Vintage Mustang Forums banner

21 - 40 of 48 Posts

·
Registered
Joined
·
391 Posts
Discussion Starter #22
Hello everyone,

Made some decent progress this past weekend.

I'm starting on the firewall area. So, I wanted to remove my seats (mainly to wrap them in plastic and protect them) and then I removed the front portion of the carpet to keep from setting it on fire lol.
761361


761362


761363


761364
 

·
Registered
Joined
·
391 Posts
Discussion Starter #23
Then I got started in the engine bay. I got started on the passenger side and tried to work my way around to the drivers side.

Here is the top of the passenger side apron. Had some rot mixed in with the spot weld holes. So. I decided to cut it out. Trying to smooth out to top rails any way.
761366


761367


761368


The lower part of the passenger apron had a small rot spot. Time to cut out the bad metal...….
761369


761370


761371


There were two bad spots of the lower part of the firewall on the passenger side (you can see the plate my brother welded on the inside of the car. Not the right way to do it, but it kept water out). I got it cut out, but it has been upwards of 108 degrees outside. So, I didn't get a chance to patch this area yet. Sure is hard to weld in 108 degree heat with no A/C in the garage LOL...….
761372


Here are the bad pieces I cut out. Here you can see the two bad pieces I took out of the lower firewall area.
761373
 

·
Registered
Joined
·
391 Posts
Discussion Starter #24
Then I got started on the rear portion of the frame rails.

Picture of passenger side frame rail with factory holes.
761374


I used my plasma cutter to cut out some plugs since the hole was too big to just try and weld it up.
761375


All welded up and grinded out.
761376


Drivers side finished up (Those dark spots are not holes, but spot welds. I'll use some body filler to get those covered up).
761377


There were some built in bolts in the drivers side frame rail. Don't need them so out they come.
761378


761379


761380


My friend told me about the use of Argon gas during MIG welding. So, I went and got a tank of Argon gas and hooked it up to my welder. MAN!!!! Things are so much cleaner now. Wish I would have started out welding like this. Would have made the project much easier. Oh well, live and learn.....
761381


761382
 

·
Registered
Joined
·
391 Posts
Discussion Starter #25
Then it was time to start working on the firewall. Originally there are support braces that went from the shock towers to the firewall area. Well, shock towers are gone, so I wanted to shave that lip with the bolt holes off. I think it looks so much cleaner now. I still need to do more cutting/clean up in the corners. However, I wanted to get things welded up and grinded smooth. Should look pretty cool once the body work is completed.

Here is the lip with the holes I was talking about. FUGLY...…..
761383


Here is my initial cut. There are two spots you can see I got a little over zealous with the cutting wheel. Oh well, can patch those areas up later...…...
761384


Time to address the lip on the drivers side.
761385


Got some spot welds in place just to keep everything in place.
761386


Side view to show how much cleaner it looks. As mentioned, I still need to work on the corners.
761387


More spot welding...…
761388


Here is how it looks once the spot welds are ground smooth. Should look killer once body work is completed.
761390


Ended up getting the patches welded in, but did not have time to grind smooth. It was hitting 106 outside again. Damn, it's hot LOL......
761391


Second patch...…..
761392
 

·
Registered
Joined
·
391 Posts
Discussion Starter #26 (Edited)
Then I decided to make one more patch panel before I called it a day.

The two circles with the rectangle underneath are where my engine harness goes through the firewall. I'm going to reroute those wire in order to give my firewall a cleaner look. So, out with the cutting wheel...….
761393


761394


Patch panel made. I'm really happy with how my ability to make these patches to line up great is getting. Makes welding so much easier...….
761395


761396


And this is where I ended. Didn't get a chance to get all my welds grinded smooth. It was just too damn hot LOL. As you can see I didn't even get a chance to get those two patches for the lower part of the passenger side firewall completed either...……
761397


761398
 

·
Registered
Joined
·
391 Posts
Discussion Starter #28
The support will come from the new cross member which is significantly thicker than the original cross bar used by Ford. Also, the front of the frame rails are supported by a triangular jack pad which is also made out of significantly thicker metal than the thin pieces of metal Ford used for the strut rod bars.

