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Discussion Starter #1
I was hoping that someone here has done a mustang 2 front end and did a
reinforcement from the frame area of the cross member back to the fire wall to reinforce the shock tower rigidity you just took out.

I am thinking of doing this 2 ways.

#1 Just weld 1 5/8" tube from roll cage left overs from frame rail to fire wall (with 6-8" plate on firewall) k-member area will be plated already.

OR...

#2 I know I am doing a 4 point, roll bar with back bars. I could do the hoop and front down bars and tie the frame to the cage like a usual 12 point.

I would like to stay away from this option.. but if someone has done modification #1 and it did not work out then I guess I have no choice.

I also seen the way Julio did it on SN65 website. Never seen it in real life, or on the internet.

This is not a track car, but will have some good power (700 or so to the wheels)

So... what do you guys think?
 

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Of all of the MII modifications done out there, have you ever heard of one having problems from removing the shock towers?
Think about it. Then call Rod & Custom Motorsports and talk to them about how strong one is with the towers removed.
Just get a good set of sub frame connectors. There is a do it yourself build posted here on VMF you can do, or mail order a set already made for $165.00
 

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I was hoping that someone here has done a mustang 2 front end and did a
reinforcement from the frame area of the cross member back to the fire wall to reinforce the shock tower rigidity you just took out.

I am thinking of doing this 2 ways.

#1 Just weld 1 5/8" tube from roll cage left overs from frame rail to fire wall (with 6-8" plate on firewall) k-member area will be plated already.

OR...

#2 I know I am doing a 4 point, roll bar with back bars. I could do the hoop and front down bars and tie the frame to the cage like a usual 12 point.

I would like to stay away from this option.. but if someone has done modification #1 and it did not work out then I guess I have no choice.

I also seen the way Julio did it on SN65 website. Never seen it in real life, or on the internet.

This is not a track car, but will have some good power (700 or so to the wheels)

So... what do you guys think?
Wow, this is the second post today where my first instinct was to laugh at the title....;)
 

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OK, I'll go ahead and say it..............I just think of the time I got to drive a GT (as in GT40). Works like a charm and the wife has no idea...lol
 

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Discussion Starter #5 (Edited)
Of all of the MII modifications done out there, have you ever heard of one having problems from removing the shock towers?
Think about it. Then call Rod & Custom Motorsports and talk to them about how strong one is with the towers removed.
Just get a good set of sub frame connectors. There is a do it yourself build posted here on VMF you can do, or mail order a set already made for $165.00
check out my car domain page for my sub frame connectors. with the 4 link and 12 inch tires.
I will not have one 7" wide tire wheel hopping down the street.

I am not doing a 289 with a cam.. I am doing a twin turbo built LS2.

I have seen framed cars twist from to much torque. They did not rely on the uni body as the ford does.
I poped the door panel skins off of my 02 camaro.
I twisted a fox body mustang bad enough I got red of it. I thought I could get away with not caging it.. that was just a mild 393 on a 150 shot.

So you see why I am a little worried?

Reason why you do not hear of other cars twisting is because they either do not have the output or they have 12 point cages that tie everything together.
 

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Take a look at the tiger cage and they way that the door bar is run. It will work w/ your 4 pt and you can tie it in along several points though the car on up to the front frame rail.

On the foxes w/ full cages we put a bar through the strut tower, c notch the tower then weld it all up w/ the bar in place and it drops down and ties in just in front of the sway bar mounts. you could mimic that.
 

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i meant it as more of an example along the lines of tying in the front of the frame does help, even going through the thinner sheet metal on the early stangs would probably destroy the tower.

as for the tiger reference extend the low slung side bars through the front of the car instead of stopping by the kick panel rather than putting a hoop in, loosing head room and smacking your head everytime you get in and exit and hacking up the dash to do it, though if you are getting enough flex from it you may have no choice but to put in the hoop and dropping bars forward to the front rails to get the leverage you may need.
 

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GM engine in a Mustang....


...Go away!

BAN HIM!!
 

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Discussion Starter #10
GM engine in a Mustang....


...Go away!

BAN HIM!!
I drive a tundra, building a ford with a chevy motor... I get around... I'm not into the whole die hard one size fits all stuff..
I take my mechanical experience and make real decisions.
I was the first one on the block to make a F1R Procharged stroker 4.6 the second Kelloggs started making the crank. it cost me 15 grand to get 900HP (with me building it)
I can get that with a stock ls2 and the turbos if i wanted. (7k max)
I could go with the good old 351 but I have been there, done that. I don't have a assembly line in my garage, I like to build different stuff. It is a hobby!

I could do a 427 SOHC, I know where I can get one for 10k, or I can buy one in a cris craft boat for about the same... Not what I want to do with this car!

All I can say is you build what you want, I will build what I want.
 

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To avoid a cage, and still have strength you'll have to get creative. I also don't like the idea of the MII front end without it trussed into the unibody. I know its done, but a lot of things are done as you know.

1. I assume we are talking a multi use vehicle with one of those uses being the drag strip.

2. I'll also go out on a limb and assume that even with a Chevy motor (tongue and cheek) that you'll be exceeding the ET that'll require a 6 point rb. If so, your running some type of door bar.

3. Why not an X brace in door to a hidden dash bar that can connect the nodes to the outriggers at or in front of the MII cross member? Now for safety alone lets face it, one continuous bar is going to be stronger, but you could go with back to back 4-6 in plates at fire wall. to tie into cage.

Can you visualize what I'm talking about? Now not near as triangulated but you could run a parallel bar above frame same a couple inches that would tie into door bar also. If you made verticle straps at intervals from 3/16 plate to OEM frame you'd essentially make an I beam.

Also reference the chassis strengthening thead in the track section I started for more creative ways of creating rigidity. As you already know, you need more than just longitudinal strength at these torque levels but also torsional rigidity. Frame connectors are NOT going to cut it if you hook up.

4. purple pill
 

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a quote from StangNet:

"I asked my wife the structural engeneer to come look at this thread. Talk about opening a can of worms. She does seismic retrofits, and I can hardly understand a word she says after I ask her a question like this, but I'll try.

Basically, you're screwed, but you've already articulated why.

You can measure defection at the core support, but the measurement is meaninless because you don't apply any torque there anyway.

You can't measure deflection under the shock towers becasue you have to cut them off to get the bar in.

I've seen the Mustang II conversions fail right behind the crossmember. It breaks the frame. My wife explained that taking the shock towers and export brace out moves the load path and the beam deflection from being shared with the cowl and concentrates them on the frame rails. The problem then becomes that the whole car rides on the framerails, and they weren't designed to take that sort of load. Which explains the failures I've seen.

If I were you, the big deflection you got when you pulled the export brace but would be my major concern. I don't know/have any ideas how you get the loadpaths back from the crossmember to the cowl now that you've removed the shocktowers, but that would be where I would focus my energy.

Hope this helps."

So I guess it does happen by someone's witness.

Here is the thread it came from and more thoughts on strengthening beyond ours here on VMF:
http://www.stangnet.com/mustang-forums/723029-torsional-rigidity-test-67-coupe.html
 

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When I get a chance to read through that thread I certainly will but I wil simply state this after reading just the 1st post. There is a variance from aftermarket manufacturers how far back their frame reinforcement plates travel on the stock rails which will certainly effect the test as performed.

-J
 
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