(note: i also posted this in the road racing forum bc as much input as possible will be very useful)
Ok, here is the deal, i am in school getting my race car performance/welding degree. I am about to begin production on an number of suspension bars (f&r strut bars, rear lower tie bars, etc) due to the lack of aftermarket support for good products at fair prices and that there arent any at all for many makes (ie preludes and such). I will of course be making them for the integras, civics, and all the usual makes also. But here is my question...for gsr/itr/si's there are two ways i could mount the bars, using the factory studs for the stock bars (itr/gsr/si) or from the strut tower itself. Now i will be producing bars for the other model integras and civics that do not have these holes...so i will have to make the bars that mount to the strut tower anyways. These two types of bars mount in close proximity to each other, so i am not positive on whether it will make that big of a difference, but if it comes to my attention that the bars that mount to the strut tower work better, i will only produce that model. The bars are still in the planning stages now, but i have gotten quotes on the flanges that will be cnc'd and from different metal supply warehouses, so things should be coming together fairly soon. And if you have any suggestions and or questions concerning these bars, feel free to ask. TIA

 

my response in the other thread:
"my thoughts on this subject are this...from decent amt of information i know about material strengths and suspension theory, i know it is relatively minute compared to many people, especially those that work for companies and do testing on bracing and other strength charictersitics of different vehicles or whatever the case may be. but the basic theories i have decided to base the bars on is this: 1. the straighter the bar, the less it will flex, perfectly straight being the best way to go imo 2. brackets for strut bars are overlooked many times and they themselves need to be braced (ie an "L" bracket needs lateral support in order for it not to flex or flex as little as possible (no flex being best of course) 3. the straight tube of any such strut bar needs to be attached to a bracket as close to the mounting points as possible, to reduce "possible flex" whether it would happen or not. using these guidelines i believe i can produce bars that will perform well, bc that is priority number one
Another topic that comes up quite frequently is what shape and diameter tubing should be used, as well as what material. My personal opinion (feel free to chime in as i know that there are people who know more about this than i do) is that a round tube will result in the least flex theoretically, when measured against other shapes of the approx same size and thickness, so a round bar is going to be what i will be using. Also mild steel is going to be my first option as far as a material goes, due to the fact that it is easier to weld, and has very good strength characteristics. One problem that will be a concern is the weight of the mild steel in comparison to aluminum. I have taken this into account, and me along with some help from my uncle (a civil engineer) will decide what will be the lightest as well as the strongest diameter/thickness to use and have take up as little space as possible without sacrificing stability. If anyone thinks that they would be very beneficial to my design and production process would like to talk to me personally just let me know, and i will not let your help go unnoticed or unawarded "

 

anyone's thoughts?

 

any input would be appreciated

 

in terms of a strut bars you want to have straight stiff tubing with NO JOINTS, solid mount only. also I would think that Triangle shaped material would be better than round tubing. Speaking of triangulation....in order to have a more solid and effective strut brace you need some sort of triangulation in order to tie in properly (like the Carbing 3pt)

 

also if you are going to make it out of steel I suggest using at leaset .040" thick tubing

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dirtyd463 &raquo;</TD></TR><TR><TD CLASS="quote">in terms of a strut bars you want to have straight stiff tubing with NO JOINTS, solid mount only. also I would think that Triangle shaped material would be better than round tubing. Speaking of triangulation....in order to have a more solid and effective strut brace you need some sort of triangulation in order to tie in properly (like the Carbing 3pt)</TD></TR></TABLE>

yes, a solid design has already been established, actually it was never in question. However concerning the triangulation of the bar, i will likely offer such a bar bc people like it, but until I can tell or see proof that it does more than look pretty, i will probably not use one on my personaly vehicle. My thinking behind this is that the firewall is little more than sheetmetal, and for the triangulation it would need to be more solid or be part of the chassis itself

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dirtyd463 &raquo;</TD></TR><TR><TD CLASS="quote">also if you are going to make it out of steel I suggest using at leaset .040" thick tubing</TD></TR></TABLE>

the plan is to find the smallest/lightest diameter/thickness combination of tubing, yet still sacrifice no strength qualities, this will be figured with some basic math on my part

thanks for the replies

 

well here is the way I see it is with the triangulation.......look at it like this...say you have two pieces of flatbar standing on end. By themselves they are very unstable but if you add a cross brace it makes it more stable (strut brace) now if you add another point to that that ties into an opposing structure

look at it like the two pieces of flatbar are stanfding on end and the exposed end is pushed against an intersecting piece and the brace ties the three pieces together

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and with strut bar material...honestly my best suggestion is to make it out of an Aluminum extrusion (kindof like some sort of slide track or a double walled aluminum)

not a very good explanation but I am shure you are smart enough to figure out what I am saying.....a triangel is incapable of collapsing upon itself

and if you are thinking of the normal mounting point on the firewall being too thin...find a different location to mount it

 

finding another location for the mounting would probably be the best thing to do, however you have to put this into consideration...does the chassis flex enough from the front to the back of the vehicle enough to warrant the extra wieght of the triangulation pieces? we all know that the chassis flexes from side to side, otherwise strut bars wouldnt be needed at all. I am just saying to consider these things for arguments sake, or to play the devils advocate or whatever. if i throw out all these scenarios whether false or correct, it helps to work out the bugs, so bear with me. I am discussing the more technical aspects of this right now with some materials and automotive engineers, depending on what the values for load transfer from one strut tower to the other (supposing there was a solid non flexing crossmember welded there) we will try and decide on a material to use, but i think that i will be going with mild steel for now, just bc it does have good strength qualities, it welds easily without having to be heat treated afterwards, and even though its heavy, using some math (and help from qualified engineers) we can figure the lowest possible weight the bar can be, based on the smallest dia/thickness, like i said before. so hopefully the finished product will be fairly light, but more importantly than the X amt it weighs, is how well does it work, and that is what im focusing on right now for the most part.

 

more input would be appreciated

 

you shouldn't have to heat treat aluminum after welding it....as long as you do not overheat the material while welding you should be fine......especially if using an aluminum extrusion

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dirtyd463 &raquo;</TD></TR><TR><TD CLASS="quote">you shouldn't have to heat treat aluminum after welding it....as long as you do not overheat the material while welding you should be fine......especially if using an aluminum extrusion</TD></TR></TABLE>

well according to others i have talked to, as well as things i have learned you do sometimes have to heat treat it, johnny mac put it well by saying "If you weld the aluminum (assuming 6061 alloy) or the 4130 Chromoly, you need to heat treat after the weld is complete to regain the ductile crystal structure that was transformed by welding. Mild steel does not need to be heat treated after welding." But of course this is not always the case, anyways i will not have everyday access to a tig welder.

this is major payne btw im just on caseys computer

 

anymore helpful input??

 

up for more suggestions/input