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lsd man
Julian B - 13/5/03 at 12:09 PM

Can anyone recommend a suitable lsd and rear disk brakes (whole rear sub frame will do) to fit to a rover v8 locost? So in one I’m looking for a lsd that isn't going to cost me too many Lsd... If that makes sense!

Cheers


ChrisW - 13/5/03 at 01:22 PM

Sierra XR4x4?

Chris


ned - 13/5/03 at 02:21 PM

Granada, BMW aswell, though I've gone standard sierra rear discs (later, abs models), no lsd yet.


James - 16/5/03 at 10:20 AM

quote:
Originally posted by Julian B
Can anyone recommend a suitable lsd and rear disk brakes (whole rear sub frame will do) to fit to a rover v8 locost? So in one I’m looking for a lsd that isn't going to cost me too many Lsd... If that makes sense!

Cheers


Are you after an IRS system or live axle?

A 2.8 Capri (if it's Live axle you're after) has LSD I believe.

Also, Hicost is selling a big power capable Chevy axle so try a mail to him.

Cheers,

James


taz - 19/5/03 at 07:41 AM

Doesn't have to be the XR 4x4... The GLS 4x4 has the exact same running gear. In fact the oly differences between the GLS and XR is the trim!


James - 19/5/03 at 10:14 AM

quote:
Originally posted by taz
Doesn't have to be the XR 4x4... The GLS 4x4 has the exact same running gear. In fact the oly differences between the GLS and XR is the trim!


Hmmm, never heard of one of them! Cool- more donors!

James


stephen_gusterson - 19/5/03 at 12:02 PM

quote:
Originally posted by ned
Granada, BMW aswell, though I've gone standard sierra rear discs (later, abs models), no lsd yet.



AFAIK very few granada had limited slip, and in the manual for my 2.4 V6 model it says throughtout the range it was an option.

Its likely to be a diff like the sierra standard one


billy - 22/5/03 at 08:40 PM

oh no............we all need lsd,who wants 1 wheel spinning and going nowhere>????.i dont so go for 4x4 lsd m8.and you ned.lol


Noodle - 23/5/03 at 11:01 AM

According to Des Hamill in "How to Build and Modify Sportscar & Kit Car Suspension and Brakes for Road and Track" <<pauses to take breath>>, a live axled road vehicles doesn't need an LSD. They're often used to mask inherent setup problems.

Wheelspin on take off will usually be on the right-rear because of a torque reaction through the differential effectively lifting the wheel of the ground. An LSD doesn't solve the problem, but reduces it.

By making an adjustable bracket on the o/s only, that twists axle, a bit of setting up should result in boths wheels spinning the same amount.

If however, you're using IRS or you'd like to use that enviable torque to go powersliding for fun (and who wouldn't) that feel free to disregard my ramblings.


Cheers,

Neil.


Stu16v - 24/5/03 at 04:34 PM

I would dare to suggest that Des Hamill hasnt cornered a car hard enough to get an inside rear wheel lifting mid corner as you are trying to get some power down. This doesnt happen (so much) with an LSD. My standard xflow powered Westy would do this when provoked. Also, for the loonys amongst us (i know there wont be many..... ) power tail slides become a bit hit and miss. Not with an LSD..... And finally in the wet, the handling of the car becomes so much more predictable. You can pull away from a junction without lighting the tyres up with just a merest whiff of throttle.

HTH Stu.


Mr G - 26/5/03 at 06:16 PM

quote:
Originally posted by Stu16v
I would dare to suggest that Des Hamill hasnt cornered a car hard enough to get an inside rear wheel lifting mid corner as you are trying to get some power down.



He only lives down the road from me, I'll go and ask him if you like.


Cheers

G


billy - 26/5/03 at 09:14 PM

well as i know des well and have spoken to him alot about racing i can asure you chaps that he has mixed it with some serious peeps on the race side of things,so ill say that perhaps he know what hes talking about (.oh and hes coming round my place this week to give me some needed advice on setting up me kit).........coooooooool


Stu16v - 27/5/03 at 01:13 AM

quote:

He only lives down the road from me, I'll go and ask him if you like.



