gonzz

I was wondering who has granyy 8.8 rear. I'm going to order mine in 2 weeks and wanted to know if the people running them would do anything different if they had to do it again.... What gears to get also?.. I'm thinking 3:73's. Thanks for any info.

evita

Where do you purchase one of those? I'm interested...I don't think I've ever seen that before.

EDIT: Answered my own question

http://www.grannysspeedshop.com/

evita

I dunno...after looking at it, you still have to use the watts set up to locate the rear end side to side. I guess if you were using a V-8, the torque figures would be much higher, thus the necessity of a killer rear end.

I would only change my SE set up by adding a tri-link and panhard bar.

I do like how you can choose your gear ratio however....

Guess it depends on what you need your car to do.

z-beater

Why not ReSpeed's new rear-end kit that is supposed to come out? The 8.8 is great, don't get me wrong but IMO it creates a lot of parasitic power loss.

EvilJester

could you expand on that a bit more...im not shure what you meen.

dj55b

iTrader: (2)

the heavier the components the more power loss through the drive terrain, hence the terms flywheel horsepower (power made at the Flywheel), Wheel horse power (the actualy number of horse power left to run the car, the lost HP is equated into moving the flywheel, transmission, drive shaft, rear and gears, rear axles, brakes's and obviously wheel) this is why they make lighter components such as Aluminium flywheels, aluminium drive shafts, and things like that to have more "usuable" HP at the wheels.

85rotarypower

The Respeed kit is just axles drilled to a specified bolt pattern when you order them. They don't strengthen the rear end really. The axles themselves are stronger, but in most cases its not the axles that break. Thats one of the strongest parts of the stock axle assembly.

As for gears, I would suggest stock 4.10 or even 4.44 to compensate for the added weight of the rear end.

gonzz

When you get above 400 RWHP the stock rear end will not last. Some people say it will but let's face the facts. The stock rear was made for how much HP? The 8.8 might add 50 lbs but is that a big deal for a great rear end that can handle anything you throw at it.. It's the best option in my opinion. I'm ordering it next week so I will let you guys know...

DriveFast7

iTrader: (1)

hi steve,

is that a torque arm suspension? welding it to the axel would be lighter and stronger than bolting it to the diff cover in single shear.

in the first pic, what is the black link in front of the axel?

if instead of the big center conglomeration of tubes you did a 3rd link from ontop of the diff, thru the floor to a bracket on the crossmember it would be a lot lighter.

as for ratio, why not something in the low 4.00's.

twinkletoes

iTrader: (17)

Steve will defintaley need to upgrade his rear end (thats sounds funny) with the setup he is going to be doing. It will be heavier, but will great imo. He will also have to give me a ride sometime . I think you are doing the right thing steve. Keep us posted.

Dan_s_young

iTrader: (1)

The parasitic power loss from the heavier built differential should be pretty minor the extra reliability and longevity that you will recieve will make it worth it.

As far as gear ratios go you need to be careful because you can actually make the car a little slower by choosing a gear that is too low.

Also with the 8.8" you can use mustang brakes out back IIRC.

Gonzz were you able to talk to Grannies online or did you call them and talk to them? I emailed them a while back, but I have heard many stories about them not writing back, and I never got a email back.

I will be following in your footsteps soon, but I have other aspects of my project I need to work out prior.

Also I like the concept of the rear end lifting under accell/load. But wouldn't that have the tendancy to lower the amount of traction out back?

gonzz

I called them. I'll let you know after i get it installed.

gonzz

I was told a 3:73 is my best option when running 15" wheels. It's not a 1/4 mile car.. Just a fun street car. I think Directfreak is running the same gear ratio also

trochoid

iTrader: (6)

For a V8 swap, 3:73s might be ok, but not on a rotary with an 8k redline. With the 15X7s I'm running now, net gear ratio from the stock GSL rear is near 3:73 on mine now. To have my speedo read correctly with the 245/50/15 tires, I need 4:33 gears.

gonzz

you running a TII trans? My speedo is showing different than yours then. But I'm running a S5 TII trans and 5 TII instrument cluster in my car..

Dan_s_young

iTrader: (1)

For interest sake how did you calculate this out? Did you use a calculator of some sort on the internet to figure out the actual number?

I know since I am running 17" (315/35/17 rear tires) rims my gear ratio is going to be different, but I dunno if my gear ratio decision is going to be in order to correct the speedometer... But instead for the best overall performance.

trochoid

iTrader: (6)

Took a stock tire and wheel, along with the 15" one, marked a spot on each, rolled them on the floor and measured the distance traveled. I was also stopped speeding. Had the speedo sitting at 78/79, clocked at 87. Don't remember the measurements off hand, but the difference was around 9-11%. Didn't get into the heavy math, I estimated in my head and could be a bit off.

Nice thing about Ford gearsets, they're cheap. Track testing with different sets will show the optimum ratio.

Dan_s_young

iTrader: (1)

My biggest complaint about the 8.8" is that it's overhung and it's not a removable carrier... These are the two reasons I wanted a 9", but I don't know if the extra weight is justifiable. But either way the cheap gear sets is a HUGE plus.

katorx7

Hey Steve there are several schools at my control tower that can help you get your pilots license for that airplane you drive on the street.

Here are some pics of my Grannys 8.8 set up. Order the adjustable heim end suspension setup it will help make the install cleaner and easier. Also the suspension will work better.

I should have this in the car next weekend.


Granny's Speed Shop
Truck housing 8.8 Ford diff (more material, larger, approx 10+ lbs heavier)
3.73 gears, Detroit Locker, Alloy racing axles, longer wheel studs

Custom adjustable heim end watts link, custom adjustable heim end lower control arms

M/T ET Drag wheels (11 lbs)













[/QUOTE]

gonzz

FYI.. his 8.8 setup is for a FC...Looks sweet..

Dan_s_young

iTrader: (1)

That looks awesome, I can't wait until I can get mine! I'm sure shipping will be rediculous though...

gonzz

They quoted me 350.00 shipping for mine to Las Vegas

katorx7

Wasn't too bad. Total for shipping was $200.00. (1) crate-truck freight, (3) large boxes USPS.

My order took about 2 1/2 months because of the truck housing, detroit locker and the heim end suspension parts. Well worth the wait.

Directfreak

iTrader: (2)

That kit looks great!!
More like 100 lbs.. *sigh*
I would've gone that option if it was available at the time.
Yes, and you will love it. The turbo will actually be able to use the gears, instead of just spinning the tires. My 3rd gear goes to 110mph at 7000 RPM.GSL Rear is 3.90(09) On a Turbo car, a heavier rear end, and lower gearing will actually increase load, this spooling the turbo much faster. It will also be better to move forward, rather than spinning the wheels. I suprise people very much, as my car scoots and goes, and rarely loses traction when accelerating. (unless I want it too ). For a street car, -it's a great option.
For a drag car, the 4.44's would be fast (with slicks) but just plain suck on the road.

http://www.f-body.org/gears/

That's why I went with an 8.8, with 9" ends, thus no "C" clips,and big bearing ends. All the goodies, with less weight.

z-beater

I would disagree. I would say that the weak link is the axles. Also the axles that are provided are a heavier duty moser units. A local friend has blown a few different rear-ends. If you ask him what broke, he will tell you exactly what I stated above. If you fear that the axles are the weakest link you could always cryo-treat the gears. (I am by no means saying that the gears cannot break, just that is not the weakest point.)

I will be running these. I will report when I di so...

Why add weight?