charliemccraney

My intake project is about done.
I don't like any of the braces on the market so I figure I'll make my own.
I've been thinking about how I want to design my strut brace. I am going to start with a 2 point brace but may end up making it 3.
I want to do it one of two ways. One is a solid 1 piece setup and the other is a 3 piece set up with rod ends at each end of the bar. In both cases they will mount to the 3 upper strut mount studs and allow normal strut adjustability. I will likely have to make a new stud clip thingy.
Which design do you think will be the best. I have seen 3 piece setups that use "clevis type" pivots and, of course, the 1 piece designs but I have not been able to find specific info on either of them. The "clevis type" designs I have seen may not have been intended to pivot. They may just be designed like that to be easy to remove.
Cost is not an issue. Even with rod ends the materials will probably be only $50.00 or so.
Also, I don't know why there aren't any that mount to the strut. Maybe I'll find out!

89_ho_rs

i just made mine. I used 3/4 thick tubing. it is strong. it cost me about 20bux. i welded it myself and cut all the tubes.

89_ho_rs

i am painting it tomorrow. going red like the car.

AM91Camaro_RS

that looks good. did you make the plates that are bolted to the towers, also?

89_ho_rs

yes i made them too. strut towers, it was a 2x2 square stock i cut to length and then cut it on an angle. the ends by the cowl are the same square stock cut in half. i painted it today. it looks nice. i will post a pic tomorrow

Charlie's87

Nice job! Here's one I made for TPI:

https://www.thirdgen.org/techbb2/sho...hreadid=116737

89_ho_rs

did you mig or tig those welds. they look tig. they look nice and clean.

92F-bird_5spd

that looks awesome. sorry to kinda hijack the thread, but exactly how did you attach it near the firewall?

charliemccraney

That looks real good.
Do you know if one that can pivot will be any benefit over one that is welded and ridged.
They are both cheap and easy to make so I may just build both and try them out.

I originaly posted this in the suspension area, hoping to get some tech and theory on this. Then it got moved.

AM91Camaro_RS

what's the point in trying to allow something to pivot? i'm not real sure that i see what you're saying but any pivoting that i can think of with a STB would pretty much defeat its purpose.

charliemccraney

That's basically my question. I'm not the greatest at wording things.
As I see it the pivoting design will keep the tops of the struts the same distance appart but still allow flex. Especialy a two point design. If this is the case then why are there so many designed this way. Is there a benefit of one over the other in different applications?

Lo-tec

Easier to remove when working on the engine.

I would make it without any pivots. Bolt the ends through the strut tower, not to the strut mounts.

charliemccraney

Why shouldn't it be bolted to the strut mount?

Lo-tec

It would be too weak. The strut mount uses a thin plate with small studs on it. You want to bolt it through the strut tower with at least a 3/8" bolt.

89_ho_rs

most of the pre-made stb's mount to the mount. i thought that if i made mine to be the same it would be right. the pivots are also in there to allow the stb to move a little but it still keeps the struts at the same distance apart from one another.which is the whole point of the stb.

I mounted it to the firewall with 2 bolts. it's not in the pic but thats how i mounted it.

charliemccraney

I plan on making a new stud plate thing with longer, stronger studs so that the strut mount can be fastened down like it came from the factory. I will then fasten the stut brace on top of the nuts that fasten the mount - on all 3 studs. Maybe it'll work maybe it won't. I'm willing to find out.

89_ho_rs

If you mount to the strut, won't the bar move the adjustments? even nuts that are tight can move. I think if you do mount to that it might move the adjustments on the strut. not sure just putting a thought into your head.

charliemccraney

I have thought about it changing the adjustment. I don't believe that it will. The fender is slotted perpendicular to the slots in the strut mount, which should prevent any side to side movement, if the clamping force of the nuts can't do that, which I think they should. I am going to slot the strut brace mounting plate so that the front to back adjustment can still be made to the strut without changing the position of the brace - to avoid any clearance issues with anything else in the bay. I will also be sure to allow enough clearance for full strut adjustment in all directions.
This is all just an R&D thing anyway. If it works great. If not, back to the drawing board - or just settle for what is on the market.

Dustin Mustangs

iTrader: (1)

A pivot or 'pin' connection is normally used when you don't want to transmit a bending moment. With a pin at each end the only forces that the bar will see are axial, ie tension or compression along the length of the support. Knowing that this is the case when you are making the piece allows you to make it stronger for any given weight because you have just limited the forces that it will have to resist from 3 to 1 (from axial, shear, and moment to just axial). Making this same connection ridged is kind of a joke anyways because the support is so much longer then the weld securing it and/or the piece transmitting the load to the strut tower. Because of this it likely wouldn't do much of a job of dealing with the torque produced by such a big (relative to the other two pieces) lever arm and would fail or deflect under load anyways. Really the only way to keep the struts straight up and down would be with supports at top and bottom and a cross-brace between the two, but that's unrealistic because it would have to go right through the engine.

charliemccraney

Dustin,
That is the type of info I've been looking for. Do you know of any sites that offer info on stb's? Not what they do but more on how they work from a mechanics (Physics) standpoint. Maybe even someone with real world experience with both pivoting and ridged stb's.

Dustin Mustangs

iTrader: (1)

No, sorry. That's not info I found on the web. It's from classes I took on structural engineering and the like that really can be applied to anything that is resisting a load. I really don't think you'll find anything on the net that goes into depth like this specific to stb's.

I will say that unless you went absolutely buck wild on gusseting, there is no advantage to going with a fixed (rigid) connection here. Anything less just wouldn't be able to keep things square and would likely weaken and or fail over time if asked to do so in a worst case scenario and simply not do what you'd want it to in a best case scenario.

charliemccraney

So that's how one spells rigid. I thought ridged was incorrect!