Yes please. Always willing to expand my knowledge......

quote:

well as i know des well and have spoken to him alot about racing i can asure you chaps that he has mixed it with some serious peeps on the race side of things,so ill say that perhaps he know what hes talking about



Then he has cornered hard enough then....8-0

For 'normal' road use a live axle with a 'free' diff is more than adequate. Get yourself some big HP and/or do a lot of gooning/trackday use and an LSD becomes a handy piece of kit.
But sometimes a poor choice or setup of an LSD can cause more handling problems than they cure. Especially if someone dumps an LSD out of a rally car straight into the back of a Locost.....

[Edited on 27/5/03 by Stu16v]


craig1410 - 27/5/03 at 12:02 PM

Hi,
I have the Des Hamill book too and just wanted to clarify something to prevent everyone rushing off to build one of those adjustable trailing arm linkages as mentioned a few posts back.

Unless I am badly mistaken, they will NOT work for either a de-dion or IRS setup where the diff is part of the chassis. This is because there is no propshaft torque reaction transferred to the wheels on these setups. Only live axle cars can benefit from the adjustable angle trailing arm.

I make this clear because I very nearly started to build it into my design before I had really thought about how it works. Then it dawned on me and I felt really silly. Imagine how silly I'd have felt if I'd built it only to find that it didn't work worth a damn (and my axle would probably have fallen out just to cap it all... )

My opinion on the whole LSD argument is that I'll fit one later if I feel it is necessary. I use a Sierra/Granada diff at present and can swap in an LSD version as required. The non-LSD diff's as plentiful and cost next to nothing so shove one of those in and see what happens is my advice. Use it to optimise your suspension setup before adding an LSD as the icing on the cake later if necessary. If you use the best tyres you can afford and drive in good weather on tarmac then it shouldn't really be necessary, except for the occasional wet roundabout which we all like to go round more than once just for fun...

Cheers,
Craig.


Noodle - 27/5/03 at 08:19 PM

quote:
Unless I am badly mistaken, they will NOT work for either a de-dion or IRS setup where the diff is part of the chassis. This is because there is no propshaft torque reaction transferred to the wheels on these setups. Only live axle cars can benefit from the adjustable angle trailing arm.


Correct, assuming a chassis that can absorb the torque. My original statement referred to a live-axles vehicle. However, for all of that, could this be why Ford offset the Sierra differential? A longer driveshaft will twist more, and the shorter one offers greater restistance, suitable for the o/s wheel. Does this mean they were expecting the diff to be able to squirm in it's mounting?

Interesting. Or not as the case may be.

Neil.


craig1410 - 27/5/03 at 11:58 PM

Noodle,
Yes, I realised from your post that you were aware that it only applied to Live axle cars but I wanted to clarify it for the benefit of anyone who may have not realised this.

As for the offset Sierra diff, I think you are giving Ford too much credit for thought here

The pinion must always be offset wrt the crownwheel by design and if you have equal length driveshafts then the only way to effect this is to have an offset input flange and offset propshaft. This makes the tunnel wider which is generally not desirable. To keep the propshaft in line you need a central diff input shaft and thus unequal length driveshafts.

I don't think that Ford would expect the diff mounts to flex but you never know...

Cheers,
Craig.


Chazzy - 8/6/03 at 03:22 PM

I think the Granada Scorpio (cossie V6) has a LSD as std. I've got one in my stuart taylor. I was what is technicaly known as a "Jammy bugger". My std diff was waiting to have theoil seals changed(cost £40 ish) and a passer by told my friendly mechanic he had a LSD in his garage, It ahd done 11 miles. the casing is a lot beefier. Its also 3.91 :1 as opposed to the 3.64? in the sierra.