3.73lsd diff
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novakiller
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what is a 3.73 lsd diff worth allso what is an m3 diff worth? any help apreciated!
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Karan
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hmmm guessing thse are the ones on ebay.....
both between Ԛ£250-Ԛ£300
3.73 diff is rare, m3 diff is 3.25 ratio
both between Ԛ£250-Ԛ£300
3.73 diff is rare, m3 diff is 3.25 ratio
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novakiller
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yeah thinkin of gettin 1, what would be the best lsd 4 a sport mine has a 3.91 would a 3.71 or 3.25 be better?
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Karan
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3.25 will be shit..... u need a 3.73....
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novakiller
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is that much better than a 3.91 lsd if so why?
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Karan
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slightly more comfortable for motorway cruising....
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Chaos
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the higher the number the lower the gearing basically m8
3.25 will give loadsa mpg but poor acceleration
3.91 (standard on phase 2 sports) gives good accel but more engine noise on m/way and worse mpg
3.64 standard 325i diff ratio - ok accel, good mpg, quiter (cos of lower revs)
3.73 - rare - a nice compromise between 3.64 and 3.91
personally unless i had a really loud exhaust id prob go for a 3.91 i think if buying one.
Its all down to personal preferences really - do u want performance, mpg or a balance
3.25 will give loadsa mpg but poor acceleration
3.91 (standard on phase 2 sports) gives good accel but more engine noise on m/way and worse mpg
3.64 standard 325i diff ratio - ok accel, good mpg, quiter (cos of lower revs)
3.73 - rare - a nice compromise between 3.64 and 3.91
personally unless i had a really loud exhaust id prob go for a 3.91 i think if buying one.
Its all down to personal preferences really - do u want performance, mpg or a balance
Chaos
causing havoc and mayhem wherever i go

causing havoc and mayhem wherever i go
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Rearwheel_nick
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i had a 3.91 lsd when i first got my car and its really fun for just bursts of acceleration always forcing you back into your seat makin the most of the meagre 170bhp or whatever. now thats gone and i have a welded up 3.46:1 diff. which feels very different definately a noticeable change in acceleration at cruising speeds its much more pleasant to look at the econo-gauge.
and i can go over 60mph in 2nd now. personally though id go somewhere between the 3.91 and 3.46 for best of both worlds.
and i can go over 60mph in 2nd now. personally though id go somewhere between the 3.91 and 3.46 for best of both worlds.
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Karan
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hows ure welded diff dude?Rearwheel_nick wrote:i had a 3.91 lsd when i first got my car and its really fun for just bursts of acceleration always forcing you back into your seat makin the most of the meagre 170bhp or whatever. now thats gone and i have a welded up 3.46:1 diff. which feels very different definately a noticeable change in acceleration at cruising speeds its much more pleasant to look at the econo-gauge.
and i can go over 60mph in 2nd now. personally though id go somewhere between the 3.91 and 3.46 for best of both worlds.
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Rearwheel_nick
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hahah funnily awesome. when i have cash id like to swap to a 2way lsd or at least 75% lock uprated bmw lsd. but for a cheap thing welded diff cannot be beaten i love it. only reason i would leave welded diff behind is because id like to do track days as well as drifting.
for drifting though which i guess is why your askin karan, its fapping awesome. although i kept forgettin i had a welded diff when i did a practice day a week or 2 back and couldnt understand the massive understeer if i entered a corner wrong. i have no problems with it as an everyday thing either:) love it really recomend it highly.
for drifting though which i guess is why your askin karan, its fapping awesome. although i kept forgettin i had a welded diff when i did a practice day a week or 2 back and couldnt understand the massive understeer if i entered a corner wrong. i have no problems with it as an everyday thing either:) love it really recomend it highly.
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Karan
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ill be getting me a 3.73 to weld up then!Rearwheel_nick wrote:hahah funnily awesome. when i have cash id like to swap to a 2way lsd or at least 75% lock uprated bmw lsd. but for a cheap thing welded diff cannot be beaten i love it. only reason i would leave welded diff behind is because id like to do track days as well as drifting.
for drifting though which i guess is why your askin karan, its fapping awesome. although i kept forgettin i had a welded diff when i did a practice day a week or 2 back and couldnt understand the massive understeer if i entered a corner wrong. i have no problems with it as an everyday thing either:) love it really recomend it highly.
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M3Compact
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Mad in the head bone.welded diff
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Karan
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simon do u still have that super diff u had lying round? was it 2 way? and what ratio was it? i remember u wanted Ԛ£400 for it-im interested mid july....M3Compact wrote:Mad in the head bone.welded diff![]()
im after a 2 way quite high % lockup one.....
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M3Compact
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I've still got it, buy I'm building Jimbob's 4.1 in to it for a spare. (Currently got 4.45 installed.)Karan wrote:
simon do u still have that super diff u had lying round? was it 2 way? and what ratio was it? i remember u wanted Ԛ£400 for it-im interested mid july....
im after a 2 way quite high % lockup one.....
They're 2 way as standard, any amount of increased locking can be achieved in either direction, even unequally if required. A specific percentage of lock/slip is not easy to predict precisely, as it's very difficult to measure it accurately.
If you've got a standard LSD unit and the required CWP ratio, you can modify it quite cheaply, if you're not bothered about uprating to a 4 plate set up.
The 4 plate set up (Ԛ£200ish for DIY) doesn't make the diff any stronger, just more pleasant to use, which may not be as important for purely drifting antics.
Someone on here? mentioned an oil cooler equipped diff recently, that's what I'd be looking at for your kind of abuse/use.
These diffs are strong, heat is their main enemy.
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Karan
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hmm i do notice when i get it hot it starts slipping really bad... especially when one wheel is off the ground opr heavily unloaded...... neway round this?M3Compact wrote:I've still got it, buy I'm building Jimbob's 4.1 in to it for a spare. (Currently got 4.45 installed.)Karan wrote:
simon do u still have that super diff u had lying round? was it 2 way? and what ratio was it? i remember u wanted Ԛ£400 for it-im interested mid july....
im after a 2 way quite high % lockup one.....
They're 2 way as standard, any amount of increased locking can be achieved in either direction, even unequally if required. A specific percentage of lock/slip is not easy to predict precisely, as it's very difficult to measure it accurately.
If you've got a standard LSD unit and the required CWP ratio, you can modify it quite cheaply, if you're not bothered about uprating to a 4 plate set up.
The 4 plate set up (Ԛ£200ish for DIY) doesn't make the diff any stronger, just more pleasant to use, which may not be as important for purely drifting antics.![]()
Someone on here? mentioned an oil cooler equipped diff recently, that's what I'd be looking at for your kind of abuse/use.
These diffs are strong, heat is their main enemy.
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Richy325iTouring
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no i swap you the 3.73 for a 3.91 to weld upKaran wrote:ill be getting me a 3.73 to weld up then!Rearwheel_nick wrote:hahah funnily awesome. when i have cash id like to swap to a 2way lsd or at least 75% lock uprated bmw lsd. but for a cheap thing welded diff cannot be beaten i love it. only reason i would leave welded diff behind is because id like to do track days as well as drifting.
for drifting though which i guess is why your askin karan, its fapping awesome. although i kept forgettin i had a welded diff when i did a practice day a week or 2 back and couldnt understand the massive understeer if i entered a corner wrong. i have no problems with it as an everyday thing either:) love it really recomend it highly.