I was thinking the same thing about a rigid bar. I was just thinking about the forces applied and picturing it in my head and all I could picture was a failing brace over time. I have not had the engineering classes but that sort of stuff seems natural to me. I loved physics in high school and I especialy like reading about light, gravity, and quantum theory. I can understand those books the first time I read them.

I have noticed that the rigid bars are much less common than the clevis design during my search for info over the past few days.

89_ho_rs

i just put mine back on. its painted.

charliemccraney

Nice! That is a great looking piece! I wish I could get stuff done that quick. A freind and I share tools. We live about 7 miles apart. If I need to use something of his I have to run over to his shop and get it and vice versa. It can cause simple things to take a while.
Great job!

83 Crossfire TA

iTrader: (2)

Really, both ends of that argument don’t agree… If the connections aren’t rigid enough then putting pivots in either end won’t make any difference in the strength/given weight. But nutshell, unless you make it big, heavy and many more connections it really won’t make that big a difference if you have pivots at the ends or a solidly welded bracket.

Um, easy: solid motor mounts and use the engine block as a stressed suspension/chassis member. You’d be surprised how little you’d notice the change going to solid mounts on a lot of the already modified cars out there.

Xophertony

ok i have carefully read this post and have a question or three.

1. the three bolts holding the black thing (black on my white car anyway, red on his, but you know what i mean) on top of the tower are not for adjustment purposes? they just hold the black thing on?

2. the black thing holds the strut wich in turn has its own adjusting bolt at the very top covered by that plastic cap yeah??

3. why should i not mount a STB to the three bolts

4. will a solid(non pivot) design cause any problems over a pivot design?

Dustin Mustangs

iTrader: (1)

Maybe I didn't word that the best. It wouldn't actually be stronger, but it would have less of a load to deal with in certain situations. The primary loads for a stb are tension and compression, I think we can all agree on that. Say you are in a max effort cornering situation that has your stb in a state of compression at 90% of it's available strength (likely if you are trying to keep things as light as possible). Lets also say you have rigid connections at each end of your stb that are trying to resist a small amount of vertical scew between the two st's. This is going to induce a moment (a bending force) across the stb. Anything under the influence of a moment (being bent) will have equal and opposite portions of it's cross-section in tension and compression on either side of the neutral axis that is strictly due to it being bent. Lets say for the sake of argument that in this case this force is, big surprise, 10% of it's available strength.

SNAP!

Your stb just failed because, for one half of the member, the two compression forces are additive (90%+10%=SNIZAP). This same situation is also possible in tension given an opposite loading condition. If it was pinned, it would only have to resist the 90% load and would still be alive. Or in other words, it would have to be stronger (and likely heavier) to survive in this case if not pinned.

Now unless you have your stb designed with very little to no margin of safety this will not become an issue. I am going to make the assumption that most folks wouldn't have a clue as to the forces being delt with here, let alone the methods needed to analyze them so this argument is kinda moot. Realistically, most will skip this process, over engineer it for piece of mind and call it done. There is nothing wrong with that, I am just saying that in that case it is likely not to matter much if it is pinned or fixed.

Lo-tec

1. They adjust the front end alignment (camber and caster)
2. That is the nut that holds the strut to the mount (no adjustment)
3. Because they are too weak, and you would have difficulties doing a front end alignment, and because the bar would have to go through the carb/throttle body and brake master cylinder
4. Not really

Xophertony

thanks lo-tec. now i know...

charliemccraney

I did a google image search on strut brace and of course it is mostly ricers that come up. Man they have it easy. The majority of them have a straight shot across the engine bay. There have been some VW's, Porsche's and an old ferrari too. I am getting a lot of good visual input, however.
I am going to try a clevis design first and see how it works. I will probably build a rigid one too and ride around with it for a week or so to see if it feels any different. I have to check my hood clearance to see if the design I have in mind will even fit.

B4Ctom1

Im needing to do this around my HSR, has anyone done one or seen one for this kind of intake yet?

I need to do it as part of my "operation stop destruction" as I have seen what coil overs like mine have done to full wieght cars, and I want to lighten mine enoough where it wont get destroyed by the coil overs during occasional street driving.

charliemccraney

Well. I have been making a few measurements and have found that my slotted mount idea will not work. It just won't allow the full available adjustment range within the stock design. I could make it work for stock specs but that is not acceptable. I am now thinking about a sliding bar design but it isn't looking promising. It will probably be heavy and cost more than it is worth. I like challenges and I'm not giving up yet.
I also think that designing it so that the bar stays in one place is not necessary. There isn't much that will get in the way in a 1.5" to 2" plane. I am going to look into that as well. Then a two point design will be easy and a three point design will just require adjustable rods.

taonindo

this one works for me ... solid,simple and functional ... been on for a couple of years with no problems .... tao

B4Ctom1

seen any on a stealth ram?

icarus402001

Taonindo-- Do you have pics of your bar ends?

taonindo

this is the best i got right now but next time its off ill try to get some.....i just wielded a small tube at the end of the bar and bolted it to the lip of the fire wall......tao

fitbmxseries1

im thinking about making one but i have the tpi engine and will probably have to do some bending... i have accsess to pretty much every tool i need but a tube bender.. any one got pics of a tpi with one?

icarus402001

Tao--- how about a close up of the strut tower attachment?

taonindo

dont have a camra but ill try too...the mount is 1/4" plate mounted directly to the strut bolts...kinda of a pia to get on or off but it can be done...hope that helps ya.....tao

icarus402001

That does help. Thanks