jimq

Has anybody bought one of these bars off of evilbay? Seems like a pretty good price but wonder about the quality and if it really is CF.
thanks

http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT

apw964

Hey Jim,

I picked one up about 2 weeks ago. The build quality is great and the installation was a snap. I haven't had a chance to see if the car handles any differently yet as it's up on stands having some brake work. I suspect that the carbon may flex a little under compression and will not be as beneficial as a titanium or aluminum equivilant. It looks nice though :-)

Andy

GG Allin

I bought one too. Looks nice. Haven't driven the car yet though. Can't beat $150

Gus

I bought one that has the carbon fiber cross bar - but the attachment points and set up are different -
Have used in autocross only (to date). Seems to help stiffen up the front end less lateral flex in turns -
Have not noticed any adverse affects.

Syd B.

Jim, I bought/installed one last summer and aside from looking great, I can definitely feel an improvement in handling when cornering aggressively. Otherwise, you won't see much difference in ride. By the way, the install took all of 10 minutes. I suggest that you install it over the carpet, which means that you only have to drill very small holes in the carpet for the bolts. If you ever remove the strut, you won't even notice the holes.

garrett376

I gave in and got an aluminum one from Vertex off eBay for $125 or so - it looks like the original type as seen on the C4RS. I don't notice anything different from a handling aspect, and this is on a car with stiff springs, stiff shocks, and race tires with very stiff sidewalls. I can't imagine there would be any noticeable difference on a street car especially with squishy street tires. But, I got it because if the factory felt it necessary for their race cars... it made sense enough to spend a bit to try it out! It will just stink if one side gets hit, then it will certainly screw up the opposite side as well - all the more reason, to me, NOT to have it on a street car!

Heirsh

Good point about it messing up the other side if you get in an accident.

Assumption that only tension is on this device...

Use a piece of wire? If one side of the car is smacked it wont cause damage to the other side. If there is only tension it will work just as well.

thoughts?

MarkD

These make a difference in those flimsy cabs... like mine.

Seight

I bought an aluminium one from ebay last summer as well and I can tell you it made a massive difference to my C4. The turn is is MUCH sharper and understeer significantly reduced on fast corners. I think it may be more beneficial to a C4 than a C2 due to the inherent nature of 4-wheel-drive.

Cheers
Alex

CraigyB

looks just like the one I installed recently on my C4. Absolutely marvelous. So much more precise on the turn in.

robmug

The look the same as the ones we sell at ACP (http://www.advancedcarproducts.com/p...d=Strut%5FP964) in which case they are indeed pure carbon tubes and VERY strong.

The feedback we get is universal - much better turn-in, even when they were just buying it as a cosmetic enhancement

jimq

Thanks for all the feedback guys. Havent spent any money on the car yet this month so might as well start today

garrett376

...not to be a sceptic, but a stiffer front end lends to more understeer

Syd B.

I've posted this once before, but here is a great write up on the subject of Strut Braces by Ken, a fellow Rennlister from a few years ago. I think it provides an excellent explanation of what a strut brace will do for your car.

Well let me put my 2 cents worth in. If you think about what stresses are induced into the front end of a car during a hard turn, the stresses are not applied evenly between the front tires. In a left hand turn the cars weight is shifted to the right side of the car and as in any turn you experience a deceleration, which also shifts weight forward. So in a left hand turn the right front tire has both roll weight shift and rear to front weight shift loading that tire mort than the front left. The problem with this is that the right front strut tower has a tendency to flex toward the outside of the car changing the camber of the tire. You now have a differential camber between the two front tires affecting the handling of the car in a hard turn.

The strut brace (also known as a camber truss) is there simply to shift the stresses that the camber tower (on the out side of the turn) cannot handle without flexing to the other camber tower. The whole purpose of the camber truss is to tie the strut towers together so the stresses that the tower in the outside of a turn are transferred to the inside tower. With the towers tied together the camber of the tires does not change and the car handles better in a corner.

About now the normal question is won’t both towers flex in a parallelogram motion? The answered is no because unless you are running racing slicks on a well groomed track your tires will loose traction before the stresses will cause both tower to flex toward the outside of the turn.

With all of this being said, it is apparent that the stresses that are exerted into a strut brace are all tension (pulling between the tower) and not compression. In other words the forces on a strut brace is simply the force that the strut tower (that is on the out side of a turn) cannot hold on its own is transferred to the inside tower through tension. Understanding this it should be apparent that spherical ends, aluminum bar etc. have no difference in the operation of the bar. The issue of strength is simply; if the bar does not tear apart in a hard turn then it is doing its job. The alloy and design of the KLA bar is actually overkill for the forces it holds. You can actually lift the entire weight of the car using the bar, brackets and spherical rod ends.

I would agree that if the bar were under compression that we would need a bigger bar but once you understand the geometry of the car and how the forces are applied that all forces are in tension instead of compression.

Bottom line is that any strut brace that ties the towers together will all accomplish the same result. Some just look sexier than others

Finally, Eric, the flex in the KLA bar when you pull up in the middle has no relationship to how well it works because no forces are applied to the bar in that manner. If tou can pull on one end of the bar and streach the bars length then you have an issue. The KLA bar is designed th handle many time the force that a street car in a hard turn can put into the bar.

I hope this helps.

Ken

garrett376

Someone should put some sort of tension and compression meter in the middle of a bar, and some sort of flex measuring device to monitor the shock tower movement to see if it truly makes any difference. Until then, I guess we go on theory!

Along the lines of the theory and the reason for my doubts (remember I do have a bar on my race car!!! ), sidwalls of street tires are so soft that they inherently change camber way before the shock towers start to flex - come to think of it, the compliance in the stock rubber A-arm bushings, in the rubber top shock mount/bearing, and in the tires themselves, will make more of a camber change before the sheet metal of the shock tower moves enough to actually cause a camber change beyond that which has already occurred.

While we're thinking about it, the force that is applied to the outer tire would cause an increase in the negative camber in the heavily loaded outer front tire. Now wouldn't that increase in negative camber be a benefit because the contact patch is better maintained on the road surface???? Sounds like the strut bar is a disadvantage!

But then again, that's theory, too!