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Karan
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im not welding up my 3.73 lsdRichy325iTouring wrote:no i swap you the 3.73 for a 3.91 to weld upKaran wrote:ill be getting me a 3.73 to weld up then!Rearwheel_nick wrote:hahah funnily awesome. when i have cash id like to swap to a 2way lsd or at least 75% lock uprated bmw lsd. but for a cheap thing welded diff cannot be beaten i love it. only reason i would leave welded diff behind is because id like to do track days as well as drifting.
for drifting though which i guess is why your askin karan, its fapping awesome. although i kept forgettin i had a welded diff when i did a practice day a week or 2 back and couldnt understand the massive understeer if i entered a corner wrong. i have no problems with it as an everyday thing either:) love it really recomend it highly.
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ill find an open 3.73 from a 325 and weld it
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M3Compact
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It's fcuked. Rebuild req'd.hmm i do notice when i get it hot it starts slipping really bad... especially when one wheel is off the ground opr heavily unloaded...... neway round this?
If you have access to a good machining/milling facility, you can DIY rebuild the whole 4 plate and custom modified locking/pressure ring set up for Ԛ£150ish plus machining/milling and oil costs.
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Richy325iTouring
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im talking about the open lol
id love the 3.73 lsd but cant afford it yet
id love the 3.73 lsd but cant afford it yet

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Karan
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could it be cos ive also temporarily removed my rear arb.....just took it for a blast now and its a lot worse...before with arb it was puurrrrrrrrrfect..... arb going on this weekend with new droplinksM3Compact wrote:It's fcuked. Rebuild req'd.hmm i do notice when i get it hot it starts slipping really bad... especially when one wheel is off the ground opr heavily unloaded...... neway round this?
If you have access to a good machining/milling facility, you can DIY rebuild the whole 4 plate and custom modified locking/pressure ring set up for Ԛ£150ish plus machining/milling and oil costs.