Also, I have installed subframe connectors to stiffen the chassis. Lastly, I'm contemplating adding Mustangs to Fear frame stiffeners to increase the strength and tie it all together.

761403
 

·
Registered
Joined
·
1,613 Posts
Did you wire-wheel the entire bay down? How long did that take you out of curiosity?
 

·
Registered
Joined
·
391 Posts
Discussion Starter #30
Did you wire-wheel the entire bay down? How long did that take you out of curiosity?
I did not use a wire wheel. I used an abrasive wheel to get the thick stuff off (i.e. undercoating) and then I used a 26 grit sanding wheel to get the majority of the paint off the engine bay. Both where used on my air sander.

Also, I cut the original radiator support, shock towers and front aprons off. So, I only needed to sand the rear aprons, firewall and frame rails. For what you see sanded in the pictures (i.e. down to metal) took me one weekend.

This is the abrasive wheel I use to remove thick and stubborn residue such as undercoating.
761404
 

·
Registered
Joined
·
1,613 Posts
Just about as miserable as my sandblasting efforts then(Its not very fast for me, not sure if its solely due to the grit of the media I am using or whether I am blasting at the wrong psi or what, but its taking forever)
 

·
Registered
Joined
·
391 Posts
Discussion Starter #32
Just about as miserable as my sandblasting efforts then(Its not very fast for me, not sure if its solely due to the grit of the media I am using or whether I am blasting at the wrong psi or what, but its taking forever)
I hear you. I'm dreading blocking and sanding the engine bay once I lay down the body filler. Right now everything I'm doing has been with the use of a tool of some kind. Blocking and sanding will be all manual labor. Not looking forward to that at all...………..:(
 

·
Registered
Joined
·
3,379 Posts
The support will come from the new cross member which is significantly thicker than the original cross bar used by Ford. Also, the front of the frame rails are supported by a triangular jack pad which is also made out of significantly thicker metal than the thin pieces of metal Ford used for the strut rod bars.

Also, I have installed subframe connectors to stiffen the chassis. Lastly, I'm contemplating adding Mustangs to Fear frame stiffeners to increase the strength and tie it all together.

View attachment 761403
Neither the crossmember nor the front strut rod replacement structure will address the weakness created. Without the factory braces or export brace there is a pivot point at the firewall. The MTF braces sort-of addresses the issue, but I don't like how they put the load into the middle of a flat panel, it should go up higher, and outwards, to the corner of the cowl and the cowl side panel.
 

·
Registered
Joined
·
391 Posts
Discussion Starter #34
Neither the crossmember nor the front strut rod replacement structure will address the weakness created. Without the factory braces or export brace there is a pivot point at the firewall. The MTF braces sort-of addresses the issue, but I don't like how they put the load into the middle of a flat panel, it should go up higher, and outwards, to the corner of the cowl and the cowl side panel.
Thank you for your opinion and point of view. I do mean that sincerely. I appreciate your feedback and have read other posts on VMF of people with the same point of view. However, here are my counter points:

1. Why do companies such as Mustang's to Fear, Heidts, TCI and Detroit Speed make these kits if they are prone to fail or cause weak points? Not to mention this is based off of a Ford Mustang II design (A proven design).

2. You mention a weakness has been created and now there is a pivot point at the firewall. Well, when you look at the original design the frame rail itself is welded to the firewall and the rear aprons are welded to the firewall and the cowl brace is bolted to the shock towers. The "only" thing missing in the new set up is the cowl brace, which is bolted and can be removed by the owner, not welded in place by the factory. Also, the metal used in the firewall and aprons is VERY thin. Not a type of metal that would be used for structural support and this is how it came from Ford.

3. The shock towers sit on top of the frame rail. The new shock mounts also sit on top of the frame rails and the new cross member is welded to the frame rails connecting the 2 frame rails together by a significant piece of metal. The original design only has a small cross bar that is bolted to the frame rails and my car was missing this cross bar for years when I had the stock 289 in it.

4. Even Chevy used a similar design in the 60's with the Camaro. They used a front clip that is bolted to the car and not even welded in place. Then the other parts are bolted to it and there is no shock towers, no export brace and no cowl brace in their design

761419
.

