Strut tower brace for cobra jet intake and chassis flex reduction

[twistedneck]

Seeking structural braces for the Boss that will clear the cobra jet intake manifold.

I took my Boss brace off after fitting the cj intake and honestly I don't notice it missing in terms of flex around corners.

What are your thoughts on the value add of the strut tower brace anyway? I've seen deflection studies that show less than 4mm of movement on a track in a similar vehicle (Camaro) w/o the brace. I've also heard the increased negative camber from the slight flex actually helps turn in.

Is there a three point brace available for our cars? Looking to stiffen up the chassis, what are the first big items to do that? Hoping to get a custom 5pt cage welded in this winter and I need ideas as to what are the critical areas to stiffen - i.e. are door bars needed to make the car stiffer?

Thank you

 

[steveespo]

I don't know what the race teams do other than the cage and seam welded bodies but they run no tower brace. You can also get Prothane or Steeda urethane motor mounts and lower the engine 1/2". That's what I have and the brace fits fine.

Steve

 

[twistedneck]

I don't know what the race teams do other than the cage and seam welded bodies but they run no tower brace. You can also get Prothane or Steeda urethane motor mounts and lower the engine 1/2". That's what I have and the brace fits fine.

Steve

Thanks Steve, I have the steeda motor mounts.. When we tried to lower the engine the kooks headers started making contact w other components.

You car looks good. Obviously you have the brace and it must help.

 

[VoodooBoss]

The chassis is pretty stiff already and I'm not sure what you'll gain from stiffening it up. Member Roadhouse has posted photos of him raising the front inside wheel during turns and that won't happen with a chassis that flexes. I think you're fine without the STB but if I ever added a CJ intake I'd use spacers to raise it enough to clear the intake. BTW do you have coilovers on your car?

 

[twistedneck]

The chassis is pretty stiff already and I'm not sure what you'll gain from stiffening it up. Member Roadhouse has posted photos of him raising the front inside wheel during turns and that won't happen with a chassis that flexes. I think you're fine without the STB but if I ever added a CJ intake I'd use spacers to raise it enough to clear the intake. BTW do you have coilovers on your car?

That is good to hear i wont worry so much about it at least for now.

I'm getting coilovers from Alex at http://www.tandashocks.biz very shortly this November after the 2014 Michigan driving season is fully done. Main reasons is he sells an affordable inverted strut and his shop in Northville is only 15min away. I did look close at Vorschlag and Cortex but i'm staying local. Do you think that will compromise the chassis stiffness?

I was told that our cars are 10,000 Nm/deg. and thats a good number although many vehicles eclipse that now like BMW and newer German models. Supercars like LFA are in the 30-40k range and Agera R is 60,000 Nm/deg! Adding a cage in the right way like Watson does for the Boss 302R/S takes our cars over 20,000 Nm/deg.

 

[ArizonaBOSS]

FWIW I've removed the STB from my race car. Probably not going to make too much difference with the roll cage installed. Plus the STB weighs 7.8lbs!

I'm curious if the STBs do anything in an S197 application anyways, other than look racy.

 

[Voltwings]

I've thought about this more than once, and am not really finding many of the current designs useful, save for maybe the BMR brace:
http://www.bmrsuspension.com/?page=products&productid=194&superpro=0
Because it angles back towards the firewall.

**Now, bear with me on this part, i am going to try to explain this as best i can via text.

In my mind, a bar that just goes from strut tower to strut tower isnt doing much, because the vehicle does not Yaw perfectly horizontal, like say a boat does. Imagine this is your car with the 4 corners H. When you turn, its not like the vehicle perfectly pitches to the side, but instead more "pivots" off the firewall.
In my mind, you should view the car more like this (the tips of the V being the front tires, with the I being the firewall) I<, with loads pivoting off the firewall as said above, because i feel that is a more accurate representation of how a car goes around a corner; Think Torsional forces. It doesnt perfectly list from side to side, it pivots, so anything that doesn't tie back to the firewall isnt doing much (notice i didnt say "isnt doing anything") for the sake of that pivoting i feel.

However i am an "engineer" by hobby, not by trade, so i could be WAY off in that assumption.

 

[Roadhouse]

I've removed mine from the car. I didn't notice any difference with/without it.

 

[blacksheep-1]

We don't run them but we have cages and fully welded seams.

 

[twistedneck]

I've thought about this more than once, and am not really finding many of the current designs useful, save for maybe the BMR brace:
http://www.bmrsuspension.com/?page=products&productid=194&superpro=0
Because it angles back towards the firewall.

**Now, bear with me on this part, i am going to try to explain this as best i can via text.

In my mind, a bar that just goes from strut tower to strut tower isnt doing much, because the vehicle does not Yaw perfectly horizontal, like say a boat does. Imagine this is your car with the 4 corners H. When you turn, its not like the vehicle perfectly pitches to the side, but instead more "pivots" off the firewall.
In my mind, you should view the car more like this (the tips of the V being the front tires, with the I being the firewall) I<, with loads pivoting off the firewall as said above, because i feel that is a more accurate representation of how a car goes around a corner; Think Torsional forces. It doesnt perfectly list from side to side, it pivots, so anything that doesn't tie back to the firewall isnt doing much (notice i didnt say "isnt doing anything") for the sake of that pivoting i feel.

However i am an "engineer" by hobby, not by trade, so i could be WAY off in that assumption.

Engineer just means you got a degree.. it does not mean you know anything and it seems your logic is excellent I agree. on S550 they had to add a massive huge 6mm thick plate type strut tower brace that goes from the struts, back to the firewall fully welded and integrated for a least a 12" then goes on an angle forward to the opposite strut.. now that is a strut brace. its also about 20lbs.