Hi I have a 1988 thunderbird sport with the 5 liter v8 in it and I'm pretty sure it has a 7.5 rear end in it. I want to do a swap to the 8.8 rear end but i dont know where to get one. I also want to know if a mustang 8.8 rear end would work or maybe a f150 rear end. I know the turbo coupes have 8.8 rear ends but they seem like they are rare in junkyards. Please help and thank you to whoever helps
:D
A Stang 8.8 will work, but the axles in the Bird are longer. A Turbo Coupe would be a great way to get it all. 8.8, good gears, disc brakes. I BELIEVE a rear from an '94/'95 is the right width and will also swap in with a little effort. There's more, and I'm sure somebody else will chime in for that info.
Thanks (: I heard the 7.5 can only handle 350hp and I want to go above that so Im highly considering the 8.8. I have underdrive pulleys, a 65mm throttle body, and a full fuel exhaust with an h pipe and flowmaster 40s. I'm planning on aluminum heads and a new intake so I'm gonna need to strengthen my rear end for sure.
if your lucky it will handle 350 hp lol i had one snap on me just like that. also i would change out the gear ratio you dont want thoose .273s in there if your pushing that much horse
I wanna put in 3.73s
thats what i have in my 8.8 its alot better if you dont mind losing some fuel economy
Yeah I don't mind. I need a reliable rear end or else im
Just gonna snap what I already have. I'll probably do the swap when I'm around 300hp
i dont know it depneds on your driving i mean i snapped my 7.5 with around 250 horsepower but i was 16 and always roasting my tires. i blew out my center carrier. id go with 8.8 ( turbo coupe to save alot of hassle in setting it up) then get 3.73 with full posi or a locker for the love of god dont spool it lol its just not safe. but its all about what you want to do
Yeah I want it to be a street and strip car. I wanna go up to about 400hp and just have a fun ass car to drive around. I think the fox tbird look better than the fox stangs. But my tbird I have now was my mothers she bought it new in 88 and then gave it to me it only has 89000 miles on it so It has plenty of life left in it. It's a 5.0 that I'll
Probably convert to H.O
I wouldn't worry about the rear too much. The v-6 stangs had them stock and they were 215hp+ in the later years. I wouldn't worry about it until you get to running slicks or big tires. I've had a few 7.5's well over 200k miles without issue.
The 94-98 stang rears would be a good swap if you go 5 lug. Some of the sport and xr7's had 8.8's in 88 and you could always swap the ratio in you want before taking the rear to the checkout ;). My 88 crownvic wagon has a posi 8.8" rear with 3.55's from the factory.
I've got a 7.5 in my car with all the mods listed. I've drag raced it multiple times with no ill effects. I have not run drag radials or slicks with it however, just street tires. Spinning is not what will kill it traction will ;).
I do have an 8.8 out of an 88 Cougar XR7 in the garage. It's a drum brake setup like stock. It'll find it's way under the Thunderbird some day when I get the gumption to swap it in.
If I do go with the 94/95 stang rear end and go 5 lug is there a conversion kit for the front to go 5 lug?
Too bad you're not in Virginia, I could fix you up. Find a Turbo Coupe with automatic and they already have the 3.73 gears.
You have several different options.
You could run 87-93 stang spindles and mark 7 discs, upgrade to the 94+ setup or even just get stock sized discs with 5 lug already.
Do a quick read on coolcats.net. it covers the swap pretty well.
Just curious what type of 5.0 do you have that is strong enough to break a 7.5 ??? The 7.5 is no world beater but it can handle more HP than people thing!! Basically the only difference in the ring gear. The axles are identical and carry the same part number. A good setup 7.5 is no slouch. I have run them with 300-350 Wheel HP with no issues. Just saying!!
I have 2 8.8 TC rears in my trailer collecting dust. They are around you just have to look harder.
Locate a 94-98 V6/GT Mustang rear end and it is the width you want for the T-Bird. The 99+ cars are wider and the rim selection goes south real quick. Figuring out what gears the car has is pretty easy by using this method if the rear end is still in the car or on the ground:
With a standard open (non posi traction) differential raise one wheel off of the ground, mark the tire at the 6:00 position, mark the drive shaft. Turn the tire exactly 2 full turns. Count the number of times that the drive shaft turns. 2-3/4 turns of the drive shaft = 2.73, just past 3 turns = 3.08, 3-1/3 = 3.23 or 3.31, almost 3-1/2 = 3.42, just past 3-1/2 = 3.55, 3-3/4 = 3.73, just past 4 = 4.10 or 4.11. With a good solid limited slip differential (posi) raise both wheels off of the ground and turn both wheels exactly 1 full turn. Everything else is the same as above. You can also do this with a standard differential as long as both wheels turn exactly 1 full turn.
Darren
We have MULTIPLE threads concerning this subject on the forum. One of which, found HERE at the top of this very section (http://www.foxtbirdcougarforums.com/showthread.php?13253-Deciphering-Fox-Axels), has a chart detailing dimensions, etc of the 79-04 rear ends.
For some reason this does not sound right. Are you saying an open rear multiplys by 2. I will have to check that before commenting. You might be right. Just does not sound right for some reason. Need to research this!!! That would mean the spider gears are a ratio of exactly 2-1. Is that correct. I personally do not know???
Tom,
I got the best explanation for this here:
http://www.jedi.com/obiwan/jeep/misc/gearratio.html
I have never had an open differential so this is something I am not 100% about. I read this (worded differently) on several different what I consider reputable sites so I did not hesitate posting it. Maybe I should have eluded to that in my previous post. I would be curious to hear your take on it and if its BS I will edit my previous post.
Darren
If the rear end being shorter is a concern, ill just say that when i put in a fox rear, i like the fact it pulled the tires in. Im running 9.5 rears so it gave it a more streamline appearance instead of having them stick out. But you can always buy spacers if you want.
SPACERS!!!!!! Just me but i never use them.
http://www.maximummotorsports.com
They sell 1/8", 1/4", 3/8", and 1/2" spacers and they also sell thicker ones that bolt to the existing studs and have a set of studs to bolt the wheels to. These are obviously hubcentric.
Darren
I run a thick bolted on spacer on my truck they seem a lot safer