Question about lowered FC front suspension
11-12-07, 02:46 PM
#26
Exactly! Bringing the strut tower base inwards...
Restricted rules just end up meaning you can't move suspension mounting points on the chassis.
Then there is nothing stopping you from tightening it by pulling the strut tower tops together a bit.
11-12-07, 04:25 PM
#27
That would be one serious turnbuckle to pull the chassis in more than a few millimeters!
If I didn't have rules and I wanted the cheap way out I would adapt some GSL-SE struts from an FB and put the big brake kit(FC) on them. That way you could use the GForce Eng. strut spacers and get the roll center back up to a reasonable height. You could leave the chassis alone and just have to figure out a way to mount the early ball joint to the later control arm.
Come to think of it that may even be legal in EP...
If I didn't have rules and I wanted the cheap way out I would adapt some GSL-SE struts from an FB and put the big brake kit(FC) on them. That way you could use the GForce Eng. strut spacers and get the roll center back up to a reasonable height. You could leave the chassis alone and just have to figure out a way to mount the early ball joint to the later control arm.
Come to think of it that may even be legal in EP...
11-12-07, 04:31 PM
#28
Lives on the Forum
But unless you change the relationship between the strut and the upright then all that'll do is give you more camber (just like moving the strut top with a camber plate. Then you'll just end up having to adjust it out, leaving you with the exact same geometry as before, that was my point. Just making the strut mounting "ears" longer won't help anything, you need to change the angle between the strut and the upright to make a difference.
Changing the lower pivot point doesn't have to change the track at all, and with the much larger negative camber gain in the rear these cars have a natural tendancy to understeer, but you can tune anything out with the right combination of springs and sways. Changing the lower pivot point gets you closer to the stock geometry, whereas changing the strut tower gives you something else entirely. There's more to the geometry than just the angle between the strut and the arm, the angles of each play a role in the roll center location. I think you're maybe misunderstanding, all that's being done is to take the lower pivot point between the strut and the arm and move it down without changing the inner pivots at all.
One of these days I might investigate making an adjustable roll center correcting outer pivot that'll work with the stock S4 control arms and stock uprights. I wonder how many people would be interested if I had them made in a batch and sold some? I have no idea how much such a thing would cost though.
Changing the lower pivot point doesn't have to change the track at all, and with the much larger negative camber gain in the rear these cars have a natural tendancy to understeer, but you can tune anything out with the right combination of springs and sways. Changing the lower pivot point gets you closer to the stock geometry, whereas changing the strut tower gives you something else entirely. There's more to the geometry than just the angle between the strut and the arm, the angles of each play a role in the roll center location. I think you're maybe misunderstanding, all that's being done is to take the lower pivot point between the strut and the arm and move it down without changing the inner pivots at all.
One of these days I might investigate making an adjustable roll center correcting outer pivot that'll work with the stock S4 control arms and stock uprights. I wonder how many people would be interested if I had them made in a batch and sold some? I have no idea how much such a thing would cost though.
11-12-07, 07:22 PM
#29
One of these days I might investigate making an adjustable roll center correcting outer pivot that'll work with the stock S4 control arms and stock uprights. I wonder how many people would be interested if I had them made in a batch and sold some? I have no idea how much such a thing would cost though.
11-12-07, 08:28 PM
#30
Lives on the Forum
That was basically the plan, but maybe make some extras and hopefully do it so that there doesn't need to be any modifications to the stock upright. I'd also be making sure to properly engineer it to make sure that it's strong enough for any normal loadings that it'd encounter.
11-12-07, 10:29 PM
#31
Well, DAMN!
iTrader: (2)
Join Date: Nov 2003
Location: W. Orlando
Posts: 533
Likes: 0
Received 0 Likes
on
0 Posts
Black, I think you were talking to me in #28. Just to clarify my thoughts, moving the strut top mounting location further inwards towards the engine will change the relationship between the lower arm and the strut housing (simplifying terms here to avoid confusion)amongst other things (lever arm, etc). LOL, When I made my suggestion, I wasn't addressing roll center, just changing the angle the between the lower arm and the strut housing thereby delaying positive camber on a lowered vehicle.
Your idea to create a roll center pivot is, in actuality, the PROPER way to correct the camber and roll center issue in one shot. So instead of all the welding, I'll be on line to pick a set up! I was told that creating a corrector for the FC was just too time consuming to even be worth it? How long will this take to create?
~Mike
Your idea to create a roll center pivot is, in actuality, the PROPER way to correct the camber and roll center issue in one shot. So instead of all the welding, I'll be on line to pick a set up! I was told that creating a corrector for the FC was just too time consuming to even be worth it? How long will this take to create?
~Mike
11-13-07, 10:31 AM
#33
Well, DAMN!
iTrader: (2)
Join Date: Nov 2003
Location: W. Orlando
Posts: 533
Likes: 0
Received 0 Likes
on
0 Posts
Roen,
Just found out they're for sale through AWR and work on the S4, and not the S5.... and all along I was told that you couldn't add roll center correctors to these cars. That's what I get for simply listening and not researching for myself (kicking myself in the ***).
~Mike
Just found out they're for sale through AWR and work on the S4, and not the S5.... and all along I was told that you couldn't add roll center correctors to these cars. That's what I get for simply listening and not researching for myself (kicking myself in the ***).
