Is it the 3.92? i thought that was a 4.42 or something...

[Edited on 14/1/09 by westy turbo]

I think you get a 4.27, been some on ebay recently. They might be 6.5 inch tho if they were on 1300s and stuff.

Hey Miger ! thanks for the info!

I'm sure 3.92 is the lowest 7" commonly available - although I believe quaife or someone make a 4.44 or something like it for a few grand!

If you go to 7.5" you can get lower ratios like 4.42 I believe.

Cheers

mark

So the 7.5 is a straight swap?

The case is altogether bigger although you could mod your chassis to fit one.

You might be able to make up some hybrid shafts as I'm not sure the flanges are the same.

I know some sierras use the 7.5" diff and I understand people have used them in Indys etc

7.5" has a bigger/wider casing (has a different rear beam when fitted to the sierra)


the 4.09 and 4.27 ratio 7.5" diffs are found in 2.0 8v and 16v scorpio's (the ugly bug-eye ones 95-98) these have 100mm bolt-on CV's (the same as the 4x4 sierra's etc)
but the shaft lengths might be different :?


this lot make 3.14, 4.1, 4.44 and 4.7 ratio's for 7" click
raceline sell them: click


[Edited on 14/1/09 by mcerd1]

http://cgi.ebay.co.uk/ford-sierra-rear-diff-4-27-1-rare_W0QQitemZ180317213838QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item18031721383 8&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A13|39%3A1|240%3A1318

looking at that it looks like a 7.5 inch case.

sorry

Thank you all for your help!

just to second post about raceline (they are not the only suppliers, SBD used to do them too)

many alternative 7" sierra CWP's are available, just depends on your budget as they ain't std ford ones!

PS if you have an LET how can you use much over a 3.9:1 anyway????????????????????????????

We have an RWD opel kadett with LET making around 375hp and in that car which weighs around 800kg with 3.4:1 diff and it still lights up yokohama A048R tyres instantly in every gear no matter how gentle you try to be......we're currently trying to map some boost progression into it using a proper ECU instead of the Bosch Motronic!

For mine i have a 3.62 and a 3.92 will be on MBE 967E and a AVCR will do the rest,the diff that was asking is for my friends 3door sierra cossie,that sees quite often some drift events

Unless it's been changed at some point, a 2WD cossie has a 7.5" diff anyway. With the larger CV joint flanges, too.

Liam

Didnt know that thanks..

if my memory serves right the 7.5 diff in the granarder are not LSD as the cars had T,C in stead i nearly got cort out my sen but i checked it befor handing over my cash . some pepole are t**ts
a good 2WD 7.5LSD from a cosworth will be about £350 ish

quote:

---

Originally posted by westy turbo
Didnt know that thanks..

---

Kinda confused now...so was been in a granade as 7.5 non lsd and in cossie 2wd 7.5 with lsd?

Yeah most grandads have 7.5" non LSD. Only the pre-bugeye 24V cossies have a 7.5" LSD, but then that has standard sized 100mm diameter flanges/CVs. Your mates 2WD cossie sierra has 7.5" LSD with 108mm flanges/CVs and big fat shafts.

Liam

Cheers Liam

any clue what a 4.44.1 crown pinion on a 7" diff top end speed will be?

quote:

---

Originally posted by westy turbo
any clue what a 4.44.1 crown pinion on a 7" diff top end speed will be?

---

Thanks but doesnt work...