Visit The Dirt Forum for More Information

Author Topic:   t-birds
dirtpoor racing
Dirt Full Roller

Total posts: 29
posted June 10, 2004 08:36 PM  
I read in a previous topic about the later t-birds that have the independant suspensions.Just curious if anybody ever got one setup to handle are would staying with a straight axle be the way to go. thanks

Dirt Forum Champ
Total posts: 5390
posted June 11, 2004 04:57 AM  
Even though its a stock peice, it might not be legal. Gear selection would probably a big hinderance as well. I also would suspect that the CV joints wouldn't be able to handle much horsepower at all. Anybody used one that can prove me wrong?

Dirt Forum Champ
Total posts: 635
posted June 11, 2004 12:28 PM  
They don't have a full frame. However, they have a decent rear subframe to work from. Most tracks don't allow independent rears even if it was stock.

The front spindles would bend quite easiely, rears would take quite a hit before the suspension broke. The C-channel stamped upper arms would be the weakest link.

They also use a 5 x 4.25" bolt pattern which makes wheel selection a pain or just redrill them for 4.5" pattern.

The center section is a typical 8.8 gear (on V8 and SC models Base got a lame 7.5), so gearing selction isn't an problem. A spool would have to be specific for an IRS car (newer Cobra's used IRS too) because the carrier has a ring cut for retaining the CV shafts.

The CV shafts themselves can handle a TON of abuse before they break. My SuperCoupe makes over 400 ft-lbs at the wheels at 3200 RPM. I just broke the stock, 193K mile left side shaft Memerial Day weekend. I guess it couldn't handle the 1.78 60' times and Hooiser Quick Time Pro's. There's a company in Fla, Raxles, that makes axles to replace the stockers (pricey at $250 each, but equal to a Moser solid axle). They use race spec joints that have withstood low 11 sec 1/4 mile runs with 1.5x 60' times in SC's putting around 500 ft-lbs to them with 11" slicks.

If you're allowed to run them, the adjustable rear end (chamber and toe) would be a huge advantage on dirt. You'd just have to be careful not to let people bang on the front end too much. The spindles and strut rods would tweak pretty easily.

Dirt Forum Champ
Total posts: 569
posted June 11, 2004 01:43 PM  
I stand corrected.

Dirt Forum Champ
Total posts: 1363
posted June 11, 2004 02:20 PM  
i almost built one of those things, but all the tracks around here outlawed them after another guy built one and was spankin' everyone.

the only problem i see with IRS in a high horsepower dirt application is no anti-squat...

dirt poor racing
Dirt Full Roller

Total posts: 75
posted June 13, 2004 03:53 PM  
we are runing an 80 t-bird now we had to brace the front strout towers off to the fire wall, car has took tons of fender rubbing and two solid hit to the front end and so far keeps on going (only FORD in our class) someone gave us the 91 t-bird and we was wondering if it would be worth the time and effort. THANKS..

Dirt Full Roller

Total posts: 46
posted June 14, 2004 07:14 PM  
Try Racer Walsh they may have the answers to your IRS questions. We run a 85 Bird and love the car they are much more than a lot of people realize. We wish you lots of luck!

Dirt Maniac

Total posts: 136
posted June 15, 2004 08:34 PM

This is my '89 T-bird, 1st race car so am really slow right now.
Welded in a 2X3 square tubin Sub frame from
front to rear.
1st night out had right front tire rubbing
top of suspension.
Haven't adjusted toe or camber yet, just making some laps.

rear-end locked with mini-spool,
stock 3.27 rear gear with 3 speed in 2nd gear.
Racing springs all four corners,
Koni shocks on front, bilsteins on rear.


Back to the Archives