IRS Upper Control Arm

[Terry1]

Thought you might like to see this. ...not rocket science, but seems to be a fairly easy way to build a shorter, and adjustable, upper control arm for the t-bird IRS. The stock arm is waaay ugly, 10% too long and adjustable over a fairly small range. ...started with a 3/4"-16 LH rod end at the mounting point, added an 8" LH/RH threaded sleeve from JRMotorSports and made a clevis for the upright end of the control arm from a 1-3/4", 3" square tube with a 3/16" wall. ...drilled a 3/4" hole in one side and a 9/16" hole in each of the adjacent sides and then cut off the seamed side of the tube. ...finished the sides and ends on a belt grinder and deburred the holes. The clevis is attached to the sleeve with a 3/4"-16, grade 8 capscrew. The whole thing is adjustable +/- 1/4", accommodates the shorter (2"/side) axles and put together from commonly available bits and pieces. And, it is about half the weight of the stock piece and looks a whole lot better.

I know the lower control arm isn't going to be anywhere near that easy!

[LMH]

Terry
I'm not an engineer but shouldn't the upper arm be triangulated?
It is on my Hurricane and it's really stout.
Larry

[Jay Little]

My brother did basically the same thing on his FFR Daytona kit.

[Terry1]

Jay, Thanks for the back up. I knew that couldn't be an original idea! The photo of the stock item in back of the one I did is off of a Super coupe - nothing but an open bottom channel. The Super Coupe guys that have higher horsepower setups box the bottom of the channel - That's on a car that weighs twice as much as a Cobra replica. I'd be very interested in how your brother's set up worked out for him. And, how he did the lower control arm to replace that gargantuan cast steel a-arm on the Super Coupe. I'm still in the measuring and drawing stage so now is a great time for input from all the guys who have done this before. Incidentally, I'll be tickled pink if I get 300 hp (flywheel) horsepower from the little 302 I'm going to use and this is going to be a stree-use only car with an AOD.
Terry1

[fasterpatrick]

Hey Terry would you be interested in this,


I have drawings for this setup would you be interested. Patrick, Tons of pics in my gallery

[Terry1]

Patrick,
Actually I drool all over my keyboard looking at the the pics in your gallery every night. I've got to get up to see your car sometime this fall! I'm light years behind what you are doing but yes, your lower control arms are conceptually similar to what I would like to do.
Terry1

[fasterpatrick]

Terry, actually I'm having a gathering the morning of Sat. Sept.15 ( 9:00am - 12:00pm ), for the gear-heads I hang with from around here. If you need an excuse to show there should be a number of cool rides to see, weather permitting. Other wise just give me some advance notice and I'll give you a private showing. Pointers and advice are always free. Patrick

[strictlypersonl]

Originally Posted by LMH

Terry
I'm not an engineer but shouldn't the upper arm be triangulated?
It is on my Hurricane and it's really stout.
Larry

On the Mustang, they brace the top of the hub carrier with a longitudinally-mounted damper ("Quad Shock"). The lower control arm is still put in twist-stress so there's some "slop" in the hub carrier location, but the damper is supposed to keep that under control.

[Terry1]

Strictlypersonl,
The 'damper' sounds like a nice idea. ....will check that out. Should be pretty simple to implement also.

Patrick,
Thanks for the invitation to your gathering on the 15th. ...looks as if we get to have family here that weekend so I won't be able to make it. Also, I think I have your drawing on that lower control arm - will check the pages I have and PM you.

Thanks again to everyone for your ideas.
TWM