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Discussion Starter #1
Have my engine pulled for the winter and looking for better handling.. Have installed some Global west UCA's and looking to take advantage of an empty engine bay.. I have been thinking about longer LCA's in serach of better geomentry. I understand the later LCA's are about 2 inches longer.. I was thinking about extending the LCA mount inward and possibly converting to a heim end link for some camber adjustability.. Has any one done this? Pictures and advice would be appreciated. thanks
 

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Discussion Starter #2
While doing research on this idea, I reached out to Shaun with Street or Track and he gave me his thoughts. One thing that I had not concitered was by moving the LCA's pick up point inward almost 2 inches I would be introducing bump steer into the equation.. So, I think this is a no go.. Thanks everyone..
 

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Wouldn't having an even longer LCA in relation to the upper also result in an increase in camber gain? Just curious... Trying to understand what the benifit of a longer arm would have been? Better leverage for a revised spring rate?
 

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Discussion Starter #5
You got it, better camber curve was the goal, but the relationship of the inner tie rod ends needs to be close to the attachment point of the LCA , if not then bump steer will happen.
 

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Hmmmmm, and there is no way for you to space the tie rods down? For instance my bumpsteer kit like most uses spacers so that the tie rod mounts lower on the spindle. Per Seans recommendation I set it as low as I could get it and tested for toe changes throughout my entire range of motion. Just as he told me, the lower I got the tie rod the better things got as far as bump steer is concerned.

Just seems like a cool idea, so I am curious if there is a way to make up for the bump steer effect without anything too crazy.
 

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Discussion Starter #7
I think a custom center link and tie rods could make it work.. IMO way too much work/money for possibly nothing.. A custom rack might make it possible.. I think after 50 years if it were a good idea there would probably be more info on it.. Was fun to think about though.. Glad I came to my senses before I got my welder out!
 

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Hmmmmm, and there is no way for you to space the tie rods down? For instance my bumpsteer kit like most uses spacers so that the tie rod mounts lower on the spindle. Per Seans recommendation I set it as low as I could get it and tested for toe changes throughout my entire range of motion. Just as he told me, the lower I got the tie rod the better things got as far as bump steer is concerned.

Just seems like a cool idea, so I am curious if there is a way to make up for the bump steer effect without anything too crazy.
It's not so much the height of the outer tie rod pivot, more the inner tie rod pivots relationship to the LCA inner pivot/length. If the pivots don't line up then they swing on different arc's and you'll get even more bumpsteer than stock.
 

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It would only make sense if you went for the whole package: shock towers, control arms and steering linkage.

It would give a larger engine bay, better suspension geometry and a wider track. The better change in suspension geometry is probably more an optimization/refinement than a night and day difference and probably doesn't justify the cost. The wider track probably means that the wheels no longer fit, which would require wheels with more backspacing and consequently, you loose the benefit of the wider track (although the reduced scrub radius may be an advantage).

It's something you might consider if you're changing shock towers and upgrade/rebuild the whole suspension anyway. Or if you want an FE big block in your '65-66 :)
 

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The idea of being able to use the 67 control arm has merit from a parts installation perspective (disregarding suspension actuation, functional design, and theory which I will leave to the experts.) The 65/66 UCA are the same length as the 67/68 stuff. The issue is that the 65/66 towers are 3-4" (or so) closer together than the 67/68. The swapped in longer 67/68 LCA would need to accounted for by mounting it even more inboard than what the factory 67/68 LCA frame mounts were designed for.

As far as steering parts, the 67/68 stuff would need to be swapped in to see the added benefits. No big deal as its a bolt in if you use the correct 67' pitman arm for the 1" shaft. Might need to experiment with tie rod ends though to get the correct lengths. I would also want to have adjustable strut rods to correct caster, but those are also available for a 65/66.

Not sure how the 65/66 spindles would come into play or if the swap to 67+ spindles would be a good or a bad thing in this odd ball combination (they have a relocated tie rod arm.)

It would only make sense if you went for the whole package: shock towers, control arms and steering linkage.

It would give a larger engine bay, better suspension geometry and a wider track. The better change in suspension geometry is probably more an optimization/refinement than a night and day difference and probably doesn't justify the cost. The wider track probably means that the wheels no longer fit, which would require wheels with more backspacing and consequently, you loose the benefit of the wider track (although the reduced scrub radius may be an advantage).
Your info is correct but I would like to add a little clarification. The major limitation of doing the whole package is that the 65/66 body width is narrower than the 67+. To make my "whole package" shock tower/suspension swap work I used the early narrow 65' style steel wheels (66/67 are "similar.") IIRC, they are 5" wide. The wider track is definitely still there but you can't install a wide tire due to to the wheel wells which have a smaller opening than the 67+. I use a 195R/75x14 front tire and the increased track width is still very evident when you look at my car. That tire works well for my drag car needs but wouldn't be worth a crap on a road coarse. Since my front fender wheel well lips are still intact, one might be able to use a slightly wider rim and a different aspect tire to get a little more rubber in there.

