Thanks again to all who've replied with pics and info. RX7Carl, thanks for the insight-I never really saw any *good* pics of the RB bar, and couldn't tell that the material was rolled at the lip/edges. I was under the impression that it was made from flat aluminum plate and beveled at the edges, not rolled. Carl-you really seem to know what you're talking about-do the mounting points on the firewall need to be closer to the center of the car for better lateral stability? That would be my guess. Any hints/tips/tricks/ideas to help strengthen up the rear suspension mounting points?
Slowautoxr-OMFG, that's yet another kick-*** idea that I may be able to incorporate in my bar-camber adjusters! I'm going to have my strut tower plates CNC plasma'd (and probably milled to finished off the slots now), so I should be able to "borrow" that idea and save almost another $200. Thank you! BTW-what kind of carbs are those, ICH series webers? That is truly a unique set-up. I'm having problems downloading this morning, I'll have to check out the pics a little closer in the next few days to figure out how I'll pull it off.
Morey987-raised strut towers? Was your car lowered that way? I've channeled trucks before, but I'd personally be afraid to cut into a unibody car myself to lower it. Unique idea though.
I greatly appreciate any comments, pics, ideas, or suggestions from anybody, even constructive critisism. I'd hate to have to make more than one of these (for myself) if I don't have to. Keep the pics and comments coming, along with any fresh new ideas to build into a strut/suspension bar. Thanks!

-Adam

 

It's a racing beat kit from what I can gather. Helps eliminate the bottoming out.

 

You mentioned that you want left/right handed threads for adjustability, right? Doesn't that describe the MRC bar? I just re-read their description to be sure, and it sounds like it's exactly what you are requesting. Am I missing something?

Sounds like you're on you're way to building a very nice ride...

 

it's pretty much the same thing, but i think instead of the turnbuckle, hes wanting to thread both ends of the tubing. thats what i got out of it.

 

Exactly. I want to be able to add pressure between or away from the mounting points. To adjust the one I'm going to build, you'll only have to loosen one left-hand-thread jamb nut and one right-hand-thread jamb nut from each side of the center tube (which will have machined wrench flats) and manually rotate the center bar itself, leaving the strut tower plates fully attached to the strut towers. Even with the "turnbuckle" style pictured on ReSpeed's website, you'd still have to remove the bar (at least one end completely) to adjust it. I want to build mine with both positive and negative possible adjustments for the main reason being I don't have much experience with strut-sprung vehicles. Most of my suspension work and modifications have been performed on dual wishbone (double "a-arm") type front suspensions and I'm not exactly sure of the repercussions of exerting pressure outward on the strut towers or away from them and the adverse affects either will have. I'm sure this adjustment would (one way or the other) affect camber gain/loss entering or exiting corners a great deal more than just a non-adjustable straight center bar/tube, or even an adjustable bar that can only be adjusted off of the vehicle.
Personally, I don't really care if it takes me a year or more to get my suspension 100% dialed in to my exact preferences-but by having every little possible aspect adjustable ensures that I WILL eventually reach my goal and remain satisfied with it's performance for years to come. Sure, I could buy a non-adjustable bar or something other than what I desire, but as engrossingly **** as I am about the small details like this I would NEVER be satisfied and continually wondering what would be possible with this or what impact this feature would have on my suspension system. I don't NEED it, but then again I don't NEED the car either. I just want it...

 

This is not a true statement. The turn buckle and threaded tubes ends are LH and RH threaded. Break the jam nuts loose and turn the turn buckle to adjust.

If you move forward, and have cad data on your parts. I would be happy to quote the laser work for you. I know you mentioned plasma but I can beat ANY price on laser or plasma in mild steel sheet and plate. Plus you wont have the nasty edges with laser bits.

-billy

 

Just remember is some classes the triangle connection back to the firewall is a no-no and the bar can only go between the two strut towers.

 

I'm sorry man, I saw the pic and the only adjustable part I could see was located on the driver's side so I assumed this was the case. Again, I apoligize. I shouldn't have assumed. I figured the fully adjustable LH and RH threads were incorporated into the firewall ties, which is also what I plan to do with mine. I'll send you a PM with the info to discuss the laser cutting. I ran a CNC plasma for over a year and a half, so I know exactly what you're referring to when you mentioned the "nasty edges".

TG-thanks for the reminder. I had also noticed the warning on ReSpeed's website, but I don't plan on racing this car. I realize I'm sinking quite a bit of money into just a high performance street machine, but I've fallen in love with this little car and don't want to set any type of performance limitations on the suspension. I'll not compromise more streetability than I can afford to lose in the engine compartment (only adding a few pounds of boost with a 7" Camden supercharger), but I believe my goal of high eleven second 1/4 mile times will be easily reached when an agressively street ported and supercharged four port early 13b (from my SE with 12a side housings) finally finds a new home between my GS's strut towers.

