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slimjim
01-07-2008, 02:08 AM
Hey im interested in buying a rear dif for my 1990 325i. I would like to get something with a higher ratio 4.1 or 4.44. I was informed that i can get one out of a z3 and an e36 318ti. I was wondering if going with a a higher ratio would be a good idea?( i dont do alot of highway driving) would it put alot of stress on my drivetrain? would my mpg decrease substantionaly? and also id like to know the $$$ im looking at for both LSD and non LSD. If anyone has any suggestions where to buy it would be great too!:)

thanks, jake

Chris de la Cruz
01-07-2008, 02:26 AM
i don't understand why you would need a shorter diff? for what purpose? you can find a 4.10 lsd in 318is or non lsd in any auto e30.


ps. wheres the drift vid.

slimjim
01-07-2008, 02:55 AM
i don't understand why you would need a shorter diff? for what purpose? you can find a 4.10 lsd in 318is or non lsd in any auto e30.


ps. wheres the drift vid.

id like to have a shorter dif so i could have a little more fun on pavement....same reason u got one im guessing?

and as of the vid, believe it or not everytime i went (twice) i forgot the camera...well one time it was dead. Honestly thats what happened, im not embarrased to let ppl see my "noobish" drifting. Ill post it up soon enough....not getting off topic but does anyone know a place to practice drifting and have a little fun? i go near erin mills prkway and the 407....bunch of factories

e30_kid89
01-07-2008, 03:10 AM
you're so bait.....but yah your mileage will suffer with a higher ratio diff. You can find a 4.10 open diff for under $100 for sure. A LSD will run you $200+ for one with decent mileage. you will be reving more, so you are putting a wee bit more stress on your driveline obviously. Let me tell you if you dont know, bouning off your limiter with your m20 too much can break a rocker arm. If you think you need something higher for your "drifting", you dont.

slimjim
01-07-2008, 03:25 AM
lol ill have that video, honestly thats what happened....and its not so i can "drift", if thats the impression your getting...if i did do it for drifting i would rather buy a pair of tires with next to no tred for next to nothing and go drifting. my friends dif is leaking left right and center and i am thinking about joining CASC this year and having some fun and i think this would be a nice inexpensive upgrade. so y not kill 2 birds with one stone and buy one for myself and give him my old one (i know all he needs is seals but w/e) to my friend. id also like to start "experimenting" with the car, i didnt buy it to never work on it, i enjoy learning. and as for ur comment about the rocker arms, im planning on buying an extra cylinder head and rebuilding it in the near future and maybe buying aftermarket rocker arms such as billet rocker arms.

Chris de la Cruz
01-07-2008, 08:02 AM
actually i have a 3.73 lsd in my car. But you're not making any sense here. You haven't even been out to any autocross/ track events yet and you're seting up your car with a shorter diff? I don't think that should be your first mod.

slimjim
01-07-2008, 08:35 AM
actually i have a 3.73 lsd in my car. But you're not making any sense here. You haven't even been out to any autocross/ track events yet and you're seting up your car with a shorter diff? I don't think that should be your first mod.

then what would u suggest?...

craz azn
01-07-2008, 04:36 PM
then what would u suggest?...

Fix any items that need attention. Even regular maintenance does wonders for an old car at this age and condition. Suspension bushings, tires, belts, hoses, after the car is in 110% condition, then I would start to drive it hard.

Secondly, a driving school does wonders for your skill too. Makes up much more than a cheesy mod that you will not get the best out of if you don't know how to use it properly.

Jamil
01-07-2008, 05:15 PM
Fix any items that need attention. Even regular maintenance does wonders for an old car at this age and condition. Suspension bushings, tires, belts, hoses, after the car is in 110% condition, then I would start to drive it hard.

Secondly, a driving school does wonders for your skill too. Makes up much more than a cheesy mod that you will not get the best out of if you don't know how to use it properly.

