How are FRCA compared to stock ? Will they help a V6 better than a V8?
I'd like less/no wheel hop, but without any noise. I was thinking J&M or FRCA.

 

so then whats the point of an adjustable upper rear control arm?

 

I'm sorry but I had to comment. I'm glad you can't respect other people's motorsports. It gives me one more damn good reason to continue to turn people away from your "product." I find it funny that a company that doesn't engineer any of their own product (outside of ripping off someone else's) should be able to speak about motorsports like they have any authority.

The fact of the matter is that Steeda (You know, a company that ENGINEERS their own product, not blatantly rips them off and says they engineered it) Brandon is right, there are many ways in which you can reduce wheel hop, LCA's are ONE of them. For those of us lowly and inferior motorsports enthusiasts ******** cones in a parking lot at parking lot speeds CAN'T run them without being bumped into a much higher class SO WE DON'T. Numerous people who have run them have said they made an impact on the FEEL of the car but no noticeable impact on the speed at which they completed the course. That means it is extremely LOW priority to spend money on and those of us who actually compete and know suspension know that adding them, when other viable options to reduce or eliminate wheel hop exist, is simply putting yourself in a class you wont be competitive in until you drop a lot of cash to do it.

I realize that you can't just plagiarize that idea so you can get it through your skull (since that seems to be the only way you and your company "learn") so maybe if we say it half a dozen more times you'll eventually understand WHY Sam doesn't recommend them and that it has nothing to do with the fact that he spends his weekends ******** cones in a parking lot. Then again, we can probably repeat it forever and you'd still be too dense to get it.


DTMR, the point of an adjustable UCA is to be able to fine tune pinion angle. You can do it with the UCA or the LCA's. Keep in mind that your LCA's influence A LOT of variables in Handling (what this section is devoted to) to include roll steer and antisquat. The biggest one most corner carvers are concerned with is the roll steer issue. Having two LCA's that are unequal in length not only causes the back end to follow a different track then the front (crab walking) but it changes how much steering the rear suspension contributes during body roll and it does so at different rates in each direction. That is not how I would want to deal with my car. IMO, adjustable LCA's require a lot of very precise set up and are an absolute PITA to work with. I would rather put my car up on jack stands and cuss and swear with an UCA install and have a much more painless pinion angle adjustment then have to make sure I turn each LCA half a turn (or however much) and make sure they are the same length on both sides.

 

DTMR, the point of an adjustable UCA is to be able to fine tune pinion angle. You can do it with the UCA or the LCA's. Keep in mind that your LCA's influence A LOT of variables in Handling (what this section is devoted to) to include roll steer and antisquat. The biggest one most corner carvers are concerned with is the roll steer issue. Having two LCA's that are unequal in length not only causes the back end to follow a different track then the front (crab walking) but it changes how much steering the rear suspension contributes during body roll and it does so at different rates in each direction. That is not how I would want to deal with my car. IMO, adjustable LCA's require a lot of very precise set up and are an absolute PITA to work with. I would rather put my car up on jack stands and cuss and swear with an UCA install and have a much more painless pinion angle adjustment then have to make sure I turn each LCA half a turn (or however much) and make sure they are the same length on both sides.[/QUOTE]

Damn is that stuff about UPR true?? Thanks for the input! Then if I do get them ill get nonadjustable ones with an adjustable upper rear control arm

 

http://www.corner-carvers.com/forums...=25368&page=23

Start at post 897 and read on from there. I'm sure if you sent Kelly at BMR a PM asking about his opinion he could probably point out a number of their product that has been ripped off (K-member comes to mind). So yes, it's true.

I tend to not be belligerent about it since it tends to get people removed from forums (especially when they are site sponsors) but I have gotten really sick of Sharad's comments about how supposedly inferior autocross is as a motorsport. It's really uncalled for and it's not like he has any room to really talk about inferiority.

That is the way most folks do all their control arms... Non-adjustable lower's and an adjustable upper.

 

A few miscellaneous thoughts . . .

I'll stay out of the autocross class-legal aspect at least for now.

