What rear end housing is in supercoupes

SVT_BIRDSC

Registered User
Looking at putting gears in my supercoupe anyone kno weither to go 3.73 or 4.10 and need to kno what kind housing the cars have
 
auto or manual? and it all depends on what you do, 4.10 is a little bit much IMO for a daily driver, espically if your on the highway. IF it was an auto Id go 3.73 .......stock are 3.27 for the autos, I dont know about the manuals.
 
Its a 5 speed car i think 4.10 is oo much too so i might do 3.73 if somebody had some in their car could tell me how it they are i will do 3.73
 
what year SC ?

the later models had a longer first gear than than the early ones. if u go with 3.73 u might as well kiss your 1st gear goodbye. it would be damn near useless. your gas mileage loss would be horrible . and you'd be in very high rpms when on the highway.

i have an 89 5spd and i've done quite a bit of searching around here and i'm going with 3.08. it seems to be a happy medium between stock(2.73) and 3.27. it still gives a good pull in the higher gears and doesnt decrease gas mileage much. and the best thing about em is i can run thru the traps at the strip still in 3rd gear. whereas if i had 3.27's i'd be shifting into 4th right at the end. and i dont want that.

u can go ahead and put 3.73 in there but i think you'd be changing your mind after a few weeks. unless your SC is goin to be used for drag strip purposes only i wouldnt go any higher than maybe 3.55's. for everyday driving, 3.08 and 3.27 seems to make everyone happy.

one more thing : make sure you have enough rubber back there to hold the power those 3.73 will put down ! if u decide to go that route.:)
 
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I switched fromm stock 2.73 to 3.27 in my 93 manual. I am fine with this change. I would not go higher than 3.27 for myself.

Jon
 
Gears Post 2 Question

my brother has a 96 mustang cobra and is doing 4.10 gears and he said i could have the stock 3.27 for my 1990 thunderbird supercoupe well they fit my car cuz everyone is saying that 3.73 is too much so since the 3.27 is free i will just use them if they will fit and how big of a differences would it feel like in my car
 
my brother has a 96 mustang cobra and is doing 4.10 gears and he said i could have the stock 3.27 for my 1990 thunderbird supercoupe well they fit my car cuz everyone is saying that 3.73 is too much so since the 3.27 is free i will just use them if they will fit and how big of a differences would it feel like in my car

as long as its an 8.8 inch it will work
 
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Any 8.8 in the Bird

as long as its an 8.8 inch and 28 spline it will work

Sorry, but the spline is in the carrier gears where they mate to the axles, not the ring gear and pinion. You can use virtually any 8.8 RG-P in the Tbird. The 3:73 really isn't bad in an auto, I've got a '95 auto with a mark VIII aluminum pumpkin and 3:73 gears. fuel milage really didn't take much of a hit either. Big seat of the pants difference in punch. The 3:27 should be a good upgrade for you from the 2:73. You will feel the difference. since the carrier has to come all the way out to switch out the gears, go ahead and put a clutch rebuild kit in while your at it. FRP kits are less than $50 and well worth it to do while the pumpkins out. Also consider a complete carrier rebuild kit with new bearings, crush sleeve, carrier shims etc. You will have to have the crush sleeve anyway for the pinion. I got a great price on a Yukon kit on eBay.
Oh, one thing though. If you put in used gears, get ready to put up with some whine for a while until they get seated in. Mine were from a totaled Explorer with only 10k, and they whined pretty good for the first 1k or so. My rearend guy told me that since they had already started to wear in on the old carrier, they wouldn't mesh perfectly until they wore in with the new setup.
 
IRS rears have side gears machined to accept the circlips from the axle shafts. Otherwise they are similar to any 8.8" ford Rear
 
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