Sierra diffs in Old School Fords

[Streetfighter]

As per the title really, are there many OSFs running Sierra diffs? I'm starting to get some decent power through my Cortina and I want something a bit special at the rear end. Ideally ford stud pattern. Before anyone says Atlas, they're ludicrous money nowadays and if I've got to get things shortened and so on an IRS just makes nose sense to me, rightly or wrongly!

 

I've heard tales of 4X4 front hubs, custom cradles and shortened driveshafts, but any solid info is greatly appreciated.

[eeb43]

have a look at scimitar se5 axles its a salisbury 4 ha so will take xjs lsd and a good range of diff ratios 

sierra is good but it will be alot of work to keep it irs or make a unit to take all the sierra bits i know ive done it!

[Streetfighter]

What did you fit the Sierra gear into? Did you have to do any width narrowing? I'm thinking of a 4X4 LSD, making a cradle and having control arms made up that'll incorporate mounts for my rear coilovers. I'm guessing the shafts and diff will handle 300+ boosted BHP.

 

 

[eeb43]

i made a tubular frame to take diff with fixed bearing carriers basically a frame to take all the moving bits so a live axle in effect i shortened the shafts by cutting and welding them and put 5mm wall cds over them and welded that on although short shafts are available

[Streetfighter]

Oh, so you used the standard Sierra lower arms/hub retainer and just used the cradle  to locate the 2 bushes?

 

That'd make life lots easier, thinking about it.

[eeb43]

1. no! lol i have got a jig set up to put mounts on kitcar chassis to use a sierra axle
2. on the live version i didnt use the tube or wishbones i made it all if i get chance tomorrow i will take some pics

[Streetfighter]

Ah, I see. I read that wrong then!

If you could get some photos that'd be great, only photos I can find are of McRae's IRS MK2 Scrote and even then the photos are pretty gash!

[eeb43]

[mk1del]

That looks like a lot of fabrication work

[eeb43]

16 minutes ago, mk1del said:

That looks like a lot of fabrication work

not now the jig is made! lol

 

[Streetfighter]

I see what you mean now about it being like a solid rear, I didn't think about that type of setup but that's very clever..

[colr6]

Seems like a lot of work to me when at the end of it your still on a solid axle. Thought the idea of using the Sierra diff and shafts was to end up with a economical IRS ??

[eeb43]

11 hours ago, colr6 said:

Seems like a lot of work to me when at the end of it your still on a solid axle. Thought the idea of using the Sierra diff and shafts was to end up with a economical IRS ??

the irs in its standard form is ok but its a set width i can do that narrower and put it on leaf springs or 4 bar i have also been playing with wishbones in a similar set up to scimitar ss1 as well as tiger 7 style 

[colr6]

It's on this like this where access to breakers yards would prove invaluable to study various installs on factory cars. You could study the fitments and use different parts with the view of hopefully coming up with a solution that Joe blogs with a bit of fab knowledge and a welder could fabricate at home. Health and safety in breakers yards has a lot to answer for !! There is an install over on BSC that a guy did but would suspect it's a little bit out the reach of the normal  diyer, it's a work of art tbh but a bit specialised.

[eeb43]

i have got a few sierra/granada sxles and i turned  sierra on its roof and made a jig from the mounts on that to use a whole sierra irs in a kitcar

also got a strange kitcar axle from a racecar i believe using sierra bits but with the ndiff mounted in the body and everything else on a tube

[Streetfighter]

I think the hardest part would be having the control arms move without hitting the chassis rail on full compression. That said I'm running 200lb × 14" coilover springs so I doubt that'd happen. Can pick up an entire Sierra Bosworth rear subframe for less than a standard Atlas axle so any fabrication work would be worth it.

[khanlad]

What are you running in your car? Im running a turbo cossie, putting a bit over 300 through my english, quiaffe atb and 3j shafts,  it gets abuse, i dont drop the clutch out of every junction, but i do when i know people are looking wondering how sideways it will go!  I sold a diff, beam, trailing arms and shafts earlier in the year, think it went for about 550? It looks like a hell of a lot of work to save 300 odd quid? 

[Streetfighter]

Running 350 on a Nissan CA18DET.. Nobody has been able to give a straight answer on how tough these 3J and so on shafts are. I'd rather break some drive shafts than hundreds of pounds worth of halfshafts. Car gets given a very hard time all the time.

[eeb43]

4 hours ago, khanlad said:

What are you running in your car? Im running a turbo cossie, putting a bit over 300 through my english, quiaffe atb and 3j shafts,  it gets abuse, i dont drop the clutch out of every junction, but i do when i know people are looking wondering how sideways it will go!  I sold a diff, beam, trailing arms and shafts earlier in the year, think it went for about 550? It looks like a hell of a lot of work to save 300 odd quid? 

i have got about a dozen slipper sierra diffs at least 50 pairs of shafts and probably 75 open diffs of various ratios so its just a couple of days fabrication work and about £60 of steel

[khanlad]

39 minutes ago, eeb43 said:

i have got about a dozen slipper sierra diffs at least 50 pairs of shafts and probably 75 open diffs of various ratios so its just a couple of days fabrication work and about £60 of steel

If you have that many laying around you could sell him one cheap to get him started then?

[eeb43]

12 hours ago, khanlad said:

If you have that many laying around you could sell him one cheap to get him started then?

no one ever wants to sell me them cheap