I understand your point of view, but I don't think the installation of the Mustang II suspension causes a weak point that will fail or cause a pivot point at the firewall. I have never seen or read a post or web page where this has happened to someone who installed one of these suspension kits.

Again, I appreciate your comment/post. I'm no expert, but have done extensive research before starting this project. As mentioned, I built this car originally in 2010 and have been looking into this current build/set up for years.
 

·
Registered
Joined
·
1,613 Posts
A MII crossmember actually adds torsional stiffness over the factory crossmember....but torsional stiffness isn't what stephen_wilson is talking about...as for how a MII type design works in other cars is rather irrelevant unless you have metal gauges to compare and shape strength comparison data. I agree with him that the MTF design leaves a lot to be desired....I still have my shock towers...but this is the bracing I made(based off of some from Latoracing):


If I were using a MII-type crossmember this would have been modified by adding more tubing tying to the frame rail in front of the MII UCA(though it would tie to the top and NOT the side...the fender aprons could be notched around it). You are far better off designing your own than using theirs(probably cheaper too)
 

·
Registered
Joined
·
3,379 Posts
Thank you for your opinion and point of view. I do mean that sincerely. I appreciate your feedback and have read other posts on VMF of people with the same point of view. However, here are my counter points:

1. Why do companies such as Mustang's to Fear, Heidts, TCI and Detroit Speed make these kits if they are prone to fail or cause weak points? Not to mention this is based off of a Ford Mustang II design (A proven design).

2. You mention a weakness has been created and now there is a pivot point at the firewall. Well, when you look at the original design the frame rail itself is welded to the firewall and the rear aprons are welded to the firewall and the cowl brace is bolted to the shock towers. The "only" thing missing in the new set up is the cowl brace, which is bolted and can be removed by the owner, not welded in place by the factory. Also, the metal used in the firewall and aprons is VERY thin. Not a type of metal that would be used for structural support and this is how it came from Ford.

3. The shock towers sit on top of the frame rail. The new shock mounts also sit on top of the frame rails and the new cross member is welded to the frame rails connecting the 2 frame rails together by a significant piece of metal. The original design only has a small cross bar that is bolted to the frame rails and my car was missing this cross bar for years when I had the stock 289 in it.

4. Even Chevy used a similar design in the 60's with the Camaro. They used a front clip that is bolted to the car and not even welded in place. Then the other parts are bolted to it and there is no shock towers, no export brace and no cowl brace in their design

View attachment 761419 .

I understand your point of view, but I don't think the installation of the Mustang II suspension causes a weak point that will fail or cause a pivot point at the firewall. I have never seen or read a post or web page where this has happened to someone who installed one of these suspension kits.

Again, I appreciate your comment/post. I'm no expert, but have done extensive research before starting this project. As mentioned, I built this car originally in 2010 and have been looking into this current build/set up for years.
Let me see if I can clarify a bit.
1) I can't answer for the Mfg. , but generally the MII kits are a convenient package to allow for more engine room, and an "off-the-shelf" front steer Rack & pinion.
2) If you've done extensive research, one of the first things you'll hear mentioned is how flexy vintage Mustangs are. The so-called frame rail (floor support) is attached to the fairly weak floor pan, which is why torque boxes were added after the 1st generation. The only thing preventing flexing at the torque box "hinge" I mention is the fender aprons and factory cowl supports. That's barely sufficient, which is why the stronger "export brace" is such a common modification. You're right that these panels are thin, but being a uni-body car, it's strength/stiffness is derived from the design and how the loads are transferred. Now you only have small sheet metal "angle" pieces connecting the cowl to the aprons, and the aprons are weakened by the shock tower removal. I'm not saying you'll have a structure failure, I'm saying the chassis bending and twisting stiffness will be reduced. I don't know if you care about cornering performance, but one of the most important design factors is to have a stiff chassis. maybe in drag racing also, but I don't know much about that.
3) Again, strengthening the crossmember & shock mounts does nothing to transfer load to the cowl and main body.
4) You can see that the Chevy clips are of much stronger material than the Mustang, and the main body is designed to handle the point load where they bolt on.
 

