Lets talk about aftermarket suspension parts

[Scargo]

Are you sure this is a Subaru? My vague memory suggests it is not. Note the trailing arm attaches differently. Either way it looks like a strut suspension so whatever those guys were trying to accomplish is just irrelevant to the 818. Except the impressively solid look of it all.

Do Luck’s Time Attack GDA Impreza.

http://www.modified.com/features/mod...u-impreza-wrx/

[samuel]

I have been reading a lot of comments about replacing bushings on different suspension bits. I check out the ones I have and they don't look damaged or worn. Is there any thing else to look for or am I concerned about nothing?

Thanks, Sam

[Ravendas]

I have been reading a lot of comments about replacing bushings on different suspension bits. I check out the ones I have and they don't look damaged or worn. Is there any thing else to look for or am I concerned about nothing?

Thanks, Sam

Well, it depends on your donor. If you have a 2007, you're probably ok. Mine is a 2003. Since it has been my daily driver for quite a while, I've already replace a some of bushings with poly. My left LCA bushing was actually broken and leaking about a year ago, so I've replaced those as well. I say just do a visual inspection, and if you're fine with the condition, just run with it. I'll probably be replacing all of the bushings because I'm already there, so why not? I'm in no rush and I'd rather do it right the first time.

[Ravendas]

Here's my take. I don't have my kit yet, but I think you need to think of it as "Daddy's seen to it". I would not be tweaking the suspension unless you know exactly where it's at as a completed, driveable unit. I don't think the suspension is suspect. It has proven otherwise. It's NOT a WRX.

Edit: What I'm trying to say is the car handles beautifully by all accounts and FFR has designed in all the geometry adjustments you need unless you start changing up things.
I find it interesting that the stock WRX KPI/SAI ( kingpin inclination) is about 15 degrees (and camber at less than 1 degree). This SAI seems huge to me and I see that the steering arm Ackerman is near 0. While Ackerman is fixed, FFR may have reduced the SAI dramatically.

I had to go lookup half the terms in your reply. SAI, KPI, Ackerman.... lots of info I didn't know.
Here's a picture that shows the difference between stock and ALK:
alk.JPG

Basically, it adds castor to the front wheels. My stock unit is blown, and leaking nasty grease, so I'd like to know the ramifications of using the ALK that I currently have on my donor on the 818. I know there's not many people finished yet, so I may be entering uncharted territory with this! But, one can't get an answer without asking a question!
Given the issues with tires rubbing already, I'm guessing this won't be doable, and I'll need to recondition my stock units (glad I saved them!). But it would be nice if someone had already attempted this and knew for sure...

[Jaime]

It doesn't just add castor, it changes the pivot plane of the lower control arm. On a stock WRX, it reduces dive. It will probably do something different on an 818. Three ways to tell:

1. Measure the suspension bits and plug numbers into software.
2. Try it.
3. Ask someone that has done one of the above.

I would stay away from parts that fix suspension problems of a WRX since the 818 only uses about half of the stock suspension parts and none of the stock mount points.

[Ravendas]

You should let Whiteline know, as they seem to think it adds positive castor...
https://www.youtube.com/watch?v=Jn-aWUFKY98

I would stay away from parts that fix suspension problems of a WRX since the 818 only uses about half of the stock suspension parts and none of the stock mount points.

Yeah, I'm thinking that as well.

[Scargo]

I had to go lookup half the terms in your reply. SAI, KPI, Ackerman.... lots of info I didn't know.
Here's a picture that shows the difference between stock and ALK:
alk.JPG

Basically, it adds castor to the front wheels. My stock unit is blown, and leaking nasty grease, so I'd like to know the ramifications of using the ALK that I currently have on my donor on the 818. I know there's not many people finished yet, so I may be entering uncharted territory with this! But, one can't get an answer without asking a question!
Given the issues with tires rubbing already, I'm guessing this won't be doable, and I'll need to recondition my stock units (glad I saved them!). But it would be nice if someone had already attempted this and knew for sure...

Perhaps when my crystal ball works really well I would know who's ALK you are referring to and how much it changes caster. I would not go there. There is a NTE caster limit, where you cannot get the steering straight again...JK
Didn't Troy Ackerman play for the Cowboys?

[Wayne Presley]

I still wonder why everyone is wanting to modify the 818 when you haven't driven the car, let alone at the limit which is the only time you would feel the difference in these changes. I have driven both the S and R at the limit and they handled extremely good. It would go any where on the track I wanted, I could rotate the car on trailing throttle and the tail would come right back in when going to neutral throttle.

[Xusia]

I would stay away from parts that fix suspension problems of a WRX since the 818 only uses about half of the stock suspension parts and none of the stock mount points.

The number of re-used parts is irrelevant. The geometry is completely different, and therefore so are the dynamics of the suspension. The point remains, however: Those parts are designed to fix problems on a completely different car. Best not to use them unless you know for sure they are needed and what impact they will have.

I still wonder why everyone is wanting to modify the 818 when you haven't driven the car, let alone at the limit which is the only time you would feel the difference in these changes. I have driven both the S and R at the limit and they handled extremely good. It would go any where on the track I wanted, I could rotate the car on trailing throttle and the tail would come right back in when going to neutral throttle.

