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sierra lsd with drums???
rojabuck - 14/7/03 at 10:30 AM

Would the drum brake assembalies off a 1.8/1.6 sierra couple up with a 7" lsd off an xr4x4??

I ask as although i want an lsd (little improvement in traction) i also want to do some auto-testing so hand-brake skids will be essential and from what i have been told, drums are the way to go when a handbrake is to be given greef

cheers
roja


ChrisW - 14/7/03 at 11:47 AM

The disc shafts fit a non LSD diff so I don't see why it wouldn't work the other way around.

Chris


Fatboy Dave - 14/7/03 at 05:19 PM

I can't see how they would straight off to be honest.

The disc/drum use different drive shaft types. The XR4x4 has bolt on drive shafts with the 'cassette' type Lobro joints, and the 1.6/1.8 have the 'plug in' type Tripode joints.

It's made worse by not being able to cobble a setup together out of an XR and BOTSP regular Sierra subframes.

What you'd either have to do, is find some disc brake rear hubs and drive shafts, or get custom shafts made up with Lobros on one end, and Tripods on the other, or ditch the LSD and go open diff

I can't say I have seen a Lobro type diff/sfats with drum brakes (mind, I haven't looked under any late 'regular' Sarahs, so I may have missed something).

Anyone prove me wrong on this one?


mad-butcher - 14/7/03 at 06:37 PM

I've got the same problem myself at present standard drum brake set up but picked up a cheap lsd and shafts but no carrier disks or calipers I can see the shafts are thicker but can't i just pop the circlip on the lobro and fit the tripod at the drum end or is that to easy
tony


Fatboy Dave - 14/7/03 at 06:41 PM

Tony,

I honestly haven't tried it. I wasn't aware that the CV spider on the plug in shafts actually came off the driveshafts, that's why...

Everything I have built has been disc braked. I doubt it's even worth faffing, as you seem to have the bits that are important. A Granada will provide the rest of the bits you need (but it will have 5 stud drive flanges, unless you swap out Sierra bits).

I think I may have to have a look at this and do a feasability study sometime...


mad-butcher - 14/7/03 at 06:56 PM

thanks the only real reason was my mk indy is built up with drums and this diff came up at the right price the problem is it means changing the uprights on the irs to take a caliper I thought it might be an easy way of picking up the pulse on an electronic speedo using the lobro bolt heads the other alternative on the speedo i beleive is to stick 6 magnets on the tripoid casing
still life would be boring if all went to plan
cheers
tony


Fatboy Dave - 14/7/03 at 07:11 PM

Uh huh. I see. I'm gonna get a set of drum brake shafts and have a play this weekend to see.

As for magnets on the speedo, the best thing we found with Lobro joints is to use the sensor from Merlin on the bolts heads. Six magnets has proven to be too much for most sensors, and the speedo goes jittery at 70, and refuses to go higher (guess how I found out?)

Will update on the shaft tweaking later I think. Sounds like it could be popular...


craig1410 - 14/7/03 at 10:45 PM

"Could be popular"

Count me in!!
I have a diff from a Sierra/Grannie (7.5" type) with shafts, discs and hub carriers but no calipers. I'd rather use the drum braked back end if possible since it will fit inside my 13" wheels and I think(?) the handbrake setup will be easier to install too. I got the diff for free (open diff) with the other stuff so wanted to use it but maybe I'd be better just getting a diff from a drum braked car with all the bits complete. The only problem is that I am using a Rover V8 powerplant so I was worried the torque would bust the diff.

Should the tripode type diff and shafts be up to the job for V8 power? Tyres should be the limiting factor anyway in such a light car.

Cheers,
Craig.


Fatboy Dave - 14/7/03 at 10:58 PM

Hi Craig

Handbrake cable is easy enough for both. Disc back end just has a lever that the cable hooks over. Easy job!

The Granny diff is favourable with the V8, as it's legendary for popping them off (although, as you pointed out, less of a problem with the reduced weight, and the tyres are the weakest link anyway!). The major factor is the ratio. You really want a 3.14 from a diesel (1600 has them too? Dunno, Haynes is downstairs) if you go with the open diff.

As for wheels, well, I'd hope to be going for 15s, rarther than 13s, especially with a V8? The disc backend won't go in a 13 (and IIRC, not in a 14 either).