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General Car Related Discussion.To discuss anything that is related to cars and automotive technology that doesnt naturally fit into another forum catagory.
Don't forget there is 2 output flange sizes on the diffs the 2wd cosworth is 108mm and the 4wd cosworth and other non cosworth sierras are 100mm, do you know what your rear axle was off?
Arrow shows where the difference is on the diff, you can cut the bracket off and make a new one to weld on, some people have cut the diff down to size.
Failing that you'll need a 7.5 inch beam, the stub shafts on the trailing arms are also different on 2WD Cosworth with the 108mm joints.
You might be able to swap the output shafts on the diff and keep your original setup, but I've never tried this, although I'm sure someone on here will know if that will work !
Yea thanks very much, I’ve been working on this car for a while! Really need to get it finished, as you say I can cut the diff or the beam to get the diff to fit, will suck it and see regarding the rest although I have a feeling it should be ok.
Just get a rear subframe from a Granada mk3. They all had the 7.5” diff, except for the Granada 2.9 4x4, which had the 7” diff just like the Sapphire Cosworth 4x4.
But first check what size diff you have now, it might already be 7.5”.
Last edited by Marc sierra; 27-08-2018 at 09:31 PM.
Yea had lots of work done to it by Rick Wood Racing, this is why Ive fitted a Cosworth drive train but to complete it I need a 2wd Cosworth box with LSD,
Looks super clean and will be a fast car once you sort out your drivetrain properly. Have you asked Rick Wood Racing for their advice as they are the Essex v6 experts?
How much does one of those Ric wood Essex v6s cost ?
looks like an interesting car, where does the 300 bhp number come from? Has it got a supercharger or turbo charger fitted as there is zero chance of a v6 Essex making that sort of power.
Arrow shows where the difference is on the diff, you can cut the bracket off and make a new one to weld on, some people have cut the diff down to size.
Failing that you'll need a 7.5 inch beam, the stub shafts on the trailing arms are also different on 2WD Cosworth with the 108mm joints.
You might be able to swap the output shafts on the diff and keep your original setup, but I've never tried this, although I'm sure someone on here will know if that will work !
iirc the output flange shafts differ in length between lsd and non lsd diffs so you would need the 100mm output shafts from an lsd diff to swap over into the 2wd diff
looks like an interesting car, where does the 300 bhp number come from? Has it got a supercharger or turbo charger fitted as there is zero chance of a v6 Essex making that sort of power.
I have my doubts too. We can only get 180bhp from a lancia 2.8 V6 which included 6 jenvey throttle bodies on omex. Custom cam and Simpson race exhaust.
I don't have any experience with the Essex V6 myself but if he's actually using custom cylinder heads I don't see why not.. it even says around 100 bhp/liter capability for those heads, and I can definitely see that happening when you wind it up to say 7krpm or more, as MarkV8 also said earlier here:
Originally Posted by Mark V8
To get anywhere near that power at the wheels out of the Essex V6 it must be very highly strung!
I think that's actually why he has some trouble off the line, combined with the higher first gear of the T5 that makes perfect sense. Will be interesting to see how this all plays out and how the car is performing in the end, curious for the results
daiboy, as Marc (with a 'c' this time, haha) said absolutely check what you have in there NOW before we can give you any further advice here. You will also save yourself a lot of headaches if sth turns out to be different than from what we all were thinking and may save you from getting parts that end up not fitting your setup!
Originally Posted by Marc sierra
But first check what size diff you have now, it might already be 7.5”.
Originally Posted by Marc sierra
Just get a rear subframe from a Granada mk3. They all had the 7.5” diff, except for the Granada 2.9 4x4, which had the 7” diff just like the Sapphire Cosworth 4x4.
Is it just the 2.9 4x4? Not sure but I thought the Scorpio Mk1 ("Granada Mk3") also came with other 4x4 engines and I would guess they are all using the 7" rear diff.
Originally Posted by Mark V8
Arrow shows where the difference is on the diff, you can cut the bracket off and make a new one to weld on, some people have cut the diff down to size.
Failing that you'll need a 7.5 inch beam, the stub shafts on the trailing arms are also different on 2WD Cosworth with the 108mm joints.
You might be able to swap the output shafts on the diff and keep your original setup, but I've never tried this, although I'm sure someone on here will know if that will work !
One more Q for Mark: I didn't know that was all that is required, cutting where the arrow is to get a 7.5" diff fitted into a 7" rear beam?!
Good point on the shafts though.. length (LSD or open diff) and interface (bolted or push-in type) as well as maybe the flange (100mm vs. 108mm of the Cossie).
One more Q for Mark: I didn't know that was all that is required, cutting where the arrow is to get a 7.5" diff fitted into a 7" rear beam?!
Good point on the shafts though.. length (LSD or open diff) and interface (bolted or push-in type) as well as maybe the flange (100mm vs. 108mm of the Cossie).
You can cut the diff or remove the bracket completely from the beam and fabricate another one, I did the later but have no pics, the diff casting is also a bit bigger near the front and will need clearance added.
[QUOTE=janus;6779409 Is it just the 2.9 4x4? Not sure but I thought the Scorpio Mk1 ("Granada Mk3") also came with other 4x4 engines and I would guess they are all using the 7" rear diff.
[/QUOTE]
There was also a 2.8 4x4, before the 2.9 was introduced. But there were no Granada mk3 4x4s other than those.
You can cut the diff or remove the bracket completely from the beam and fabricate another one, I did the later but have no pics, the diff casting is also a bit bigger near the front and will need clearance added.
thanks very much for your guidance, not decided which way to go yet but at least I know its possible.
Not it sure why people thing you cant get the sort of power Im quoting from the Essex V6, Rick Wood takes them up to 400 bhp, I did post his web page infor that explains this far better than I could, never mind I know what power I have and just need to sort this gearbox then, hopefully Ill have takeoff at the lower and higher levels. Thanks again.
daiboy, at least for me your blob: image links here are not working so I can't see what you are posting there.
Mark & Marc, thanks for your infos! So for fitting a 7.5" diff into a 7" beam, the way I understand it it's possible by just some trimming to those two mounting sections and the rest fits without problems (no trimming on housing otherwise, same shafts and interfaces etc)?
Thanks very much for all the responses, I managed to get a 7.5” beam for the XR6 so that will sort out my initial problem of fitting my Cosworth Diff to a 7” beam.
Onwards and upwards, not sure why my pics are not showing, will be something I’m doing wrong I suspect.
shafts are different mate - 2wd 108mm and 4x4 100mm
oh good point. and one last clarification:
7" with 100mm would typically be any OHC/DOHC Sierra, maybe also V6, and the 4x4 Sierra incl. Cosworth. How about the Granada Mk3/Scorpio Diffs?
7.5" comes in 100mm variant from Granada Mk3/Scorpio and the 108mm for all the 2wd Cosworth Sierras?
Thanks
Yes that’s all good. I now have a 7.5 Beam and a 2wd Cosworth Diff so I’m not anticipating any issues. I also have drive shafts 108 mm as per the Cosworth. I’ve already got Cosworth breaks on the back. Many thanks for all you guidance.
27-08-2018 | 07:16 PM
So for fitting a 7.5" diff into a 7" beam, the way I understand it it's possible by just some trimming to those two mounting sections and the rest fits without problems (no trimming on housing otherwise, same shafts and interfaces etc)?