What Wayne said! Drive first. Evaluate. THEN fix problems (if there are any).

[Santiago]

I'm not sure this is entirely to the point of what some folks are thinking - I mean, I don't think some folks are trying to "fix" an imaginary problem. In general, I totally agree with the rule of thumb "drive first, evaluate, fix (if necessary)" so I lean in that direction.

However, "fixing" may not be on everyone's mind; they may be operating on the idea "it's awesome already, now how can we make it even better?" There are some basic principles that allow you to pursue this line of thinking: e.g. lighter is better (given equal/adequate strength), wider track is better (if you can fit it), lower cg is better (if you can manage it), and so forth. There are diminishing returns with any such approach, so the first rule of thumb is still important to weigh heavily, but it's not the only approach. I can see why some people would want to improve on what they have/will have in their hands (or least start thinking about how to improve it). Personally, I'd count myself in this category. My attraction to the 818 is not that it's great out of the box, but that it's a great platform on which to build. And by that I mean that it looks like it has core elements in place (rigidity of chassis, low overall weight, low cg, etc.) that will deliver large returns on a broad range of enhancements.

Note, I would not put something like those Whiteline bushings in this category, since they're not based off of broadly applicable fundamental principles, they're based off of specific tuning techniques to achieve goals set for a specific platform.

Best,
-j

[Scargo]

What Santiago said... Wayne, I wont argue that the car doesn't handle beautifully. It's obvious it's competitive.

However, for the same reason I could not leave my STi alone, I am motivated to have it be better for racing. Not a compromise car, not for driving to the track, but a trailered car, purely for racing.
I echo Santiago with, it's a good platform to build on. I immediately saw the potential and was excited by the fact that it was based on a Subaru drivetrain that I'm familiar with.
One area where I diverge is that I have fab and welding capabilities. I'm getting an unpainted frame. I don't feel constrained. I don't want to "try it and see if I like it" and then start modifying it. I want to get as close as I can the first time to how I envision my ultimate race car will be.
After working within the confines of the STi "box", I feel I have an opportunity to be more creative and not feel like I'm trying to make a silk purse out of a sow's ear. I sure hope Silver (my STI) doesn't hear this.

[Wayne Presley]

What Santiago said... Wayne, I wont argue that the car doesn't handle beautifully. It's obvious it's competitive.

However, for the same reason I could not leave my STi alone, I am motivated to have it be better for racing. Not a compromise car, not for driving to the track, but a trailered car, purely for racing.
I echo Santiago with, it's a good platform to build on. I immediately saw the potential and was excited by the fact that it was based on a Subaru drivetrain that I'm familiar with.
One area where I diverge is that I have fab and welding capabilities. I'm getting an unpainted frame. I don't feel constrained. I don't want to "try it and see if I like it" and then start modifying it. I want to get as close as I can the first time to how I envision my ultimate race car will be.
After working within the confines of the STi "box", I feel I have an opportunity to be more creative and not feel like I'm trying to make a silk purse out of a sow's ear. I sure hope Silver (my STI) doesn't hear this.

Given that, I'd replace the bushings with urethane but retain the stock pick up positions on the front. Then do a full rod end like I'm doing on the 818R below.

[Xusia]

I'm not sure this is entirely to the point of what some folks are thinking - I mean, I don't think some folks are trying to "fix" an imaginary problem. In general, I totally agree with the rule of thumb "drive first, evaluate, fix (if necessary)" so I lean in that direction.

However, "fixing" may not be on everyone's mind; they may be operating on the idea "it's awesome already, now how can we make it even better?" There are some basic principles that allow you to pursue this line of thinking: e.g. lighter is better (given equal/adequate strength), wider track is better (if you can fit it), lower cg is better (if you can manage it), and so forth. There are diminishing returns with any such approach, so the first rule of thumb is still important to weigh heavily, but it's not the only approach. I can see why some people would want to improve on what they have/will have in their hands (or least start thinking about how to improve it). Personally, I'd count myself in this category. My attraction to the 818 is not that it's great out of the box, but that it's a great platform on which to build. And by that I mean that it looks like it has core elements in place (rigidity of chassis, low overall weight, low cg, etc.) that will deliver large returns on a broad range of enhancements.

Note, I would not put something like those Whiteline bushings in this category, since they're not based off of broadly applicable fundamental principles, they're based off of specific tuning techniques to achieve goals set for a specific platform.

Best,
-j

When made my comments, it was in response to the use of product designed to address a suspension issue on a WRX, not about improvements based on general principles. Sorry - I could have been more clear on that.

I agree with what you've said, and I've been modifying my own car where I see fit.

[Santiago]

Oh no Xusia, I was actually thinking of the first half of your comment when I referred to the bushings being a specific tuning technique we should avoid (initially at least). I think you nailed it the first time and explained rather well why we should be hesitant to use such products. I was just trying to clarify the difference between fix and enhance.

Put differently, I could have just said I agree with you that right now for all we know those bushings are ways to fix a problem, not enhance our platform.

Best,
-j