·
Registered
Joined
·
391 Posts
Discussion Starter #37
Let me see if I can clarify a bit.
1) I can't answer for the Mfg. , but generally the MII kits are a convenient package to allow for more engine room, and an "off-the-shelf" front steer Rack & pinion.
2) If you've done extensive research, one of the first things you'll hear mentioned is how flexy vintage Mustangs are. The so-called frame rail (floor support) is attached to the fairly weak floor pan, which is why torque boxes were added after the 1st generation. The only thing preventing flexing at the torque box "hinge" I mention is the fender aprons and factory cowl supports. That's barely sufficient, which is why the stronger "export brace" is such a common modification. You're right that these panels are thin, but being a uni-body car, it's strength/stiffness is derived from the design and how the loads are transferred. Now you only have small sheet metal "angle" pieces connecting the cowl to the aprons, and the aprons are weakened by the shock tower removal. I'm not saying you'll have a structure failure, I'm saying the chassis bending and twisting stiffness will be reduced. I don't know if you care about cornering performance, but one of the most important design factors is to have a stiff chassis. maybe in drag racing also, but I don't know much about that.
3) Again, strengthening the crossmember & shock mounts does nothing to transfer load to the cowl and main body.
4) You can see that the Chevy clips are of much stronger material than the Mustang, and the main body is designed to handle the point load where they bolt on.
Again you make valid points and I see what you're saying. My only answer is I'm not building this car to be a road course car or a drag car. It will mainly be a street cruiser that sees cars shows. So, my car should not see much chassis flex.

Not sure if you seen my original post, but I used to drag race this car when it had the original factory setup in place. However, I blew the motor. It gets too expensive to be building things, breaking them and then rebuilding them again. Therefore, this time around I'm more worried about the car looking good and driving well rather than worrying about all out performance. I've always liked the 427 and want to have one and place some badging on the car to indicate what's under the hood.

This might seem trivial to some, but again I'm building a weekend cruiser that will not see track time. Of course I want to build it right, so your feedback is welcomed and I'll look into adding torque boxes and anything that may help reduce chassis flex.

Thank you Stephen...….
 

·
Registered
Joined
·
391 Posts
Discussion Starter #38
Hello @stephen_wilson . I was thinking about your comments and got to thinking about all the guys adding Coyote motors to their cars.

I found this thread:

This guy put a Coyote motor in his 1966 coupe. It dynode 500HP. Then I seen he also used a MTF MII front suspension set up. He is apparently under the same impression I am when it comes to the frame rails according to this post.
761489


I am "NOT" tryin to debunk your theory. I'm just trying to figure out how it works for others. Especially those who have done a Coyote swap that requires the removal of the shock towers due to the size of the motor and to figure out how they have addressed the issues you have brought to light.

Bad thing is for some reason I cannot see the pictures he posted in his thread. So, I'm not sure what he has done, if anything, to stiffen up the car...….. Same thing for @wicked93gs who posted a picture above. However, all I see is a small black box with an "X" in it. I even tried to use Chrome and still no pictures. Not sure what the problem is.
 

·
Registered
Joined
·
391 Posts
Discussion Starter #39
Hello Everyone,

Well, this weekend was a birthday weekend in my family. So, I only had one day to work on the car. Not much done, but progress was made…..

This is under the dash. The black is the back of the firewall and the brown is under the cowl. I'm not running A/C or a heater. So, I'm using this area to mount my electronics. My MSD Box, Starter solenoid, Relays and other electrical items will go here. So, I'm welding some square tube in order to mount a plate so I can screw my items to the plate and not put a bunch of holes in my original sheet metal.
761989


Cleaning up the metal to prepare for welding.
761990


Got my square tubing welded in. I need to get the plate measured up. Then I can lay out my electronics and then screw them in place.
761991


My buddy was able to make it over. He's a WAY better welder than I am. So, he came over, got my welder set up and went to town on the main items that my suspension will be mounted too. Man, his welds look sweet.....
761992


761993


761994


Then I was able to clean up my spot welds on the firewall.
761995


761996


I was able to spot weld the plates in place on the bottom part of the passenger side firewall.
761997


Lastly, I ordered my torque boxes and Mustangs to Fear frame stiffeners. So, I started to get the drivers side outer firewall area cleaned up and remove all the under coating. Damn, is it a pain in the _......
761998
 

·
Registered
Joined
·
238 Posts
Again you make valid points and I see what you're saying. My only answer is I'm not building this car to be a road course car or a drag car. It will mainly be a street cruiser that sees cars shows. So, my car should not see much chassis flex.

