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Topic: Which rear control arms to get? and some tire size advice (Read 870 times) previous topic - next topic

Which rear control arms to get? and some tire size advice

I'm planning to get some rear control arms from che performance, uppers and lowers.
So what I'm really interested is in the height adjustable lowers and regular uppers.

Currently for the rear it's pretty stock except for the 3"exhaust which still needs to be fixed since it rubs on the rear axle when loaded or going over big bumps
My planned end result will be fr500s 17x10.5 wheels with the 5lug conv. (via sn95 axles, mpv van rotors, and 1/8 spacers), rebuilt Trac loc, chucks shock adapters, some sn95 or fox shocks, lower it with sn95 or cut tc springs, and the che control arms

Should I opt for the adjustable uppers for correct pinion angle or should I be good without them?

Also for the lowers I like that I could be able to adjust the ride height, but I was reading up on a thread on here where a member was switching to the regular LCAs because of ride height issues. I can certainly see how the adjustable version will give you a slightly higher ride height right off the bat because of the actual adjustment mechanism on the arm. Hopefully I won't run into any issues but if anybody sees a flaw in my future setup, I'm open for suggestions.

And one more haha, tires.
I'm not gonna lie, I'm pretty clue less when it come to tire sizing except for the diameter. Anyways I need to know what size I should go with. I've talked to razzys wagon here on the forum (who also has an awesome TC on some fr500s) and he's running 315s. So I might go with those.
I wanted to note that he also said the tires rub when the cars is loaded down, his proposed fix is mustang length axles which will tuck in the wheels 1/2" on each side.
Does this sound like a good idea or should I just get a tire is less wide???
Idk hopefully I can get advise before I get the wrong stuff

Thanks
1987 T-Bird TC: 5-Spd, 5-lug conv., CHE Rear CAs, '04 Cobra wheels and 13" Brakes, Vac Assist conv: '93 Cobra BB/MC & Wilwood PV, Gutted/Knived Intakes, T3 turbo, RFE6 Mani, Stinger 3" Exhaust & Oil Feed, 255HP Walbro, Kirban AFPR, RR Cam, Esslinger Cam gear and Round Tooth Conv., Gillis Boost Valve, Speedway Dual Valve Spring,  K&N, 130a 3g Alt conv., 140mph Speedo
Running Better Than Ever :burnout:

Which rear control arms to get? and some tire size advice

Reply #1
I have adjustable uppers and they are really nice for adjusting pinion angle, which is almost always a necessity if you are going to lower the car (you might be fine w/the spring setup you have planned though).  I had adjustable lowers for awhile, as you stated they do raise the car compared to the non-adjustable ones.  I had Steeda Fox Mustang springs for awhile and they sagged really badly, hence the adjustable LCA's.  After a few years I decided I was tired of the car riding like a log wagon and sped the Fox 'stang rear springs for some cut down turbo coupe ones.  At that time I swapped to non-adjustable LCA's.  Car rides a lot better now, especially with the addition of Chuck W shock adapters and Fox Mustang Tokico shocks.

With a stock height rear spring and adjustable LCA's, you would have a "sting bug" stance IMO.  Unless your springs sag or are really going to make the car low, I don't see the need unless you are running tall slicks or something like that and need the clearance.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube