I also track a couple times a year and autocross 15x a year.

I look forward to hearing your responses, thank you

 

[Norm Peterson]

If your car isn't lowered, or is only lowered very mildly, there is no need for correcting bumpsteer in any car that still sees street driving. Track only, at the pointy end of timed competition with contingencies at stake - you'd probably want to do this no matter where the ride height was at.

There is some advantage to replacing the front control arm bushings in terms of toe control under heavy braking, but you'll get noticeable improvement in that just going to the FRPP arms from OE arms that only have 30,000 miles or so on them. I suspect that the FRPP arms use slightly firmer bushing material than the GT got on the production line.

Front LCAs by themselves won't change the suspension geometry. That takes lowering or a change in ball joint stud length.


What's your definition of a "street-friendly" alignment?


Norm

 

[Totheboards]

I'm curious what you did with the rear suspension?

 

[Goose428]

Hi Norm, thanks for the reply.

I was wondering if someone would ask me to clarify on my alignment....Sadly I lost the spec sheet, but I want to say that it is around -1.5 camber, I can't remember the toe. My car is lowered 1 inch in front. I told the alignment guy (Mike Maier) to give me an alignment that won't ruin my tires but will be decent in autocross.

I think the FRPP control arms may use a slightly firmer bushing, however if you look at the pictures the bushing still seems to be an all rubber unit. That, combined with the fact that I am paying for an entire control arm (something I don't need) makes me think that I could get more of what I want for cheaper by just changing the bushings to some not-so compliant ones, no?

https://www.maximummotorsports.com/Front-Control-Arm-Bushings-2005-Mustang-P1203.aspx

https://www.maximummotorsports.com/Front-Control-Arm-Bushings-2005-Mustang-P1203.aspx

I'm thinking something like these ^ bushings on the stock control arms would give me better results than the FRPP arms? Again, just kinda thinking out loud here, looking for more input....

https://www.americanmuscle.com/ford-front-controlarms-0511gt.html

In the rear end I added a maximum panhard bar, FRPP jounce stops and FRPP 302S rear lower control arms. These all helped to eliminate a lot of the midcorner "skip" when going over a bump.

 

[Norm Peterson]

The FRPP catalog is pretty specific about the front arms using stronger ball joints. Between that and a widely publicized tubular control arm failure, I went with the FRPP arms. I'd already decided that if/when I wanted or needed stiffer bushings that I'd find ways to stiffen the FRPP bushings. If that didn't work (or work well enough), I could still do the burn-out-and-replace-with-poly thing. Obviously I wouldn't be able to go the other way.


BTW, I think you meant to link the 220 part number for one of those MM bushing sets.


Norm

 

[Norm Peterson]

Duplicate post because the site never took me out of the reply screen after hitting /Submit'.


Norm

 

[Norm Peterson]

One more duplicate post because the site never took me out of the reply screen after hitting /Submit'.


Norm

 

[Norm Peterson]

Another duplicate post because the site never took me out of the reply screen after hitting /Submit'.


Norm

 

[Norm Peterson]

Yet another duplicate post because the site never took me out of the reply screen after hitting /Submit'.

Never had this problem when the forum was using vbulletin . . . had to reopen the thread in a new window to find out what had happened and try to fix it. Grrrrrr . . .


Norm

 

[Goose428]

The FRPP catalog is pretty specific about the front arms using stronger ball joints. Between that and a widely publicized tubular control arm failure, I went with the FRPP arms. I'd already decided that if/when I wanted or needed stiffer bushings that I'd find ways to stiffen the FRPP bushings. If that didn't work (or work well enough), I could still do the burn-out-and-replace-with-poly thing. Obviously I wouldn't be able to go the other way.


BTW, I think you meant to link the 220 part number for one of those MM bushing sets.


Norm

Hi Norm,

Thanks for the reply. So i'm guessing that you like the FRPP arms? Did you notice a big difference? I'm thinking that maybe between the FRPP control arms and griggs steering shaft I could get some nice front end improvements. Or maybe the FRPP arms with the stiffer maximum bushings.

Let me ask you this....Are the FRPP arms (besides the bushings) any better than the stock front control arms?

EDIT: Just found these. Any thoughts? https://www.americanmuscle.com/whiteline-antidive-kit-0510.html

And yes, looks like I sent the same link twice. thanks

 

[Norm Peterson]

So far, I'm happy enough with them - installing them did manage to eliminate most of a minor stability issue I'd had under hard braking (0.9+ g) from speed (120+). Near as I can tell, the metal part of the arms themselves looks to be the same. But I didn't take any measurements (including thickness) to see if there was any stiffness or strength improvements hiding where a quick glance wouldn't see them.

I don't think the OE arms themselves are in any way 'bad', and there's only so much can be done structurally once the general outline has been determined. They have bending strength in the right direction, without needlessly adding weight to add bending strength in directions that don't need to be as strong.


AM's video on Whiteline's "Anti-dive" kit didn't tell me what I needed to hear. Anti-dive is a matter of side view suspension geometry, and to make more anti-dive you'd need to raise the rear pivot of the control arm. Which is neither mentioned nor apparent in the pictures (you'd look for something like the inner holes in the yellow bushings not being concentric with the outer diameter of the poly . . . something like this). On Whiteline more generally, they do appear to have products that look deeper into the proper application of polyurethane than most, and this is a good thing.

Incidentally, any actual geometric correction to anti-dive or camber is likely to end up requiring bumpsteer correction as a companion modification. Either of those geometry changes will move the ends of the steering arms (and the outer tierod pivot points) vertically while the ball joint height remains constant. It's analogous to installing tall ball joints where the ball joint height moves and the outer tierod pivot height doesn't.


Norm

 

[ddd4114]

AM's video on Whiteline's "Anti-dive" kit didn't tell me what I needed to hear. Anti-dive is a matter of side view suspension geometry, and to make more anti-dive you'd need to raise the rear pivot of the control arm. Which is neither mentioned nor apparent in the pictures

I was wondering this too. Since the subframe mounting points are unchanged, I don't see how it's possible to have any significant impact on anti-dive without eccentric bushings. Otherwise, you'd need to angle the arm downward when viewed from the side, and I can't think about how you would do that without a structurally questionable redesign of the arm.

Unless I'm misunderstanding the description, they're getting caster adjustment by pivoting the arm about the front bushing by using the provided offset washers on the rear bushing. That would push the wheels forward, which would increase caster, but that seems like a strange way to do it. I would also think that would load the front bushing strangely, but I guess it's a pretty small angle. It would also increase wheelbase and decrease track width albeit by a small amount, but it still seems undesirable for just a caster adjustment.

Back to the original question, if any of the bushings are worn out, I would definitely replace them. That would help any car feel more responsible and predictable. I'm not convinced that aftermarket control arms are worth the risk, so I would just stick with something made by Ford (or Ford Racing). Outside of new bushings and ball joints, you're not going to get much performance advantage.

I agree with Norm that if you don't have a specific reason to get a bump-steer kit, I'd skip it. It's only made to correct a specific problem and will not provide a magical grip or handling benefit. Also, I have never heard of people replacing their steering shaft for a performance improvement. It sounds like snake oil to me.