99Z28RS

Should i even bother with buying the Chrome-Moly BMR or should i just get the regular one, i figure it cant be much of a difference.

Judd

iTrader: (1)

I don't think the STB works all that great on our cars. I didn't notice squat on mine when I put it on. I'm lazy and don't really want to remove it, it might help a bit but I don't think a cro-moly bar would be worth it. JMO

jimmyblue

iTrader: (11)

For this application "Chrome Moly"
is just hype.

People like 4130 chrome moly for
automotive fabrications (like roll
cages and other larger pieces) for
two reasons - strength/weight
(high tensile strength means you
are allowed a thinner-wall tube)
and the fact that you can weld it
up using a variety of fillers that
includes mild steel MIG wire.

However, if the Chrome-Moly one
comes with a nice decal then it's
probably worth it ;p

The BMR site shows they use a
thinner-wall tube in the chrome-moly
version, likely offsetting any gain
in strength from the material. Unless
you go for their "Extreme" STB, which
seems kind of pricey. I bet the thin
wall on the C-M standard brace saves
you a couple of ounces though....
In the immortal words of J. C. Whitney:
"Increase performance! Improve fuel economy!"

BurnOut

iTrader: (1)

I honestly don't know if the cro-mo piece has any advantage over the non-cro-mo piece; I personally have the cro-mo one on my car.

They say that the STB helps reduce cowl shake in our cars; though I have to admit that I never drove mine hard before installing the STB, so I can't make any before/after comparisons...

VipZ28

iTrader: (4)

I think it's mostly a weight thing... I know my BMR ChromeMoly LCA's are lighter than my friends regular ones...

2FAST4U

I have very piece of BMR product on my car and have chrome moly on any part that had that option. When I have my roll bars installed it will be chrome moly. But I am tring to loss weight even if it is 1lb over 3 or 4 parts! You need to think about every thing you want to do to your car drag,autox,cost,weight,ect...

talonis

I made my STB out of wood and duct tape and it's worked great <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

CM seems overkill for that piece. I'd say if you have infinte wealth it'd be cool, but otherwise you can probably spend the money on upgrading other weaker points on the car.

scot

A 2point on a 4th gen car can make very little difference because the shock towers are very strong side to side. On 3rd gens with struts it's a different story, but 4th gen cars need help front to back. A 3point STB works far better than the strongest 2point.

Boo Yeah

I live in a very hilly area. and i can attest they make a big difference, or it did on mine. I can notice the car itself feels more rigid up front and the steering feels a little tighter. We did test the two pieces and the cromoly takes more to flex. We bolted it to a empty front clip a friend has from a swap, and the clip did not have one side so we pulled up on it, while i myself 5'8" 195lb could move the normal one, i could not make the cromoly deflect at all, but with two we could flex it, then i got my cromoly. Another thing to factor in is that the cromoly one we tested was about 10 months old and the other was brand new.

Elliswon

The youngs modulus or in other words the stiffness per cross sectional area of material of cm and mild steel or any steel for that matter are for all practical purposes the same. A stb is a brace, hence the name. While cm is stronger than mild steel, the purpose of a brace is to stiffen not necessarily to strengthen. Any difference in the stiffness of two different steel bars is a consequence of design i.e. section thickness, etc. not of material choice.

As for a strut tower brace making the car "feel" better, so does having a Victoria's secret model in the passenger seat. But she, like the stb, doesn't do much for the handling of the car.

Boo Yeah

i just know what the seat of my pants tell me, part of it could be the age of my shocks and what not. The car seems to corner alot flatter as well, but i know thats not what a stb would do. I just know thats what it feels like

99Z28RS

Well ive decided to hold off on getting an STB al together and get an Eibach-Pro-Kit along with KBDD SFC's for christmas, this should be an ok combination for now until i get more Chee$e

scot

Elliswon gave an excellent description of the difference between the perception of improvement and actual difference in lateral acceleration potential, braking g-load, steering turn in, ect. Unreal amounts of money can be spent on the car that does improve the perception of solidity and capacity while not making the slightest improvement in how fast the car will negotiate a road couse.Any 2 point STB will improve the fact of and the perception of higher performance less than a 3 point.Neither will make a significant difference in lap times.

Elliswon

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Boo Yeah:
<strong>i just know what the seat of my pants tell me, part of it could be the age of my shocks and what not. The car seems to corner alot flatter as well, but i know thats not what a stb would do. I just know thats what it feels like</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">You're right, a stb has no direct effect on the roll of a car. In fact if they really increased the lateral g capability of your car, it would roll more not less since the roll angle is a function of the roll stiffness of the car (not the chassis stiffness) the weight, CG height, and lateral g.