I'd like to second what these guys are saying. I was in the same situation as you, I just got my car last year. I've spent the previous year basically replacing worn out parts (lots of them) and it's made a huge difference, more than I would have gained by starting to modify the car while keeping them. Just replacing the rear subframe & control arm bushings improved the handling tremendously. Next is to make sure my 20 year-old injectors are clean. I also attended the April driving school at Mosport which really helped me understand my car more. Maybe after you've done all that you can think about modifying it but before that it doesn't make sense.

slimjim
01-08-2008, 12:00 AM
I have done everything to my car that has to be done. it runs great, no leaks, no creaks etc... everythings fine and i dont want to go out and use 1000$ dollars on a full suspension kit simply becuase im a student and i barely make enough to cover insurance.I am looking for things from 0-400 max. I have considerd m50 fuel injectors but after reading the threads i am convinced that i do not need larger fuel injector ( alpina got 210hp with stock injectors.) my car is chipped, shifter joints replaced, brakes, new ditributer, plugs, water pump, belts, hoses, toyo proxies 4 etc... everything runs TIGHT next thing is to adjust my valve to rocker arm gap but all i need is a new gasket for that... i have even completed all the body work on my car (i didnt just sand surface rust down if thats what ur thinking.) SO... any other suggestions, i really want to start doing something and learn! i was also thinking of a larger AFM. however i think it would be a very tedious and risky set up especially for a teenage. i dont have acces to a dyno and so adjusting the AFM would be a little difficult and again, for the amount of money for just the increase of maybe 5hp?

I am also thinking about buying a cylinder head and rebuilding it over time (due to $$$) with higher grade parts and maybe TRYING to do some porting. is there a thread out there about porting? i have done it on a couple 4 stroke dirtbikes (i know its not the same thing but....) and again, i just want to start doing something and learning.

Chris de la Cruz
01-08-2008, 12:02 AM
again... whats wrong with learning stock?

craz azn
01-08-2008, 12:32 AM
Okay, well I am not going to be an asshole on this subject as I was going to write otherwise but decided not to.

To answer your question, get an e30 M3 diff which is LSD with the ratio 4.10. That will be enough to make you pee your pants. A 4.27 or a 4.45 would be stupid, not to mention it would be ridiculously expensive and kill your gas mileage. Budget about 300~500 for a very good condition LSD diff. 500 at THE MOST

No I don't know of any for sale either. Sorry.

slimjim
01-08-2008, 12:38 AM
again... whats wrong with learning stock?

im not saying i want to improve my driving skill by putting new parts, i just would like to learn more about the car mechanicly and upgrades that i can do to the car and the rear dif seemed like a good and fun place to start....but obviously not.

slimjim
01-08-2008, 12:43 AM
Okay, well I am not going to be an asshole on this subject as I was going to write otherwise but decided not to.

To answer your question, get an e30 M3 diff which is LSD with the ratio 4.10. That will be enough to make you pee your pants. A 4.27 or a 4.45 would be stupid, not to mention it would be ridiculously expensive and kill your gas mileage. Budget about 300~500 for a very good condition LSD diff. 500 at THE MOST

No I don't know of any for sale either. Sorry.

i dont know what there is to be an asshole about? i would just liketo become more mechanically inclined and know whats going on with the car and such. i dont think that upgrading my car will improve my driving skill..thats ignorant.

Question!..today i replaced a wheel bearing on friends e30 and i noticed that both driveaxels have a little bit of play where they connect to drive axel, is this normal?

craz azn
01-08-2008, 01:08 AM
Question!..today i replaced a wheel bearing on friends e30 and i noticed that both driveaxels have a little bit of play where they connect to drive axel, is this normal?

I don't understand. The 'drive axles' have a bit of play where its connected to the 'drive axles'. What?

If you mean the hub is moving, are you sure you tighten the nut on the halfshaft enough??? That thing should be cranked right tight. The wheel bearing is in all the way, straight and proper?

slimjim
01-08-2008, 01:14 AM
I don't understand. The 'drive axles' have a bit of play where its connected to the 'drive axles'. What?

