Squaring upper control arm with chassis/alignment issue. **Help**

According to the alignment instructions and the GTS manual the upper control arm pivot is supposed to be square with the chassis. Mine wasn't. I squared it up and re-aligned the front end.
http://www.clubcobra.com/photopost/data/500/control_arm_001.jpg

This ended up putting my front wheels way to far forward in the wheel opening of the body.
http://www.clubcobra.com/photopost/data/500/control_arm_002.jpg
The LCA is also angled forward.

It's seems as if this car was supposed to have offset UCA's. Does anyone have any input on this before I invest in a set of offset UCA's?? I found some for $40 each so it's not a huge investment.

I see what you mean. The tire is not centered in the wheel well, and the coil over is not centered in the upper A-arm opening. The coil over could hit the upper A-arm when driving over curbs or raised apex's. If you move the wheel to be centered in the wheel well, won't you bias the coil over farther toward the forward member of the upper A-arm? Or do UCA's fix both problems at the same time? I don't know how important this is. Maybe one of the Panoz Engr's could comment.
I used the same alignment method that you did. I positioned the upper control arm pivot to be in line with the longitundinal frame member. My positioning was similar to yours, in that I centered the bolts in the slots. The alignment was straight forward after I set the ride height and cross balanced the car. I'll have to look at how my car's suspension makes the wheel sit in the wheel well.

....and the coil over is not centered in the upper A-arm opening. The coil over could hit the upper A-arm when driving over curbs or raised apex's. If you move the wheel to be centered in the wheel well, won't you bias the coil over farther toward the forward member of the upper A-arm?

When the upper control arm moves back, the lower will need move back too. That should keep the shock in relatively the same position. That's if you keep the same caster setting.

Gotcha. You'd need to move both.
I went and looked at my car. The front wheels are similarly placed in the wheel wells. I looked at the back wheels too. They are also not perfectly centered in the wheel wells. They are biased forward, like the fronts. The placement could be and artifact of the selected wheel base length for this tube chassis, verses the wheel well opening distances from the Espanante panels. Again the Panoz Engrs could settle this issue quickly.
I think that it's fine, unless you have some rubbing issues with the tires on the fender lip. I'd be more concerned with the alignment spec's and making sure the coilover doesn't hit any thing as it goes through it's range of motion.

It will take some major trimming of the hood to gain clearance as it sits now.

Guys... I drove mine today at VIR on the full course with the "as purchased" allignment. I simply torqued everything to spec and ran the car w/ the shocks it came with and the 350lbers up front and the 200 in the rear. I put a set of Nitto R2s on the car. The car was extremely neutral w/ only slight understeer at the limit. I feel this can be adjusted with some swaybar tuning.

I like lots of positive caster... makes the car feel very tight. Also camber was perfect as the tire wore perfectly even.

Gues I'm saying is there's no need to square up the A-arm.

VIR must have been great. I'd like to hear the details, especially the "S's."
My car's alignment as purchased was all over the place. Nothing was close to spec. Including toe, and camber. There was a lot of variation side to side too. We couldn't measure caster with the magic strings, so I don't know where that started. The alignment needed to be adjusted correctly. Sounds like yours must have been much closer to spec.

square upper arm, 6.1 caster both sides,f/l/r -2.8 camber, 1/8 toe out total, rear r .-6 rear l -.5. My arms where off too, they should be straight. I spoke to 1. engineer, and 2. the Panoz race team/distributor. 3. Nate ( whom said the cars where give alot of caster to tighten up the steering). They had to remove the set bolts to do this and cock the arms. I replaced my bolt and had the suspension setup by one of the best shops in the country. It is fine, I am running the Koni stock springs, perilli d3 slicks in 17 inch. My wheels do not hit anything, but the lower trailing arm had some interferience issues with the lower portion of the upright, shop fixed it with a bit of grinding.

I just checked my car (Series car) and it has the unequal length A arm just like the GTS cars - not at all like your picture. I guess that's why the instructions are different. The RA cars set the caster with skewing the A arm versus unequal length tubes.

I checked my car, it has equal length A-arms. As mentioned before, my alignment has the upper control arm parallel with the longitudinal frame member. I guess you are calling this "square." I have the caster set at 6 degrees.
The interesting thing is that I purchased a spare upper control arm from Gary Jones, and it's an UNEQUAL A-arm. So now I'm wondering several things.
1) Does it really matter how you get caster into the alignment? Caster is caster, right?
2) If the steering is tight with the upper A-arm "squared," should I worry about it?
3) With my alignment the wheel is essentially shifted forward. Should the car be more of less stable since the wheel is biased forward? (Remember Dodge cab forward desgin????)
I guess I need to buy another unequal A-arm from Gary to have a matched set. I'll take care of that tomorrow.