My suspension will be a totally different story though-with no shortcuts, compromises, or generic components at all to hold it back from it's full potential. I can live with the harsher ride I'll inherit from a low 35- or 40-series 17" tire sidewall, the higher spring rate I'll have with the additionally cut RB springs (at least until I get my ride height within the range I'm shooting for to figure out the spring rates and free heights of the coils to order with ReSpeed's front and rear coilover kits), and the stiffer dampening qualities of the Illumina's higher settings. By running all adjustable components, I'll be able to change the dampening/rebound rate of the struts/shocks, the ride height, caster/camber/toe settings, swaybar preload, and other adjustments to smooth out the ride if I wish to drive it up here to Pittsburgh (or where ever else I may be) to bring it to work for a week or two, then change it back to more performance-oriented settings for the winding country back-road driving it'll see more of around home. To put it bluntly, I'm not going to build the car to be legal in any certain racing class, I'm going to build it to fit my driving style and to be more compatable with the types of roads I most often commute. Don't get me wrong-I'm not saying I'll be street racing it, but I may have to push it to the limits once in a while to help me avoid the other idiots on the road...

Kentetsu-thanks man. I've already put quite a bit of blood, sweat, and tears into this project and I've got much more to go, and even more money to spend on it!

Again, thanks to all who've shared opinions and ideas! Keep 'em coming!

 

why dont you check out the strut tower bar from rx7.com

 

rxfo, thanks for the compliment. That RB bar is heavy steel. Exactly, going to the center creates the best triangulation possible, and as a bonus, you have the mount for the hood latch there already. But that causes small but manageable access problems for mx. To stiffen the rear suspension mounts I would look to seam weld the areas and maybe add some gussets and/or doublers where the links mount. But the rest of the chassis will still flex a bit. One area that you might want to seam weld also is the c channel that runs inside the car left to right behind the seats.

Maybe if you really exerted pressure you might affect the camber, but thats something you should be able to adjust if you run plates anyway.

tg, thats why the IT car has a straight across bar, triangulated isint allowed in IT.

 

Thanks for the info, Carl! My storage boxes are already out of the car as is the carpet, so I'll have to break out the welder once I get a bit of time off to spend back home and weld up the "c" channel and gusset the rear suspension mounts in critical areas. The only other option I could think of as I was disassembling the SE was to add a roll cage and incorporate the rear four cage mounts directly over the factory sub-frame/body-mounted link bar mounts to further increase COMPLETE chassis rigidity. I don't really plan on racing the car, only a few drag strip passes at the most, and I don't plan on it being fast enough to require a 'cage at the strip but am seriously considering one for the additional strength and reduced flex it could provide.

I don't have much experience with unibody cars, either. I'm used to full-framed domestic cars and trucks, so I'm not really sure where the common roll cage attachment points are in these vehicles. For my purposes, I believe tying the front subframe/suspension into the rear suspension/subframe would be the best possible placement for a 'cage. I'd use DOM .090" 1.5" OD tubing and build a six-point 'cage with additional attachments to each rear upper shock mount if I were to do this, unless one of you guys has a better alternative.

One more thing, does anybody have any experience experiementing with "subframe connectors"? The subframes on both the front and rear of these cars look to be integrated with the body (unlike most older domestic "unibody" cars with bolt-in subframes-Camaro's, Fox-bodied Mustangs, etc). Has anybody sucessfully attempted to weld in additional braces between the front and rear-extending the entire length between them? I may have to ditch my "full look" interior idea to keep the car at 2400lbs if I add the 'cage and subframe connectors...Thanks again for the help guys!

-Adam Collins

 

Well if your serious, your not that far from St. Louis. This guy builds the best cages for a 1st gen Ive ever seen. http://www.izzyscustomcages.com/Home.html He's a 1st gen guy whos expanded. He's a member over on Mazspeed and a good guy from my dealings with him. My road race car has a Kirk cage. Its ok, like any bolt in cage, ala autopower. Legal but not that great. ISC does cages but not to the saftey, engineering and quality of Izzy's. If I ever get back into road racing, I'll build a new car and I will tow the shell up there to have him do the cage even though ISC is only down the road. No offense to Mike at ISC, hes a good guy and does good work, but Izzy's cages would make me feel safer.

http://www.izzyscustomcages.com/MJYP2CageInstl.html

I dont think anyone has tried a "subframe connector" as theres really no frame to tie in. Seam welding is the trick to adding stiffness to these unibody cars. Search the net for seam welding. Theres lots of examples to learn from, especially the rally guys. They beat the hell out of their chassis.