If SOTP was accurate then CART and F1 wouldn't need all that expensive telemetry that they have.

The fact is that the buttometer is just not accurate enough to measure the performance of an automobile reliably.

I've been modding cars for 20 years, have an engineering degree and flew tactics and weapons test missions for the Air Force and when someone tells me this mod or that mod "feels" faster, I tune him out. Statements like that are a sure sign that individual just doesn't get it. It's the Placebo effect pure and simple.

It's not intended as a flame, but if there was one thing I would do if I owned a site like this is ban the word feel.

trackbird

iTrader: (4)

I agree with your lack of respect for product reviews that involve the word "feel". But, there is one thing I didn't feel after adding my 2 point BMR (steel, not chromoly) STB.....Steering wheel shake (over pot holes, railroad tracks, etc). I won't say that the car handles any better (I have done no testing to back that up), but when the car does not seem to be "hinged at the dashboard" it inspires confidence in the driver and a comfortable driver is a fast (or is a potentially faster) driver. I won't tell you that an STB will make you a roadracing "hero", but it will do good things for reducing dash squeaks and rattles and eliminating steering wheel "shake" over bumps, etc.

Someone mentioned that these cars don't need a 2 point as much as the older strut" cars. The springs are actually mounted under the strut tower brace mounting points and that is where the chassis load is concentrated (the older cars had springs mounted inboard of the shocks) and that is still a potential source of chassis flex.

Anyway...with all that said. It's one of the least expensive mods for these cars and it sure can't hurt anything to support the chassis....expecially with the increased chassis loads of stiffer springs and shocks. Just my opinion (others may not agree). Happy corner carving....

Boo Yeah

I personally have not raced cars very long, but on that note my father has raced his whole, flat track for harley, stock cars, drag cars, boats, he even held the worlds water speed record in 1973. But anyways he agrees that the whole car up front feels stronger more on track, though it still likes to groove walk, it no longer has as much bump steer as before.
Now correct me if iam wrong, but i think it is positive camber when the top of the tire sticks out farther. Well anyways if you take a corner and your tower moves causing positive camber would this not reduce traction, causing increased handling. And also if there is less weight on the inside of the tire, then due to disperment of the weight on the tire and the angle of the suspension would this not cause more role. Sorry i don't have computers to tell you the exact difference but by yourself one, you shoulod have enough money and tell me if you can't tell a difference. So far everyone who has ridden in the passenger seat says they can tell a difference, even my fiance. I never told her she asked me what i did to make the damn doors rattle less and the front to feel stiffer.

This was not meant as a flame but a perterbed response.

hammerhead

iTrader: (1)

I, um, experienced a tighter front end after putting on the STB. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> It really surprised me- I wasn't expecting or looking for it. That prompted me to put on SFCs soon after & I've been a happy camper since. Even if STBs don't work, (which I strongly believe they do) they're cheap and they look cool <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
I just took mine off and noticed that the paint has rubbed off around where the edges of the STB bases rest on the STs from shifting slightly & I had the nuts torqued down bigtime. The bases never sat flush, though, so I'm making some steel gaskets to put on the STs to create flatter surfaces for the STB bases.
But back to the original question, no, I wouldn't think CM is necessary- but now you've got me looking into them, dammit! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

<small>[ December 16, 2002, 01:12 PM: Message edited by: hammerhead ]</small>

Zeta

Does someone know someone who has a hotchkiss style STB?

If so removing a bolt from one side and replacing it with a wood dowl [something fragile] will give a person a really good idea of the deflection between those points.

So if there is someone here willing to try this, it would end some of the puzzlement about this topic.

Boo Yeah

it really works, and the hotchkis is only for those who will have to take it off often it is not any stronger.

Elliswon

Boo Yeah,
You missed my point. I'll restate it. Because something feels better is not proof that it is better. I am not saying that a STB will or will not improve the handling of any given car. I am saying you have not proved your case to me. If you wish to prove your case go out to a parking lot somewhere and set up a skid pad and measure the lateral g with and without the STB. All you need besides a large piece of asphalt is a piece of chalk, some string, a tape measure and a stopwatch. If you can repeatably measure more lateral g with the STB than without you will have ended the controversy and endeared yourself to many a STB vendor. It's called the scientific method and it's what distinguishes modern society from medieval society with its alchemists and leeches.