Upper control arm bolt holes

[Glenn83 19]

i know this mite be a long shot but has anyone got a measurment I could use to check the two upper control arm mounting bolt holes?? I was having a look at my car (still a bare shell) something doesn't look rite with them, it's had the shelby drop done but one side looks a tiny bit different than the other.

[prayers1 153]

What seems to be a little different?  Take some pictures and measurements and post them.

 

IIRC. the Shelby Drop new holes will be tilted.  Check out, dazecars.com   Read and check out his pictures and compare.  You might want to drop him a line.

[Brian Conway 264]

Ditto.

[Ridge Runner 1,114]

for a 69 ,The holes should be straight in line and one inch below the top holes .the 65-66 holes are 1 inch down and 1/8 inch back .

[det0326 179]

I know that what you guys are saying is correct   because I am considering doing this to my 69 as well. Little bit off the O/P question but seems a good place to ask a question.  We all have read threads about not enough caster when doing the  Borgenson power steering upgrade which I am considering also. With that said a center line through the holes just like Brians posted pic is not parallel with the frame rails  It would be some degrees difference so if you drop the holes down 1 inch at the same angle as the original holes (which is correct I not disputing that) wouldn't that actually move the top of the spindle forward decreasing positive caster and make it more difficult to add more positive caster for the Borgeson power steering unit which helps with return to center. Why could you not actually move the holes rearward a little to help with positive caster. 

 

Thanks Dave

[Ridge Runner 1,114]

Not sure why adding a Borgeson steering would change the caster because the Control arm would still be in the same location.

The drop plants the tire different in a turn ,instead of the top of the tire leaning out it leans in and the bottom is planted out ward giving more tire surface to the road .If you ever get the chance to drive a car with the control arms in the stock location then get into a car that has the drop done you will see the difference ,especially in a turn .caster is easily adjustable in 67-70 because the radius rod is adjustable so the lower control arm can be moved forward or back ward .

[shaun071 62]

I can't remember where I saw it but have seen where the upper holes were moved rearward as well to help with getting enough caster adjustment. Modern tires have different caster requirements to the crossply tires these cars were designed for.

[Glenn83 19]

Thanks for the replys, appreciate it. Here is a pic of the drivers side, my main concern is the guy that done the drop didn't use a template he just measured it he also said he added a bit more offset whatever that means, the guys is quite a smart fella, he has done a lot of stuff with race cars over the years. Maybe I am over thinking too much.

[Ridge Runner 1,114]

Really hard to tell anything with out the other set of holes for reference .You can actually go lower than 1 inch but you will have to run a negative wedge kit .

I have always measured when i lowered control arms ,you just have to make sure your measurements are correct ,and center punch your mark so the bit doesn't walk .I always start with a 1/8 inch bit first as a pilot and to keep it from walking off my mark .It helps to have a small square to connect the centers also .

[det0326 179]

Not sure why adding a Borgeson steering would change the caster because the Control arm would still be in the same location.

The drop plants the tire different in a turn ,instead of the top of the tire leaning out it leans in and the bottom is planted out ward giving more tire surface to the road .If you ever get the chance to drive a car with the control arms in the stock location then get into a car that has the drop done you will see the difference ,especially in a turn .caster is easily adjustable in 67-70 because the radius rod is adjustable so the lower control arm can be moved forward or back ward .

No I'm not saying the Borgeson will have anything to do with caster. I have read and some others that did the Borgeson swap experienced not enough positive caster among other things that caused the steering not to return to center. Some have said too that trying to pull the LCA forward enough to increase caster put a bind on the LCA . I don't know this to be true but its what other people doing the swap has experienced.  Yes I understand the drop and what it does, I was just wondering why you could not move the holes rearward a little and 1" down at the same time. gaining a little caster so as not to have to pull the LCA so for forward to gain caster . I guess every car is a little different but I have also read that trying to get enough caster by tighten the radius rod pulling the LCA forward caused the tire to be too close to the front part of the fender lip. I'm just trying to find out all my options and do's and don'ts before I get started on this front end upgrade.

 

Dave

[Glenn83 19]

Really hard to tell anything with out the other set of holes for reference .You can actually go lower than 1 inch but you will have to run a negative wedge kit .

I have always measured when i lowered control arms ,you just have to make sure your measurements are correct ,and center punch your mark so the bit doesn't walk .I always start with a 1/8 inch bit first as a pilot and to keep it from walking off my mark .It helps to have a small square to connect the centers also .

I"m thinking I should just run the negative wedge kit just to be safe, shame there so expensive. Thanks for the reply

[Glenn83 19]

What seems to be a little different?  Take some pictures and measurements and post them.

 

IIRC. the Shelby Drop new holes will be tilted.  Check out, dazecars.com   Read and check out his pictures and compare.  You might want to drop him a line.

That's a really good webpage, I sent the guy an email.

[det0326 179]

I can't remember where I saw it but have seen where the upper holes were moved rearward as well to help with getting enough caster adjustment. Modern tires have different caster requirements to the crossply tires these cars were designed for.

Yes shaun you might be thinking about the 65 and 66 mustangs template it actually has the holes rearward a little that's why I was wondering why you could not do the same to the 69.

 

Thanks for the replies guys

[det0326 179]

Sorry glenn for the high jack I was just getting started on this upgrade myself and thought this was a good place to get some info without starting another thread of basically the same topic.

[Ridge Runner 1,114]

I see no real reason you could not drill the holes back like the 65-66 ,as i said the radius rod is adjustable .It just depends on if your radius rod would adjust far enough back .I am running an Aeroform suspension kit and it is adjustable in any direction you can think of .

[Glenn83 19]

Sorry glenn for the high jack I was just getting started on this upgrade myself and thought this was a good place to get some info without starting another thread of basically the same topic.

That's cool man all the more info the better, I'm gonna throw a borgeson box in also so it's all relevant

[Glenn83 19]

I see no real reason you could not drill the holes back like the 65-66 ,as i said the radius rod is adjustable .It just depends on if your radius rod would adjust far enough back .I am running an Aeroform suspension kit and it is adjustable in any direction you can think of .

This might sound like over kill but I've gotta replace the rear fender aprons so while I'm at it I might do the shock towers also and start again , considering the negative wedge kit is about 300 bucks the 2 new shock towers is about the same price.

[Ridge Runner 1,114]

You could always fill in the holes and redrill them if the towers are in good shape

[Glenn83 19]

Well I just buffed off the primer and I think I can see where the old holes were filled, I'll buy a template and see how they look

[Mike65 476]

Well I just buffed off the primer and I think I can see where the old holes were filled, I'll buy a template and see how they look

Glenn, are you getting the template for the 69, if so I have one sitting on my workbench you could borrow. Just pay the shipping both ways & you could use it. Let me know.

Mike.

[Glenn83 19]

Thanks for the offer Mike, but I live In Australia, but it's good of you to offer

[Mike65 476]

Thanks for the offer Mike, but I live In Australia, but it's good of you to offer

Ooops, didn't notice that.