torsen limited slip differential or..
Moderator: martauto
how would an z3 torsen limited slip differential 3,15 be to drive on a m20b25?
http://allegro.pl/dyfer-szpera-bmw-z3-3 ... 61207.html
what would you rather have an used torsen or an fully rebuild normal lsd ? and which would be somewhere in the middle of fun driving and motorways 3.64 3.73 3.91 ? or i can choose to have anyother ratio
http://allegro.pl/szpera-bmw-e30-duzy-d ... 30366.html
my friend is going to poland and is going to bring me one of these which one should i choose? and which ratio and whats the 1.5 WAY , 2 WAY all about?
http://allegro.pl/dyfer-szpera-bmw-z3-3 ... 61207.html
what would you rather have an used torsen or an fully rebuild normal lsd ? and which would be somewhere in the middle of fun driving and motorways 3.64 3.73 3.91 ? or i can choose to have anyother ratio
http://allegro.pl/szpera-bmw-e30-duzy-d ... 30366.html
my friend is going to poland and is going to bring me one of these which one should i choose? and which ratio and whats the 1.5 WAY , 2 WAY all about?
Last edited by BMWE30325 on Mon May 21, 2012 9:57 pm, edited 4 times in total.
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Grrrmachine
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It would make it very very sluggish. The lowest ratio diff fitted to the 325i was a 3.64, and some people have tried fitting the 3.45 ratio from the diesel E30s and reported a significant drop in acceleration. Going all the way down to 3.15 will make the car pull away like a bus.
4.1 would make a 325i very lively...
4.1 would make a 325i very lively...
'89 325i Touring | Touring Resto Thread | In-Dash Screen install
so which one is somewhere in the middle?Grrrmachine wrote:It would make it very very sluggish. The lowest ratio diff fitted to the 325i was a 3.64, and some people have tried fitting the 3.45 ratio from the diesel E30s and reported a significant drop in acceleration. Going all the way down to 3.15 will make the car pull away like a bus.
4.1 would make a 325i very lively...
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Grrrmachine
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3.64 for cruising, 3.91 for acceleration, 3.73 for a compromise.
'89 325i Touring | Touring Resto Thread | In-Dash Screen install
ok thanks for the info i'll think the 3.91 would be good as i dont use the car to often on motorwaysGrrrmachine wrote:3.64 for cruising, 3.91 for acceleration, 3.73 for a compromise.
- Brianmoooore
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3.15 torsen diff. needs to be used with a direct fifth gear box, such as that from an E34/36, preferably left attached to a 2.5 or 2.8 M50/52 from the same car.
so it would be ideal for an m52 conversion with the e36 gearbox?Brianmoooore wrote:3.15 torsen diff. needs to be used with a direct fifth gear box, such as that from an E34/36, preferably left attached to a 2.5 or 2.8 M50/52 from the same car.
- gooseygander110
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3.91 is awesome fun !!!! probably crap on motorways...... awesome for grin factor though !!!
LOL!Brianmoooore wrote:3.15 torsen diff. needs to be used with a direct fifth gear box, such as that from an E34/36, preferably left attached to a 2.5 or 2.8 M50/52 from the same car.
Weren't the facelift "sports" fitted with a 3.91. Was the 5th gear ratio on the sport gearbox the same as a standard 2.5? Get a good gain in acceleration
- Brianmoooore
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A 3.15 on an E34/36 box is the equivalent of a 3.89 on an E30 box, so will be a 'sport' ratio, rather than an 'economy' one - somewhere between the 3.76 and the 3.91.
And 3.91 on 325i tourings and tech 2 sports.BMWE30325 wrote:are these the ratios that where originally fitted to 325?Simon13 wrote:a correct 325 ratio. I'd be looking for a 3.73 or 3.64
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Grrrmachine
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'89 325i Touring | Touring Resto Thread | In-Dash Screen install
- Brianmoooore
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Fully agree! One of the best mods. I ever did to my red touring.Ziggy wrote:3.73 is nice on a 2.5. Just that bit less buzzy than a 3.91 without blunting things too much.
I ran a 2.97 on my 320i for a while to see what it was like,
Nice on the motorway flying along with hardly any revs on. Foot on the floor for any kind of incline though.
No real acceleration to speak of in the lower gears, and huuuuuge gaps between the gears. Makes for a very lazy driving style.
Nice on the motorway flying along with hardly any revs on. Foot on the floor for any kind of incline though.
No real acceleration to speak of in the lower gears, and huuuuuge gaps between the gears. Makes for a very lazy driving style.
1, 1.5, 2 way denotation refers to the direction in which the diff will actuate.
1 way, the diff will only lock when accelarating
2 way, the diff will lock with the same force when accelarating as with engine braking
1.5 way the diff has 2 separate pre determined lock ratings. Most likely a greater lock (shallow ramp angle) on accelaration, and a lower lock on engine braking.
Torsen, irrespective of the ratio is a torque sensing setup driven intirely by gears. It requires torque input to determine where to deliver torque. Not so good on loose ground where lack of grip lowers the torque sensing aspect, ideal on the road though..
1 way, the diff will only lock when accelarating
2 way, the diff will lock with the same force when accelarating as with engine braking
1.5 way the diff has 2 separate pre determined lock ratings. Most likely a greater lock (shallow ramp angle) on accelaration, and a lower lock on engine braking.
Torsen, irrespective of the ratio is a torque sensing setup driven intirely by gears. It requires torque input to determine where to deliver torque. Not so good on loose ground where lack of grip lowers the torque sensing aspect, ideal on the road though..