Wish I had a photo from the front, but all I have is a side view. I run 5* caster for drag usage so that explains why the wheel is pulled forward in the opening:



The front of the car also sits higher than what one would typically want. The new springs never did settle and that is being taken care of this winter.

From: http://forums.vintage-mustang.com/mod-custom-forum/827730-grafting-67-68-shock-towers-65-66-mustang.html

PS, the signature photo is with the 65 suspension so its not a valid reference for the 67/68 conversion.
 

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I know the Fox body Mustang guys would use T bird lower control arms that were longer to improve camber.

I'm by no means an expert on suspensions but I am curious and have gotten quite involved on my 66's. I'm running Shaun's parts. My take on bumpsteer is you want the lower control arm and the tie rod assembly, inner to outer working as a parallelogram with as Shaun said, swinging in the same arcs. Using a bumpsteer kit, by lowering the outer joint, you're effectively making the centers between outer and inner tie rods longer, making it more closely match the centers on the lower control arm reducing unintentional steering is my thought.

I'm running 72 spindles with a Baer kit from Shaun with the same advice, all the shims in. Right now I'm experimenting with the shims. I started to make a bumpsteer gauge but I'm looking for some sort of a plate to use one the wheel. Right now my "dyno" is the crest in the road by my neighbors house to test, it works!

Years ago on the topic of bumpsteer Helmantel made a comment on using later spindles on the 65 - 66 cars that I didn't understand but some how knew it was Important. He said to run 5° caster. One day it hit me. The difference between spindles is this. The early ones have .500" more offset. The of the tie rod arm is about 6" long. long. Do the trig calculation and that works out to 5°. So in theory adding 5° caster on a 65 - 66 with later spindles as I see it, should put bumpsteer about the same as stock with factor caster settings.

Since my experience is with my car, I can't say exactly how it relates to the 67 and up. But one thing I believe is a big cause to a lot of problems is that the 65 & 66 simply have too much travel. I noticed on my car after I had the Baer kit in is that the rod end ran out of travel and bound up before the suspension ran out of travel. This toed the tires in and added some camber. I put 1" spacers under the shocks to limit travel. I have 1/16" clearance to the hood. It helps a little.

What I have read is a problem about converting a drag link to R&P is related to Ackerman. I don't think it's Ackerman by itself but how each system makes it. On a link it's created the angle of tie rod arms. On R&P it's made by the articulation of the linkage. On a conversion the placement of the rack is important or you end up with excessive toe changes since Ackerman basically causes a toe out condition in a turn for the different radius.

I'm not exactly sure how right I am but hopefully I have said something helpfull to someone.
 

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Hey guys I did this mod on my blue car. It was absolutely worth it. Yes, you also need to configure a 67 center link to fit . It's a bit of a pain but a couple things happened. Better camber gain was one, but also the car stayed much flatter than before in the turns. With the shorter control arms when the car dives the arms misalign quite a bit introducing a jacking effect promoting roll. This could not be fixed with springs and bars. It was a misalignment problem. When I put the longer arms in it allowed the arms to stay flatter longer throughout the travel reducing the jacking effect keeping the car more composed throughout the turn. I would do it again in a heart beat.
 

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Not sure how the 65/66 spindles would come into play or if the swap to 67+ spindles would be a good or a bad thing in this odd ball combination (they have a relocated tie rod arm.)
I never thought about it enough to realize there was a difference. I have 68 spindles and brakes on my 65 mustang. It was setup this way when I bought it in 91. I totally rebuilt/replaced the front and rear suspension years ago and had to use the tie rods that matched the 68 spindles as the 65 tie rods had a different thickness/taper spindle stud on them. Otherwise it has all 65 suspension parts.

A few years later my front KYB'S gave out at the track causing the suspension to rise dramatically. The car became an instant two handfuls of trouble trying to keep it straight going down the track. Needless to say, my bumpsteer is horrible, but I never really noticed it on the street as it stays pretty flat when cornering.