I checked my car, it has equal length A-arms. As mentioned before, my alignment has the upper control arm parallel with the longitudinal frame member. I guess you are calling this "square." I have the caster set at 6 degrees.
The interesting thing is that I purchased a spare upper control arm from Gary Jones, and it's an UNEQUAL A-arm. So now I'm wondering several things.
1) Does it really matter how you get caster into the alignment? Caster is caster, right?
2) If the steering is tight with the upper A-arm "squared," should I worry about it?
3) With my alignment the wheel is essentially shifted forward. Should the car be more of less stable since the wheel is biased forward? (Remember Dodge cab forward desgin????)
I guess I need to buy another unequal A-arm from Gary to have a matched set. I'll take care of that tomorrow.

The term "square" is used in the GTS manual and the GTS alignment instructions that I have.

Without an offset control arm, you have one of two choices. First choice is to not have the UCA square. This seems to be what most of our cars ended up with. Second option is the LCA is angled forward. This also puts the tire pretty far forward in the wheel well. To make it fit it is possible that the ride height is higher then recommended. (mine was). Either of these things can result in suspension bind. (That's the reason the GTS manual says to square the UCA). While it may not be possible to have both the UCA and LCA perfectly square with the chassis, They shouldn't be this far out.

I have 1.25" offset arms on the way. I'll let you know how they work. They aren't expensive ($40 each).

So you guys are saying that the GTS cars have shorter upper A-arms while the GTRAs have equal length? I'll have to check mine.

If you switch to unequal length arms and square it to the chassis then how do you get camber into the suspension? I don't see any other way to adjust camber other than adjusting the angle of the A-arm.

So you guys are saying that the GTS cars have shorter upper A-arms while the GTRAs have equal length? I'll have to check mine.

If you switch to unequal length arms and square it to the chassis then how do you get camber into the suspension? I don't see any other way to adjust camber other than adjusting the angle of the A-arm.


No. I believe when Blue Streak said "unequal" he meant "offset". See picture below.

I'm saying that it appears that the UCA should be offset. This would allow the pivot to be square with the chassis, have your caster correct and keep the wheel in the correct position.

Upper and lower control arms are not usually the same length as each other (unequal). This causes and increase in camber during suspension compression. This is beneficial in a turn.

http://www.speedwaymotors.com/eccStoreFront/product_images/Gif%20ChartsIllust/917-20000-CHART_L.GIF

^ Ah I see.... I'll check mine when I futz w/ the car before the next event.

Here is one of the pics of a GTWC car. Obvious offset. Maybe I should unsquare the A-arms.

Where did you find the offset A-arms?
Thanks

http://www.pd-go.com/images-pdgo/image-41566.jpg

It looks like Panoz bought a bunch or "strut type" or not offset arms and stuck them on some of the cars. There was a thread on here the said to check and see if you even had the same arms on both sides.:lol:

The pics of Btwog's car show what the UCA's should be.

I found them at http://www.speedwaymotors.com/ ***Edit*** the fricken things are made in China.:puke: Get them someplace else.

Cool... it makes sense now... if you have the offset arms you want them square because the offset gives you your caster. If you have a car w/o the offset arms you want them flared out to move the upper part of the spindle back and create yoru positive caster.

Cool... it makes sense now... if you have the offset arms you want them square because the offset gives you your caster. If you have a car w/o the offset arms you want them flared out to move the upper part of the spindle back and create yoru positive caster.

Caster is adjusted by the brake strut rod. This is the rod that comes from the firewall to the LCA. The problem with the non-offset arm is if you square it, your pushing your luck at having enough adjustment with the brake strut rod. I wouldn't want the rod ends to pull out at speed.:grinno: It would seem to me that having the UCA flared out is a band-aid for not having the right UCA. I could be wrong though. I often am.:loser: Either way, I'm putting offset arms on.:grinyes:

Guys - I'm coming in on this one late - but the positive caster was definitely dialed into the car - we saw this right away and inquired - we were told that it was a desparate attempt to get some feel of the front of the car, and to get it to turn a bit better - too tight with traditional specs...we bought 6 and they were all this way and we pretty much are running them they way they were set up and enjoying them...definitely tighten everything...we found a number of loose nuts/bolts in the TB session...

Caster is adjusted by the brake strut rod. This is the rod that comes from the firewall to the LCA. The problem with the non-offset arm is if you square it, your pushing your luck at having enough adjustment with the brake strut rod. I wouldn't want the rod ends to pull out at speed.:grinno: It would seem to me that having the UCA flared out is a band-aid for not having the right UCA. I could be wrong though. I often am.:loser: Either way, I'm putting offset arms on.:grinyes:

