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im gay as hell
04-10-2005, 10:42 AM
which one is more popular and waht are there ups and downs for a 1987 5.0 t bird

81T-bird
04-10-2005, 02:03 PM
Gonna depend on how much highway driving you do. If you had a 4.6 car I would say 4.10 no questions but for a daily driver w/ a 5.0 and auto my vote is for 3.73s.

shame302
04-10-2005, 02:06 PM
okay dude.
a few things to think about. 373s are way more popular as specially on the street. on the dragstrip however 410s are going to be a better choice. more so for an AOD car than a t5 car.

worthy of note is the 5.0 SO is all done at basically 4500 rpm. while you will feel alot more acceleration you will actually run out of motor. the HO is "good" for 6250rpm (rev limiter/redline)

if you are thinking of gears id go with 373s. in fact the turbo coupe rear end im rebuilding is an 8.8 with 373s. im actually a little comcerned that they might be too steep for the street, highway and T5.

again, i wouldnt realy bother with having someone install gears in a 7.5" rear diff. i would be more concerned with getting a 8.8 in there reguardless of the gearing.

an 8.8 rear from an 86 older turbo coupe will be easier to install because it still has drum brakes. if you go with an 87-88 turbo coupe 8.8 you will have to convert to rear disks as well. this is alot more involved as specially if you want to keep the use of your e brake.

if you can find a tbird sport in the junk yard (make sure its actually a sport) they at least have a traction loc rear diff even though its a 7.5" rear. the gearing in most of them is tall, 273 but apparently some of them had 308. the trac loc is a big improvement over the open diff version and should last awhile with an aod and mild engine.

chances are though the junk yard is going to charge the same for a 7.5" as an 8.8"

im gay as hell
04-10-2005, 10:10 PM
but if i install the 373 i should be faster than another tbird with out 373 or would i be able to peel out alot more than what i could know

shame302
04-10-2005, 11:11 PM
well, say if both cars are exactly the same other than the gears (373 vs stock say, 273) then the car with 373s will take off and speed up quicker then the car with stock gears. the car with the stock 273 gears will have a higher top speed.

as far as peeling out, you probably have an open rear end now. if you keep it an open rear end then yes, it will peel easier. if you upgrade to trac loc even with the 373s you will have more traction. tires will be harder to spin.


Edit:
another classic thread

Bird351
04-10-2005, 11:24 PM
Edit:
another classic thread


Yer not kiddin'.

Bob
04-10-2005, 11:37 PM
I switched from 373s/t-5 to 355s/t-5 and when I had my aod I liked the 373s...

shame302
04-11-2005, 12:55 AM
I switched from 373s/t-5 to 355s/t-5
yeah, ive been thinking the 373/8.8 i have to go in my birds gonna be a little steep. i dont use it as a daily driver at all but id like to be able to cruis at 65-70 easilly on the highway.

were the 355s much different compared to the 373s, thay are so close...

TurboCoupe50
04-11-2005, 04:01 AM
yeah, ive been thinking the 373/8.8 i have to go in my birds gonna be a little steep. i dont use it as a daily driver at all but id like to be able to cruis at 65-70 easilly on the highway. Even 4.10s ain't nuthin crusing in OD/5th.... With the 5 speed, its 1st gear that is almost useless with about anything more than 3.55s, because of the deep 3.35 ratio of 1st.

The Ford Racing T5 with 2.95 1st is a lot friendlier.

81T-bird
04-11-2005, 07:15 AM
With a 5 speed I'd probably go with 3.55's if I drive it alot. It'll get you a couple hundred RPM back.

My buds who have road race/street cars, like 3.55 in the rear better than 3.73 because they aren't shifting in the middle of turns.

im gay as hell
04-11-2005, 04:23 PM
so should i even change gears if its gonna reduce my top speed,by how much does it reduce it by , let saywith sock gears my catr rund 100 and with the 3 73 what will the numbers be because i though that it would make a big differencebut if it doesnt ill leave them stock

Tbird232ci
04-11-2005, 04:34 PM
youll never have you car fast enough to notice the difference in max speed honestly, i have 3.55's in my turbo coupe, with a 5-speed, and i pulled about 125mph, and the car kept pulling

its really worth swapping out a rear with 3.73's in it, especially in an automatic car, its one of the best mods you can do for a good gain

SirChirpAlot
04-11-2005, 06:34 PM
Well i have 4.10s with a T5 and 28inch tall tire.
I do more intown driving then highway but i still do 150 175 Kms to and from the shop with no real probs except for my gas going bye bye.
I run with flow on the HWY with no probs as well.

As for 3.73 or 4.10 if u want to make the car faster out of the hole the 4.10 will do that better then 3.73 but 3.73 will be easyer on u when u do alot of HWY driving.

If your motor is stock or mild then u dont have power and RPM range to make best use of 4.10s so 3.73 would be a better choice in my view.

But something alot of
stang boys are doing is going with 3.90 gear. U get some of both worlds with this gear.

im gay as hell
04-11-2005, 10:07 PM
the turbo coupe topspeed, is it more than a regular tbird 5.0

dominator
04-11-2005, 10:09 PM
yep

shame302
04-11-2005, 11:54 PM
the 5 speed is anyway...

Tbird232ci
04-12-2005, 12:31 AM
it is higher than a 5.0, but we're never going to max out our cars, the suspension, tires, roatating assemblies (driveshaft for one), and other odds and ends make for a scary ride at such high speeds

my 3.8L bird got scary around 95-100mph

lowcat
04-12-2005, 06:29 PM
Yo word on the street is electric superchargers give you some crazy mad power yo, pair that with some 4.56's an you will be extreme go fast racing yo:rice: Maybe you should look into that.

Haystack
04-12-2005, 06:57 PM
i got my stock cougar up to around 130 mph, but that was just insanity. I would recomend that no one ever try that. If I would have just twiched and moved the steering wheel i would have died.

im gay as hell
04-12-2005, 09:12 PM
so could i take the computer out of a turbo coupe and put in a 5.0 or a cougars computer to make the car faster

Thunder Chicken
04-12-2005, 09:34 PM
No. A turbo coupe is a four cylinder. A Cougar has the same computer you do. The problem with the 5.0 SO engine is not the computer anyway, it's the breathing. The heads, upper intake, throttle body, and exhaust manifolds are all very restrictive, and the cam is very low-po. The only way you're gonna get any reasonable power out of your engine is to replace all of the above (in other words, do a HO conversion). Once you do the HO conversion you'll need a Mustang computer because your SO computer would not know what to do with all that extra air (plus it would now have the incorrect firing order because the Mustang cam changes it)

289Cougar
04-29-2005, 11:47 AM
Yo word on the street is electric superchargers give you some crazy mad power yo, pair that with some 4.56's an you will be extreme go fast racing yo:rice: Maybe you should look into that.

HAHAHA nice, but you forgot one ricerific fact, stickers make horsepower!