Years ago on the topic of bumpsteer Helmantel made a comment on using later spindles on the 65 - 66 cars that I didn't understand but some how knew it was Important. He said to run 5° caster. One day it hit me. The difference between spindles is this. The early ones have .500" more offset. The of the tie rod arm is about 6" long. long. Do the trig calculation and that works out to 5°. So in theory adding 5° caster on a 65 - 66 with later spindles as I see it, should put bumpsteer about the same as stock with factor caster settings.
This makes a lot of sense. I'm going to have to look into this. I am presently running factory caster settings, which by your calculations puts me at less than optimal actual setting. I also don't have a bumpsteer kit which isn't helping anything either.

I'm not exactly sure how right I am but hopefully I have said something helpfull to someone.
It's definitely helpful to me. Thanks for your input.
 

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Hey guys I did this mod on my blue car. It was absolutely worth it. Yes, you also need to configure a 67 center link to fit . It's a bit of a pain but a couple things happened. Better camber gain was one, but also the car stayed much flatter than before in the turns. With the shorter control arms when the car dives the arms misalign quite a bit introducing a jacking effect promoting roll. This could not be fixed with springs and bars. It was a misalignment problem. When I put the longer arms in it allowed the arms to stay flatter longer throughout the travel reducing the jacking effect keeping the car more composed throughout the turn. I would do it again in a heart beat.
Hey Mike, interesting stuff.

So did you mount the 67 LCA 2" inboard then on the 65-66 chassis?
 

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In the eighties I remember all the guys who were fast upgrading to the longer arms. It was a no brainier. There were a ton of positive things about the upgrade. So when we were developing the new MOD two suspension on the front of the coup we not only lengthened the lowers inboard, but we lengthened them outwards as well. The lower arms are roughly 3.5" longer now than stock. We kept the same roll center, springs and bar combo and the car was about 100 times better. I'll take bump steer all day for this upgrade. Now this is all well and good if we were just lapping around a track with no lap times, so... Recently we went to Sears point and did a few laps on our 200 tread wear Falken tires and we did 1:49.1's in traffic. To put this in perspective vintage TA cars are running 1:50's and current mustang challenge cars are running 1:48's on Hoosiers. Now I'm not saying this is the only reason the car is good,but it's defiantly a positive.
 

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Mike, now I'm intrigued:popcorn: Would it be worthwhile to attempt to swap the 67/8 longer LCA's on a mostly street car 66 coupe? Even to just improve everyday driveability (try NJ roads sometime, you'll understand). Would this just involve the stock style LCA's and the 67/8 inner mount structure? Was the track width effected?
 

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If the car is mainly street then it might be a little much. If your the type that likes to tinker and you are handy then why not. It will give you something to do. You will notice the most a nine tenths. I made my own arms and inner mounts when I did mine. It might be just as hard or easy to just replace the two towers. An afternoon of spot weld drilling and the towers come out. You can pick up those new towers pretty easily and it will all match. Plus the newer 67 and up towers have more room than the 65's.
 

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I absolutely love to tinker, that's why my simple T5 swap turned into a 7 year project.... I don't mind the full tower swap but I would like to keep the track width the same as stock for a 66. I'm assuming that would mean much shorter UCA's than stock.
 

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No, I wouldn't think so. Double check me on this but with the 67 and up towers are designed not to use the shims for alignment like the 65's. This gives the room which gets rid of the big bulge in the center of the tower. The tower is also 1" taller which allows for a longer spring which allows for a little better ride as well.
 

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More involved than simply replacing the shock towers. Would also want to replace the front strut supports for proper geometry.

Here's my write up that shows what should be done if upgrading to the 67-70 front towers:

http://forums.vintage-mustang.com/mod-custom-forum/827730-grafting-67-68-shock-towers-65-66-mustang.html

The pro's and cons of doing the project should be quite evident from that thread, with the worst being the increased track and me not knowing that the Arning drop should have been done at the same time.

I went a little overboard with the fancy clearance notch so this project took more than a couple of days to compete.

UCA's are the same length 65-70, its basically the tower bolt spacing that changed. The body was made wider to contain the added track from moving the towers outward. As stated, shims are not used on the UCA after 66'.

If space isn't a concern (as it was in my case) I would reused the 65/66 towers and try to relocate the 67+ LCA's as inward as possible without hitting the oil pan. Might need some custom brackets and a custom length LCA. Could still adjust UCA using shims if you didn't want to recreate the 67' variable LCA mount (Personally, I'd do the slotted inner mount upgrade and use the 67+ style and an eccentric.)

The steering wouldn't be too hard to figure out. Use the 67+ idler arm, centerlink, and a couple of tie rod ends. Use a 67+ manual pitman arm to mount to the 65/66 1" shaft when using manual steering. Might need the 67-70 spindles for correct tie rod location.
 
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