Kerazy S-Pak

Hi everyone, Ive been wanting to upgrade the diff on my 93 ED Fairmont from 3.08 to 3.27 and Im wondering how much higher the car will rev at any given speed. Ive got a family friend who will charge me $250 for the diff and installation/labour, does that sound like a good price? I was pretty impressed with the offer.
Does it matter that the diff is not LSD? Im afraid the shorter ratios will burn up my tyres oldskool, I want the car to launch hard, not rip mad burnouts! :)

Brent79

Um...whats wrong with the 3.08? I'll take yer old one if u change it! :)

Brent

PHoeNiX_EB

go get an old 4.11 ford 9 inch diff and use that :)

RAPTOR

It will rev this much harder, simple maths;

((3.27-3.08)/3.08)x100 = 6.168%

Yep, that's right a bit over 6%, not exactly revving it's head off.

OR (3.27/3.08)x(old revs) = new revs

So for a given speed, instead of say 2000rpm it'll be doing 2123rpm.

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madEAs

I have just gone from a 3.23 to a 3.08, not by choice, but i believe will keep crusing speed down a little, considering im using the proper ea 5spd box with the higher 1st gear ratio and a little higher 5th ratio. What box is the diff going to be behind? 5spd or one of the autos?

ChuBBz

let me get this straight...
you wanna upgrade your single spinner to another single spinner????
mate, get yourself an LSD diff (3.45:1)
with good tyres you will be taking off much harder...

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Kerazy S-Pak

Thanx for the info RAPTOR. :) Its a negligible increase to say the least.
My ED is an auto MadEAs...It revs amazingly low at high speeds (compared to my old EA 3 spd)
Chubbz LSDs seem to be really expensive and not $ feasible atm for me, but would you recommend an LSD regardless of the ratio? Ive always been under the impression anything above 3.23/7, 3.45 was LSD cos short ratio=spinning tyres and not goin anywhere. My diff is noisy atm (bearings) and I need to fix the problem, either by fixing thecurrent diff, or getting the single spinner 3.27.
Ive never driven an LSD equipped car and dont know what all the advantages of having an LSD are.

SiX_iN_a_RoW

Theyre fun in the wet

Biggest advantage is being able to get the power to thr road better on take off....other than that like I said theyre fun in the wet around corners as you get both wheels happening....

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Lets go find that Hotdog tree I planted

Lowered EF Futura
Black Steelies ( too cheap to buy proper mags )

madEAs

if you went from a 3spd to a 4spd u would have noticed the world of difference, if you need to get the diff fixed and you know the 3.27 is in good condition well then go the swap, i dont know how much a reco for a diff goes for. you will also need to change your speedo sender gear, so your speedo wont be off.

I used to consider lsd as a primitive form of traction control, and i suppose it is. It is well worth it, but they are a lot more expensive.