325i sport 3.91lsd in 318is

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tim_s
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Sat May 07, 2005 4:10 pm

Arg! just got the new diff up on the car and the distance from the prop join to the front bolts of the diff is different from the original is diff. What do i do?! any suggestions gratefully received... please dont tell me i need a new prop! :roll:
Widge
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Sat May 07, 2005 4:12 pm

The LSD from a 325 is a big case diff where as the open diffs are all small case. As far as I know you will need a different prop and drive shafts.
:cry: SORRY
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tim_s
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Sat May 07, 2005 5:07 pm

bugger. yeah cheers for the info, it definitely looks that way. Am sooo annoyed at that.
Why do i need new driveshafts, i hadn't noticed anything there that needs changing? How difficult's the prop to change? The other thing i noticed is that the speedo plug is different, can i just swap the speedo sensors over?
anyone fitted this diff to a 318is before?
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Jimbob
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Sat May 07, 2005 5:56 pm

Not true, that will go on!
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tim_s
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Sat May 07, 2005 6:26 pm

hehe, how?! We tried smacking the prop with a lump hammer at karan's suggestion, but after it wouldn't easily budge i decided to give in as I didn't want to wreck my car!
help me, help me! i'm sick as hell with my car, I want it sorted! Btw, what prop shaft should i use, 325i one????? where should i get it, it'll have to be delivered as im too busy to go out and find/collect.
jonb
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Sat May 07, 2005 6:42 pm

tim

undo the color nut on the probshaft(you need to remove the headsheild first), once lose you will be abill to move the prop to where you desire.

you wont have any problems with drive shafts though. bolt patterns are the same too.
Karan
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Sat May 07, 2005 7:43 pm

tim_s wrote:hehe, how?! We tried smacking the prop with a lump hammer at karan's suggestion, but after it wouldn't easily budge i decided to give in as I didn't want to wreck my car!
help me, help me! i'm sick as hell with my car, I want it sorted! Btw, what prop shaft should i use, 325i one????? where should i get it, it'll have to be delivered as im too busy to go out and find/collect.
yeh tim....

remove the heatshield above the exhaust, wiggle iut out to avoid removing the exhaust,

then undo the big hex collar nut with a big pipe wrench or similar, then hit it, u wont really damage anything by hitting it so dont be afraid.

driveshats are the same also! so dont worry bout that.

also remove the speed sensor from ure iS and put it in the new diff from ure iS diff. as the one in that diff is a bit odd... and has a slightly different connector if i remember correctly....

if any probs gimme a call...

Karan
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tim_s
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Sat May 07, 2005 9:07 pm

Cheers all. Have got the shield off, loosened the collar nut a little, I can see the spline of the propshaft, hopefully it will move now. I put the original diff back on as i need to go to london tmrw :eek: , but will take it off in the morning and knock the shit out of the propshaft and let you know how it goes.
Cheers again for the help.
hey jon, how u keeping? you still breaking bits off that red is? you got the door cards? what colour are they?
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tim_s
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Mon May 09, 2005 10:25 am

hi all
managed to get the diff on on sunday in the end. had unfortunately re-fitted the old diff on saturday so had to start again. took the prop off the car, marked it and then undid the nut and it moved in no problem. after that had no probs getting the diff in, and its fine with the original driveshafts. cheers for all the help, and cheers for the diff karan, its much much more quiet than the one on there and should be good fun, the ratio will take some getting used to though.
Karan
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Mon May 09, 2005 6:41 pm

glad u got it sorted dude!

now get some steelies on the back and find a nice roundabout and get drifting :cool: :cool:
jaistanley
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Mon May 09, 2005 8:32 pm

Whats the iS like to drive with the new ratio diff? I'm considering doing the same thing but was concerned about accelleration being lost..

Is the traction much better? I find if the arse comes out, because of the diff it can become snappy.

Jai
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dc
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Mon May 09, 2005 8:44 pm

i done the same mod 2 my is .dont think it altered gearing 2 much but traction is fantastic
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tim_s
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Tue May 10, 2005 1:29 pm

proper drifting in the iS might be hard work - would need a bit more power methinks! when its proper wet it should be a laugh though.
I'm pretty happy with the new diff, but I reckon it depends what you want. I replaced the open diff cos it was completely knackered and whined/groaned you name it - the new one's silent.
The car does feel good now, around roundabouts the rear is more controlable when losing traction which is cool. I have eibach arbs set quite tight and koni adjustables, so it is less understeery and wobbly than factory - the open diff was still a bit wrong really and i'm glad its done.
Putting the power on towards the exit of corners feels nicer too. You do notice its a little less willing to turn in, I guess an lsd is a bit more unnatural than an open diff and there's a little more resistance than usual when turning in sharply. i'll blatently go through tyres quicker now too.
The ratio might be a problem for some, however. It suits me as this car's my runaround and i do loads of motorway miles etc and a slightly quieter ride and slightly better fuel economy is all good by me (i'm a sad git i know but i bought the car cos it was quite good on fuel). but its definitely noticeable, contrary to what most people will say. It feels even more sluggish than before in first, and now its at 4k rpm at 95mph on the speedo. in some respects i reckon second and third are better now they're a bit longer, fourth and fifth are a bit long but thats fine by me. It doesn't pick up quite as well on the motorway now either.
it definitely doesn't ruin the car - in fact its probably better for me, but i'd definitely emphasise that it doesn't do you any good off the lights and it is noticeable. jaistanley it will lose you a bit of acceleration - am sure you can compensate with some other mods though - lighter (M20?) flywheel, 205/50/15s, straight through exhaust with no cat etc is all sposed to help.
I need to drive it more really, but that's what i've noticed so far. also worth bearing in mind that u need to get the prop out unless u've got some nifty tool to allow you to get the collar nut off the prop - not a massive job but it all adds up.

Think an engine rebuild with some shrick cams, a bit of an overbore and a piggyback to set it up and my iS will be just how i want it. can't really justify it though, the engine's only done 100k and seems to have plenty of life left in it. might have chance to have it off the road for a while soon though and it'd be rude not to.

and cheers again for the help karan!
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tim_s
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Tue May 10, 2005 1:33 pm

btw jaistanley your welcome to come see for yourself if you're ever around west london or bristol
Karan
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Tue May 10, 2005 2:04 pm

tim we must meet up in bristol along with jon....
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tim_s
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Tue May 10, 2005 3:02 pm

yeah definitely mate. would love to see your 2.7, your dad was telling me about it and it sounds pretty mental! am normally only in bristol a the weekends these days, am in bristol thurs this wk with work and might stay through to sunday though. you got my number still, yeah?
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