It's starting to get through my thick skull. :banghead: I was probably lucky that I was able to get 6 degrees of caster into the car after squaring up the UCA. I don't know how much adjustment is left in the brake strut rod. I'll have to check and see before I drive it again.
Does the off-set UCA also provide better camber changes as the wheel goes through it's range of travel? I can visualize how the off-set UCA keeps caster positive under braking and suspension travel, but I can't visualize camber. The camber is mostly a function of the different length A-arms top and bottom, right? I think that's what determines rotation planes for the wheel throughout travel.
I'm going to put the car on stands this weekend and jack the wheel through it's range of travel to see how things change. Static alignment settings are important, but it's the dynamic alignment that really counts. Determining what the car does in the corner, and why will unlock the secrets of improving it's handling.
I also think (like Jim) I'll get a second off-set UCA from Gary Jones and replace my non-off-set pair. I figure that since the series car is set up this way, there must be handling improvements to be achieved with this set up.

we were told that it was a desparate attempt to get some feel of the front of the car, and to get it to turn a bit better - too tight with traditional specs....
I've only driven the car once (40+ laps), and it seemed to turn in pretty well with the caster I have dialed into the alignment (6 degrees). My only comparison is my Z06, and the Panoz is tighter and turns in much more crisply. My Z06 has a T1 kit on it, but it still has bushings and other squishey parts in the suspension. Regardless, that's the only reference I have.
The faster I went into and through corners, the car did begin to push. I attributed that to old Pirelli's, but maybe it was really the suspension set up.
I guess I need more seat time to be able to know that the car is too "tight" as it is now.
As I said in my previous post, I think I'll change out the UCA to the off-set parts. It will be interesting to see the difference if the front end grips better, and gives higher G's thru the corner. Since I have the G2X GPS data acquision system, I can actually measure the difference in G's at each corner.

Jerry - sooo...I want to say this in a nice way...but how much have you driven the car? Have you driven it as fast as it can go?? It's a worthy enterprise to learn and understand what makes a car work, but actually more important that you have fun driving it (within the constraints of being safe)...we haven't touched any of the set up on 6 cars and are having a blast....david

Trust me...old Pirellis are a BIG factor...but we have to remember that these cars were engineered for amateurs to drive in a school...at their limits they will be tight...it becomes a challenge/art to drive them quick by whoa-ing them up smoothly and pitching them into a turn...this is very rewarding as once this aircraft carrier gets turned, its very easy to fling about at the apex and exit...fun stuff...but not a formula car - never will be...

Jerry - sooo...I want to say this in a nice way...but how much have you driven the car? Have you driven it as fast as it can go?? It's a worthy enterprise to learn and understand what makes a car work, but actually more important that you have fun driving it (within the constraints of being safe)...we haven't touched any of the set up on 6 cars and are having a blast....david
David;
I have thick skin. I can take critisism, especially constructive critisism. Basically I agree with your statement that the biggest thrill should come from driving the car, and I have great fun driving. Most fun I've ever had (with my clothes on)!!!
I have only barely cracked the book on this car. In 40+ laps (in four sessions) I didn't even come close to the cars capability. I consciencely took it slow for the first time at the track so that I could learn and feel what the car does in each corner. That's how I work a car up to it's limits. I don't want the "limits" to bite me first time on the track. No fun in that. For me, steadily working the car up in speed seems to be the safest way to learn.
It took me several years to become one of the fastest Z06's at my home track. I'm not in a hurry to get fast in the Panoz. But getting fast is part of the fun.
But that doesn't mean that I shouldn't take advantage of information and minor modifications to the car to increase it's potential. For me part of the fun is setting up the car to perform at it's best potential.
As a gear head engineer, I enjoy all aspects of the sport. I have fun wrenching on the car, I have fun changing set ups, and figuring out if that makes the car better in certain parts of the corner, etc. I have fun driving the car. It's all a learning experience, and as geeky as it sounds, learning is fun! My :2cents: :2cents:

^ I drove the car to it's limits :D I took the bitch out there and threw it into as many different situations as I could to see what she'd do. VIR is my home track and I've been running there for almost 5 years so I know the place quite well.

The new Nitto R2s made all the difference in the world compared to the shit Pirellis. I don't consider this car "large" or an "aircraft carrier" at all. Not it's not a lotus, but it corners very tight and is quite responsive compared to what I'm used to driving.

The car does understeer when pushed, but that can be countered with trail braking into a turn. It's easy to control as the steering and seat of the pants feedback from teh car is stellar.

I was able to drift the car with ease... something that was far more challenging in the Corvette.

The control arms came today. Made in fricken China.:shakehead

How long will our government fail to do anything about these uneven playing fields with these countries?

Jim, did you ever bother installing those arms?

Jim, did you ever bother installing those arms?

The arms are in and they square up nicely with the chassis. I couldn't tell you if they made any difference for not. The sway bar made the biggest difference.

I found some made in Indiana.

http://www.ubmachine.com/15-series.html

I found some made in Indiana.

http://www.ubmachine.com/15-series.html

Are you sure they are "made" in Indiana?

I just sent "Lori" an email asking whether they are made in Los Estados Unidos.

Update / Here is the response from Lori at UB Machine:

"Absolutly - We make them right here in Indiana! Made in the USA all the way!"