Best Diff To Use?

[Guest ScotMac]

Sh*t...lost the bid. Oh well, gives me more time to research it....Here is a good thread on it:

http://community.rhocar.org/index.php?show...t=0entry65500

[Grim]

i sometimes wish i didn't have an LSD...

[Guest ScotMac]

Great Grim. I can get you a non-LSD, and we can do a swap!!! Just let me know...

[Longboarder]

Thats interesting Grim. What is the downside of having and LSD in the car?

 

Nigel

[Guest salty_monk]

I would guess it makes it easier to spin it if you get out of shape but other than that I can't think of any drawbacks....

 

Personally I preferred the 3.92 diff over the 3.62, not tried an LSD. Obviously if your engine has the power to drive the 3.62 then it shouldn't be a problem, mine was dyno'd at 100BHP at the wheels. The 3.62 made it less keen to rev & cut top speed & acceleration through the gears. Bob Tucker told me he found the same thing with 116 BHP (I think) at the wheels (although the 3.62 was mildly quicker at Santa Pod on the quarter maybe 0.1 of a second or something I think). Obviously if you have a much more powerful engine then the 3.62 will be fine & will make the gears longer which will probably be a benefit on first....

 

This subject seems to go on & on & on & on & on...... It's quite personal so I would say try them, they are not hard to fit & the non LSD can be found cheap enough + if you try the LSD & don't like it you're unlikely to lose money on it... just re-sell it...

 

Dan

[Grim]

Thats interesting Grim. What is the downside of having and LSD in the car?

 

Nigel

ending up backwards up an embankment near shrewsbury at about midnight last night.

 

was doing about 70 in third, rears lit up, pointed me towards the central reservation, i overcorrected and span off. OK, it's my fault / inexperiance, but i wasn't expecting a standard pinto to give wheelspin at that speed in a straight line.

Of course, with a standard diff, i'd only have got wheelspin in 1 wheel, and i'd have been able to keep it in a straight line.

[Longboarder]

OK, think I will put the LSD a little further down the list of desirable mods.

 

Nigel

[Guest ScotMac]

Not sure i understand (could be the british "english"! ;-). So, u spun both rear wheels? Why? You hit an oil slick? Accelerating in straight line at 70? kph?

 

Sorry, just trying to understand how the LSD negatively affected the condition, not criticing ur driving. ;-)

 

Thanks, -sm

[Guest salty_monk]

If you have an LSD you won't spin one wheel, you'll spin both thus taking more force to do it & improving traction although if they do go then a spin can be harder to control...

 

I too wondered how he managed to spin the wheels at 70 in straight line with a standard pinto, my modified one wouldn't have done it even in the wet...

 

We use MPH in Britain too not kilometres, roads are still measured in miles too

[Grim]

As salty monk says, with an lsd, when one wheel looses grip, load is transferred to the other wheel. If the other wheel has lots of grip, great, you go faster. However, if the other wheel is close the the edge of traction, the extra load applied to it will cause it to spin as well.

A spinning wheel can't take any lateral grip, which is why it tends to slide. A normal diff with one spinning wheel and one unloaded wheel will be able to take some sideways load through the non spinning wheel, and you're less likely to spin.

 

Yes, 70 MPH, which is about 110kph. I've no real idea why or how it span the wheels at that speed. It was slighty wet underfoot though. It could have been oil, i didn't notice, as i was too busy aiming for something soft. I've also no idea what caused the rear end to step out, perhaps a bump or something.

 

Don't worry about criticising my driving, it aint that great!

[Guest micky bigthumbs]

Noticed that saturday morning,,,,,,,,,,,not the driving the back end of the car comming around alot.... glad your ok though

 

Mick

[Guest micky bigthumbs]

Just a thaught Grim...you bought the car built and the previous owner took the cossie out...did he put heavy oil or ive herd of people putting saw dust in noisey diffs just to sell the car..when it gets hot on long jurneys the diff could be partially locking up ...worth checking

 

Mick

[Bob Tucker]

An LSD also needs really sticky tyres to perform well

(I guess that means safely too?)

[Guest salty_monk]

Yes especially as the Sierra is so much heavier than the 2b... has to effect the characteristics of the diff... Local guy near us in Orpington reckons the Viscous LSD is not very good & the Quaife type (although he doesn't like Quaife but another couple of makes that work the same way) is much better... he quoted me £200 for a 3.9 one built into my casing with new bearings & seals...

 

Dan

[Grim]

i only got the back end out once on saturday... well, ok twice, but you didn't see the first (was extremely slight ). I probably ought to be a little more careful in the car - prior to welding up my chassis, my speed was mostly determined by how much i wanted to get shaken around, which is no longer a problem!

 

How could i check the oil inside? take the filler off and syphon some out?

 

I had noticed the other day that something is leaking on the diff end of the driveshaft, as there's a spray of something sticky on the underside of the car. I don't think this is a failed boot because it looked entirely intact. How far across can the diff oil get with the lsd, and could a low oil level affect it's operation?