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Topic: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars (Read 3108 times) previous topic - next topic

How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars

Evolution Motorsports has just release the Tri-link rear suspension for the Mustang and I was wondering if it would also work for Fox T-bird/Cougars. I've PM'd a guy from EvM (Evolution Motorsports) and he asked...
1. If the control arm lengths were the same.
2. If the rear floorpan/UCA arrangement were the same.

I know the control arms are different lengths, but I don't know by how much. A longer third link may be able compensate for this difference.
I haven't a clue if the floorpans are the same.

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars'

Reply #1 –
The floor pans are "similar"

The Tbird lower arms are about 3/8"-1/2" longer than the Mustang ones.  Don't remember exactly how long as it's been a while, but I did have them side by side on the bench at the shop when we R&D'd the TBird control arms at KBs.

I do remember that the uppers at 1 1/8" longer (10.25" vs 9.125").

What are you planning on for a lateral locator?  The TBird gas tank is a big SOB and can get in the way of alot.

I actually sketched out something similar to the EVM design 4-5 years ago but never followed through with it...guess I missed my chance, huh ;)
Long live the 4-eyes!  - '83 Tbird Turbo

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars'

Reply #2 –
I made my own lower ones and boxed in the upers and added polys

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars'

Reply #3 –
He's not asking about making stock replacements, he's asking about the feasibilty of using the EVM 3-Link on a Tbird....
Long live the 4-eyes!  - '83 Tbird Turbo

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars'

Reply #4 –
I was looking in to there tri link to but one thing I was somewhat concered about was the mouting bracket for the axle it self. I looks as if there could be some clearance issues on a lowered car so I decided to stick with fords original design  but make all my control arms out of dom tubing with spherical bushings. As for the length of the tri link itself I think They could give you an adustable one but you might need one specifc to our cars. The factory four link set up is a good design but you need to get rid of any binding that may occur in articulation of the axle.

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars

Reply #5 –
Quote from: Chuck W
The floor pans are "similar"
The Tbird lower arms are about 3/8"-1/2" longer than the Mustang ones.  Don't remember exactly how long as it's been a while, but I did have them side by side on the bench at the shop when we R&D'd the TBird control arms at KBs.

I do remember that the uppers at 1 1/8" longer (10.25" vs 9.125").


Hmm, seeing as Mustang and T-bird UCAs leave the axle at the same angle (laterally), the distance between the upper UCA mounts will be a bit wider on the T-bird than the Mustang. Looks like the chassis mount of the Tri-link won't work. Correct?

Quote from: Chuck W

What are you planning on for a lateral locator?  The TBird gas tank is a big SOB and can get in the way of alot.


An MM or Griggs panhard bar should work.

Quote from: andrew beedle
I was looking in to there tri link to but one thing I was somewhat concered about was the mouting bracket for the axle it self. I looks as if there could be some clearance issues on a lowered car so I decided to stick with fords original design but make all my control arms out of dom tubing with spherical bushings. 

Although the Tri-link is hot off the press, nothing I've read has mentioned anything about clearance issues. My only worry is the sheetmetal tearing from the chassis mount. The mount does channel loads into the UCA boxes, but I'm not sure if it’s enough.
Do you autocross/open track/drag race?

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars

Reply #6 –
I've never measured between the UCA mounts to compare between the two.

 It's possible the amount they might be different is compensated by the rubber bushings.

You may need to take a couple measurements and gove them a call and see.
Long live the 4-eyes!  - '83 Tbird Turbo

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars

Reply #7 –
I am not one to race my car but I seem to think theres no reason to reinvent the wheel. Fords original design was good in my opinion it was just really sloppy because of the rubber bushings used but the intent was probably more toward comfort then handling. If you want a expert opinion I would say stick to what chuck w says because he has the experience to back up his knowlege from working at Kenny Brown.

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars

Reply #8 –
Well, the original Ford design was more for economy than anything.  For any real aggressive driving the stock 4-link just does not cut it.  If you firm things up enough to compensate for the sloppy bushings, you compromise the articulation of the system and cornering ability is hindered.  The rear roll center is WAY too high as well..something like 16-17" from the ground.  It works out ok in stock form because the stock front end will understeer the car off the road before the rear end will become a problem, but once you start tightening things up and improving front grip, the deficencies if the rear suspension become glaringly apparent.  EVMs 3-link idea is pretty interesting and like I said, you may have to do some leg work yourself and climb under the car and see how they compare.  Adjusting the arm lengths won't be an issue, it's the chassis mount for the upper arm that is the issue.
Long live the 4-eyes!  - '83 Tbird Turbo

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars

Reply #9 –
Quote from: andrew beedle
I am not one to race my car but I seem to think theres no reason to reinvent the wheel. Fords original design was good in my opinion it was just really sloppy because of the rubber bushings used but the intent was probably more toward comfort then handling. If you want a expert opinion I would say stick to what chuck w says because he has the experience to back up his knowlege from working at Kenny Brown.

I was just wondering because I saw in another thread that you were fabbing up some LCAs/UCAs with solid bearings in both ends. Solid bearings in the UCAs won't help with cornering (drag racing is another story, but I'll stick to lateral performance).

Re: How do Mustang UCA/LCA lengths compare to Fox T-bird/Cougars

Reply #10 –
I did make my own control arms but the bushings were not solid, they are spherical bearings which have no binding at all. They allow complete articulation but keep the axle located. Here is the link to what I purchased http://www.stockcarproducts.com/susp3.htm
I basically made an exact replica of these arms for 1/3 the price http://www.bmrfabrication.com/Mustang.htm