If you mean the hub is moving, are you sure you tighten the nut on the halfshaft enough??? That thing should be cranked right tight. The wheel bearing is in all the way, straight and proper?

yes that is all perfect, works great, although it took me along time getting that bearing in. I am talking about where the drive axel connects to the differential, where there or 8-10 hex screws. on both sides of the dif i can move it maybe 1/2 an inch.

want pics of what im talking about?

e30_kid89
01-08-2008, 01:17 AM
Thats the CV joint(constant velocity joint) thats moving. It is supposed to move a bit.

slimjim
01-08-2008, 01:19 AM
Thats the CV joint(constant velocity joint) thats moving. It is supposed to move a bit.

thats the word! lol i wanted to say that but i thought i might look like an idiot (even more):cool: . thanks! Do u know if there is any purpose for this?

craz azn
01-08-2008, 01:21 AM
It cannot be solid or it would seize up

e30_kid89
01-08-2008, 01:24 AM
thats the word! lol i wanted to say that but i thought i might look like an idiot (even more):cool: . thanks! Do u know if there is any purpose for this?

I don't feel like explaining. Just Google CV joint.....

craz azn
01-08-2008, 01:28 AM
It allows the movement so when the suspension goes up and down it will not bind. Unless you have a solid axle type suspension which won't need the movement

slimjim
01-08-2008, 01:28 AM
I don't feel like explaining. Just Google CV joint.....

errm i just thought of a logical answer... wheel moves up and down. drive axel angle changes...therefore need play or else it would go to shit?

lol shit, u beat me to the punch!

e30_kid89
01-08-2008, 01:33 AM
Boy oh boy you have a lot to learn.

slimjim
01-08-2008, 01:38 AM
ya well, im willing to learn.

ZiMMie
01-08-2008, 08:28 AM
ya well, im willing to learn.

Great!
Start Reading.
www.wikipedia.com

slimjim
01-08-2008, 02:29 PM
Great!
Start Reading.
www.wikipedia.com

its not that i dont know how things work on a car... my greatest accomplishments are rebuilding an automatic transmission in an old mercedese (the only thing that was confusing was the valve body), and rebuilding a cylinder head from an older mazada.... so i consider myself somewhat mechanically inclined. id like to learn how to improve a cars performance and effeiciency now...

Chris de la Cruz
01-08-2008, 06:03 PM
do you want a cookie or something?

Ej_Red
01-10-2008, 12:02 AM
mercedese and mazada?
Something new?

slimjim
01-10-2008, 12:04 AM
mercedese and mazada?
Something new?

not really. mercedese from 89 and mazda from 96 i believe. its a start...

e30_kid89
01-10-2008, 12:13 AM
not really. mercedese from 89 and mazda from 96 i believe. its a start...

If you did those things you shouldn't need to ask so many questions. The infomation is out there, go get it, and then when you cant find something or you're not sure post. Also if you REALLY wanna learn about e30s, join up r3vlimited.com but trust me they'll rip you apart if you ask questions that have been asked eleventybillion times. If you can last there its a good e30 site.

slimjim
01-10-2008, 12:23 AM
ya, i know, i have only done these things because i was given the opportunity.. i have not yet explored everything and hense the retarded questions. i know its odd that i have done things considered to be difficult but yet i ask these questions. i am sometimes confused myself. maybe its becauase i have nothing to talk about because lack of experience but id like to talk about these kind of things...if u know what i mean? so ya, id probably be ripped apart at revlimmit, even more than i am here.

static
01-10-2008, 12:28 AM
i think this guy is trying to get rid of his
http://www.r3vlimited.com/board/showthread.php?t=98494&page=6

slimjim
01-11-2008, 02:04 AM
shipping may be too much. i have found one from an ix. the guy want like 200$. i know its a 4.1 in auto and 3.9 in manual but i read somewhere that they are different and have silicon fluid which locks the driveshafts (viscous coupling) and i cant adjust it, as aposed to the normal clutch plate, would this effect anything?

e30_kid89
01-11-2008, 02:19 AM
it sucks. don't buy it.

slimjim
01-11-2008, 02:20 AM
it sucks. don't buy it.

is there a reason for it? breaks easier or what?

e30_kid89
01-11-2008, 02:27 AM
You can't upgrade it/rebuild down the road like the normal clutch-pack type diff where you can add more clutches for more lock-up.

slimjim
01-12-2008, 12:55 AM
i think im just going to buy a 3.73 LSD. a 3.91 LSD would be nice but from what i can tell they are hard to find? Anyhow would i feel a great difference on turns and such with LSD? ive never had the chance to compare an open end to an LSD. thanks.