Ok fellahs, I’m making plans to install an Export Brace on my '70 Eliminator. I’m tired of the headers rubbing on the shock towers and making that horrible screechy-screech, and I figure the Export Brace will be my best bet for pushing the shock towers back where they belong, as well as helping to stiffen up the front end a bit.
I have a few questions / concerns before I jump in though…
I want to know in advance if I should expect something to come shooting off.
Is the shock tower cap under any sort of tension?
Could there be tension on the factory cowl brace between the shock tower and the firewall?
My plan is to use a bottle jack, piece of pipe, wood blocks and towel padding to push the shock towers apart for installing the Export Brace.
Is this feasible with a big block? I’m not sure if there are any clearance issues or not.
I understand that I might also need to jack the car up a bit here and there to get the various holes to align properly. I also read that I might need to jack / lift the engine a bit. I don’t want to crush the oil pan or destroy a motor mount, or anything like that.
What is the best way to jack up the engine?
Is my wheel alignment going to be affected much? I imagine I’ll need to get it aligned after moving shock towers, but will it shift alignment too much to allow driving it to the alignment shop?
Are there torque specs for the shock tower cap nuts and the firewall bolts?
I understand that the Export Brace sits on top of the shock tower, then the tower cap goes on top of it. And the Export Brace has to sit on top of the pinch weld at the firewall, based on the contour ridges sticking up. And then the Export Brace Mounting Bracket (optional) can go on top of the export brace, or with some modifications go underneath the pinch weld and sandwich the pinch weld.
I would try placing the car on jack stands at the frame rails by the torque boxes first. This may be all you need. Some times letting it sit on the jack stands for a day or so helps too. The last 2 I installed just dropped in to place. But 1 was a 351W and the other was a 351C 4V, If that does not work then try pushing them apart with a setup like you described.
Nothing should come shooting off. You’ll have to hold down the shock when loosening the two bolts but after that, everything should just come off without too much trouble.
A one piece shock tower brace is veering off the stock path a bit for you, isn’t it Mike?
Yes, and I’m torn on that, but I think it will be a good compromise. I’m pretty sure the shock towers have sagged quite a bit, sammiching the engine between them. So I think a shock tower brace will be a good way to put some space between the headers and towers again. And keep them straight if I’m going to be driving it around.
The original 1965-66 Mustang export cars had the angled reinforcement brace welded to the top of the cowl. Unfortunately, the Mustang/Shelby part will not fit our later cars without modification because the cowl is bent at a different angle. You can bend the bracket to 90 deg and weld it underneath the pinch weld. This brace will significantly stiffen the cowl area where the export bracket is bolted.
I have heard stories of shock towers that have sagged, etc. But (JMHO), don’t get your hopes up that yours have sagged enough to cause header rubbing (which is a good news/bad news story, right?). Headers almost without exception do a superb job at rubbing all on their own, even with the body structure in perfect alignment. A BFH applied in the right places on the headers and sometimes a little nip/cut here or there on engine mount brackets or tower reinforcements is the usual Rx for fixing such. This has been my experience without exception over many years.
This is the one upgrade that took me a bit of time to do. Mine is a 69 S code XR7 vert. I started on the passenger side, went along the fire wall and finished up on the drivers side. That one inside bolt of the 3 was the worst to line up. I did jack the car up a bit to try to help align the holes. I was doing a bit of prying too.
I really did yell out in joy as the last bolt aligned.
Thanks Don - I’ve been doing some research and got the chance to personally inspect some genuine early Shelby Mustangs and a '70 Boss 302 Eliminator and I have a few questions.
There is a brace that is welded onto the top of the firewall pinch weld, under the one-piece export brace on '65 and '66 Shelbys and there is also a smaller brace used on Boss 302s (like what is shown in your video) that looks like it is not welded and used in conjunction with the stock, two-peice firewall to shock tower braces - is this correct?
And if so, do you carry this smaller Boss 302 style brace?
The brace on the yard car looks to have been flipped around (maybe when the passenger brace was removed, and it was just stuck back in place), and it looks like that brace has a bit of a lip on the vertical section as well.
Like Jeff pointed out, no idea if it is original or not, but it does look to have a shorter vertical section than the Shelby version ~ closer to what you see on the Boss 302 pic above.
The Boss 302 one that you posted looks to me like a cut down version of the Shelby / reproduction brace maybe?
I looked through some of my Eliminator pics and found a few examples. Interestingly, it does not show up on all Boss cars - notably Dave W’s unmolested 0F91G512239, but also a few others. Seems the bracket is present on about half the Boss cars that I have pics of, and almost all have the bracket with the vertical section facing out - which matches the appearance of the WCCC yard car.