~Mike
11-13-07, 10:50 AM
#34
Lives on the Forum
I recall seeing a picture of their "roll center block" in the classifieds at one point and it was just a spacer that goes between the ball joint and the arm, so it does nothing. There probably won't ever be anything for the S5 arms because they're one piece with non-replacable ball joints.
That may not have been them, but since they don't show pictures or give a description on their website I can't say for sure.
That may not have been them, but since they don't show pictures or give a description on their website I can't say for sure.
11-13-07, 12:46 PM
#36
It's real easy to make a roll center correction block for these cars. Since we don't have a tapered ball joint you just need to make a piece that plugs into the ball joint location on the spindle. That piece has to have a place for the ball joint to plug into the bottom of it and clamp.
I've made them before but I won't sell them for legal reasons, too much to lose against the minor gain if one breaks. I can dig for a drawing and Rockwell hardness numbers if somebody wants to make some themselves.
I've made them before but I won't sell them for legal reasons, too much to lose against the minor gain if one breaks. I can dig for a drawing and Rockwell hardness numbers if somebody wants to make some themselves.
11-13-07, 12:57 PM
#37
Well, DAMN!
iTrader: (2)
Join Date: Nov 2003
Location: W. Orlando
Posts: 533
Likes: 0
Received 0 Likes
on
0 Posts
Looks like AWR has stopped making the roll center blocks due to the amount of lowering that customers were doing exceeded the reccomended AWR height. They could no longer provide an accurate roll center height, which makes complete sense when considering that your roll center changes as you change the ride height.
That is one of the reasons AWR has gotten more elaborate which their newer suspension pieces. I didn't even want to know $.
Jgrewe, I'd love to have that info, thanks, but It's looking like I'll have to churn out some specific numbers based on my desired ride height
Black, I'm still kinda confused as to why you're feeling these roll center blocks will not work. Your thoughts?
~Mike
That is one of the reasons AWR has gotten more elaborate which their newer suspension pieces. I didn't even want to know $.
Jgrewe, I'd love to have that info, thanks, but It's looking like I'll have to churn out some specific numbers based on my desired ride height
Black, I'm still kinda confused as to why you're feeling these roll center blocks will not work. Your thoughts?
~Mike
Last edited by BFGRX7; 11-13-07 at 01:03 PM.
11-13-07, 07:39 PM
#38
Lives on the Forum
What the picture was only spaced the ball joint relative to the arm, not the ball joint relative to the upright, so the geometry didn't change, just the shape of the arm did.
I'd also like to see said information.
I'd also like to see said information.
11-16-07, 05:50 PM
#40
I havn't forgot, I may just do a quick drawing on wordpad it's so simple. I called my friend that treated them for me to see if he remembers what the Rockwell #'s were. If he gets back to me with that before I find my detailed drawings I'll doodle something on a napkin and take a picture of it. IIRC the first version I drew was on a napkin anyway
11-18-07, 12:23 PM
#41
Rotary Freak
Join Date: Dec 2001
Location: chandler, AZ
Posts: 2,402
Likes: 0
Received 0 Likes
on
0 Posts
Real racing = Real money
It would be nice if they would knock a bunch of those out though and tell you what height to run it at, but then the original owner wouldn't have the advantage he paid lots of $$ for to have Yaw Power develop that project for.
It would be a little wrong for Yaw Power to knock off a bunch of these and sell them on Ebay looking at it from this perspective wouldn't it.
My guess is that is why they don't have more info and a price for the suspension- it was someones competitive advantage they paid $$ to have Yaw Power develop.
It would be nice if they would knock a bunch of those out though and tell you what height to run it at, but then the original owner wouldn't have the advantage he paid lots of $$ for to have Yaw Power develop that project for.
It would be a little wrong for Yaw Power to knock off a bunch of these and sell them on Ebay looking at it from this perspective wouldn't it.
My guess is that is why they don't have more info and a price for the suspension- it was someones competitive advantage they paid $$ to have Yaw Power develop.
Sadly with rule changes being implemented this season, the suspension is not legal in EP. We have made multiple sets, and the price is actually more affordable than the "guesstimated" $3k. However, we are currently focusing on fuel injection and hesitantly put suspension engineering on the back burner for the time being. If somebody is truly interested in a setup please PM me or send an email to info@yawpower.com.
11-21-07, 10:18 PM
#42
I have a good enough picture for anybody that would have the capability to make the part but I drew it on 'paint' and the file is too big. Any help with getting it posted? I know there is a way I just have never needed to.
My buddy that treated it for me is out of town for turkey week. Hopefully he'll have the hardening specs for me when he gets back.
My buddy that treated it for me is out of town for turkey week. Hopefully he'll have the hardening specs for me when he gets back.
12-03-07, 05:50 PM
#45
Old [Sch|F]ool
We could deflect the under floor U-channels by at least 1/2" just with a prybar against one of the heat shields.
Wouldn't take much of a turnbuckle to yank things way out of shape...
12-07-07, 10:34 AM
#50
Lives on the Forum
I never said I didn't.
It'll be at least this summer before I can even look at it in any detail. An S5 system would be basically limited to what is pictured above, no replacing the joint.
It'll be at least this summer before I can even look at it in any detail. An S5 system would be basically limited to what is pictured above, no replacing the joint.