Not sure if you seen my original post, but I used to drag race this car when it had the original factory setup in place. However, I blew the motor. It gets too expensive to be building things, breaking them and then rebuilding them again. Therefore, this time around I'm more worried about the car looking good and driving well rather than worrying about all out performance. I've always liked the 427 and want to have one and place some badging on the car to indicate what's under the hood.

This might seem trivial to some, but again I'm building a weekend cruiser that will not see track time. Of course I want to build it right, so your feedback is welcomed and I'll look into adding torque boxes and anything that may help reduce chassis flex.

Thank you Stephen...….
@Black Gold 380R . You'll get varying view points on the Mustang II suspension. I have installed mustang II type suspension on various mustangs. What I will say is based on experience from building my brother's 66 mustang using the mustang II suspension. His goals are almost exactly like yours, but he daily drives his. A few things I'd like to say before I give my $.02 on the debate.
  • I'd like to think all the suspension companies did their stress analysis on the suspension kits
  • All companies out there have their following/followers.
  • Some of the said companies have great success using their product in the racing world, but sometimes not all racing stuff translates to the real world
With that said here is my $.02 or just a FYI.
  • As mentioned earlier, the mustang II does add torsional stiffness, but it subtracts bending stiffness. The shock towers, export brace, monte carlo bars, etc act as a truss for the sheet metal frames. Even though some of these connections are bolted together, they do help provide bending stiffness. What you will also notice, is that none of them are flat. They have a height to them which increases bending stiffness. But making them one piece increases the stifness even more. Your example of the front subframe used on gen 1 camaros and later is not really accurate. The front suspension that more closely mimics the mustang front suspension is the 62-67 novas which will bring me to my next bullet. Ironically Hotchkiss makes down bars now that tie the upper control arms to the firewall for the Chevy crowd.
  • Definitely install the down bars from the firewall to the frame rails. This part is based from personal experience. The fender aprons were not designed to take the suspension load and/or vehicle weight cycling up and down. You will eventually start to see cracking/separation in the cowl area where the fender apron is attached as well as where the front and rear fender aprons are welded together. The time it took for the cracks to appear on my brother's car took about 7-10 years of daily driving and they progressively got worse. As a side note, many aftermarket manufactures of the Nova suspension incorporate the down bars in their kits to try and replace the strength loss from removing the shock towers.
  • I do have analysis to back this up. This is of a simply supported beam with the fixed point mimicking the firewall as an infinitely strong fix point. Similar to the mustang/nova. The first 2 pictures are the stress and deflection without the down bars. The last 2 are with. Notice how much stress and deflection decreased just by adding the down bars. Just remember, this is overly simplified. Numbers will change when you add fender aprons and cross members.
    762011
    762012
    762013
    762014
  • Even if all the companies have done their due diligence, real world is all that counts. What I haven't seen from any is daily driving experience for an extended period of time which I think is the key. Even with the stress analysis I did, there is no guarantee the down bars will eliminate cracking, or if my brother's particular instance was even a one off, but I do have a better understanding of how it could happen.
Conclusion - In my opinion add as much back that you can. Down bars, torque boxes, etc. I'd tie the down bars across to mimic a monte carlo bar and even tie that back into the firewall to mimic the export brace. Just FYI, I too have eliminated my shock towers on my coyote swapped 67 cougar, but I have added the aforementioned parts. I wanted a stiff chassis because I wanted the car to handle. If I had to do it all over again, I'd notch my shock towers and mimic a boss 429 setup to fit the coyote in. Everything is my opinion based on my personal experience and just wanted to give you my insight. You're doing a great job on the car.
 
21 - 40 of 48 Posts
Top