Quick reply needed about dif/max speed.
 

Hi guys! found a smashing deal on ebay for a lsd 7.5inch diff thats local to me. Only problem its a 3.64 rather than a 3.9. The Diff tag reads 91 GG ADA 3.64 its fron a granny cossworth im pretty sure its a lsd and has 100mm flanges.

16's with 55wall, 3.32, 1.9, 1.31, 1.0 and .838. Final drive is 3.64
6400 redline
1st/37.8mph
2nd/66.1,
3rd/95.9,
4th/125.6,
5th/149.9

Would normaly be this in donor car
17's with 55wall, 3.32, 1.9, 1.31, 1.0 and .838. Final drive is 4.1
6400
1st/34.9
2nd/61.0
3rd/88.5
4th/116.0
5th/138.4

I think thats kinda insane as thats pretty fast top end but not good on acceleration? would rather it the other way around really as acceleration does not get you speeding tickets.

Is that just computed speed or taking into account drag?

Acceleration is gr8 so long as you can put it on the ground, with all the power and light weight you may find 1st gear to be unusable.

I am using a 3.64 behind a 150BHP V6.

TT

Ps. the 7.5" LSD should be between £200-£250 normally. with 7"'s about £80 less...

TT

Two things,the higher the number of the diff ratio the more acceleration ie 4:1/5:1, the lower more top end less quick acceleration and in any case the car weighs many times less than the old Granny but then factor in the aerodynamics of of a 600kg brick and you will have you top speed.

you will get to 60mph quicker than most exoctics costing £100,000 and more for a lot less money and much more fun. :D

Edit: as TT says getting it on the ground is the problem with such a light car.

true true just have to add the weight of a 2.5l turbo straight as well. Putting that power down is going to be trouble on the iva i know it! 260bhp+ rofl insane.

Great in that case i guess lower is probably better. I have just done something stupid.......... :D

ford scorpio cosworth complete rear axle diff etc.....£100!!!!!!!!!! umm i hope i can use it? Maby i was a bit brash but i thought the scorpio has the same drive shafts as the sierra? Dont have a clue what ratio it is of if its lsd but its from a cossy so cant be that bad..... at the very least i have the dif i want and can probably use the discs calipers ect.

If there is no tag just divide the pinion by the crown wheel teeth and this is the ratio to 1.

It's a scorpio one not a Granada one so it will be 3.64 open not LSD.

Track is slightly wider on the scorpio too so the shafts may be longer.

TT

Hubs are 4 stud though which is better than the 5 stud Granny ones.

TT

Nice will get it through the iva at least. Will have to send the shafts off to get shortened i guess but still good buy i think. Yeah the 4stud helps as it matches the sierra uprights. Shame about the shaft length but hay for 100quid cant grumble :D gives me everything i need to get on at least.

well the diff will sell on for £60, and the rear calipers,hubs and carrirers for £60+ too.

TT

The rear calipers,hubs and carrirers ect can be used and are the same as the sierra ones i presume? or have i just gone and bought completely the wrong thing? hah

Should fit fine, they are slightly different but it should not make any difference.

They will be vented disk which was only ever the case on the 4x4 Cosworth Sierras.

TT

Scorpio and Cosworth 4x4 use same rear disks.

TT

Got the original diff i found as well as listed as ford 7.5inch lsd. For £120 but did a offer for £100 that was accepted and its in Poole so only 15min drive. Think that is a ok price or should i have haggled a bit more?
Add text@
"1992 GRANADA 7.5"LSD GOOD WORKING CONDITION WAS BEING USED UNTIL RECENTLY WHEN FAILED MOT
DIFF TAG READS 91 GG ADA 3.64"

checking on locostbuilders found this

soooo got the right diff and can use all the rest of the stuff. Fantastic :D
thanks everyone for advice!

£120!!! You Lucky B£$%^£$

TT

Buy it now was 120.. i made a offer for 100 that was accepted.

Right picked up the diff. It is a lsd and its fantastic! but huge heh :rolleyes:
Just had a look at the brackets and well think im going to have to make the top a bit wider. What do you guys think?
Also the guy have a few more so if anyone wants his number give me a msg and i will forward it to you.

Well in sierra lands theres 3 ways.

1) Swap to 7.5" Beam
2) cut the lug on the diff down.
3) cut and shut the top mount on the beam.


1) is out, 2) devalues the diff

so I recon you cut and shut the mounting dracket and make it a bit wider ;)


TT

indeed was thinking of getting another plate and widening it a bit for the top. Will take measurements ect and make a new threat about it. As i belive it would be quite handy for people to know. I really dont want to have to cut into the diff :D

:eek: no nead for threats!!!

TT

rofl typo "thread"