I'd give exactly the same advice as what Sam has made (and would have even if I hadn't read it) - to lower the car first and see if you need to do more. Sneak up on your solution.

I'm also going to give the benefit of the doubt to Sharad as a competitor being separate from any aspects of the business side. By way bof example, he has suggested Koni yellows, which are not carried by UPR.


With that out of the way,

The pinion angle that you need (optimally, and primarily for the straight line stuff) is dependent on the firmness of the control arm bushings. Most spherical pivots can be assumed to be rigid. Starting from the softish OE rubber bushings, as you go firmer you need less pinion angle. Hence there is some sense in having firmer-bushed LCAs adjustable. This is a separate effect from any pinion angle change resulting from lowering the car.

Lowering the car also changes where you're operating along the anti-squat curve. Anti-squat is not a fixed parameter; it varies slightly with ride height, and starting from the OE position this drops slightly as the car begins to squat. Not by a huge amount, but it's still inherently a slightly unstable situation. I'm not trying to imply that "unstable" means "dangerous", "unpredictable", or anything like that, just that this condition is not as "geometrically self-limiting" as you'd prefer (IOW, you have to wait for the rear to squat a little more before the anti-squat curve starts to work for you). Lowering by up to about an inch fixes this - puts you closer to the "bottom" of the very gradual U-shaped A-S curve to start with - and makes the anti-squat % rise from the get-go as squat begins to happen.


I do happen to have adjustable LCAs on my car, as a rather recent mod occasioned by a couple of the OE LCA bushings showing signs of deterioration (Currie units, FWIW). They are not on-car adjustable, and it is entirely possible to get them mismatched for length even if you match them to their location-specific OE LCAs that you're removing. Fortunately, if this happens you get a big clue in that the steering wheel is no longer centered while driving straight, with one full thread's worth of "error" being clearly noticeable. Easy enough to fix.

I can also tell you that since they aren't both ends rod-ended there is a little contribution to rear roll stiffness. Not quite enough to force me to reset my rear bar down a notch, but it's there even after tweaking the poly ends for less of this. The application of even small amounts of power hits just a little quicker - and the car reacts to road conditions just a little more forcefully. I suspect that any of the poly/spherical LCAs behave similarly. True rod ends won't add the stiffness (unless bound up for any reason) but will exhibit the other attributes.

I'm not much into the straightline stuff, but I would get into wheelhop on pavement that was damp/wet enough or at autocross starts on the right (wrong?) pavement conditions. I'm not lowered (that's whole 'nother story), and now I'm not getting the hop under generally similar conditions. I admit that I haven't tried really hard to get into hop since, because having it gone for the way I do drive is good enough for me.


Norm

 

Norm,

General question. What do you hear, feel, and see when a LCA joint (stock, poly, rigid) is going bad?

 

You might feel a little directional instability under throttle, under braking, or swapping between the two.

Rod ends will rattle once you've pounded enough clearance in the ball-and-socket joints.

A rubber bushing will visibly crack from being overloaded or over-deflected, as can poly.

All of these things should be considered "wear items" in a car that gets driven hard from time to time.

You may not notice all of the symptoms.


Norm

 

umadbro?

I've never said anything legitimately critical of autocrossing. My dad was autocrossing before I was born, and he instilled that interest in me from the time I was a young boy. I'm sure everyone in this thread knows I was just taking about jab at Sam with that comment I made. Sam and I go back and forth. If he wants to dish it out, he can take it a little too. He's a big boy. If you're offended by a playful comment on the internet, well... there's not much I can do for you.

And since you're throwing rocks in a glass house, ask Kelly at BMR what he thinks about Sam. Where do you think I got the comment about parking lot racing???


PS- Here's me enjoying your supposedly inferior motorsport. It's a lot of fun!







SteedaBrandon- Did you see the article I wrote about Steeda suspension in 5.0 Mustang Magazine? Matt & Steve bolted a set of LCAs onto my car between rounds at Sebring last year. The difference in handling was day & night. LCAs aren't just for controlling wheel hop. They also improve axle control in the corners and over bumps.

http://www.mustang50magazine.com/tec...k/viewall.html