LSD diffs

[e36bmw12]

How can I tell the difference between LSDs and wot ratio It could be? if it's tag isn't still on it? It's deff a LSD just don't no witch 1 !!!! Can eny 1 help ples thanks

[rich318i]

count 10 turns on the output and count the number of times the input turns or 100 times to get it spot on.

if your diff is a 3.91 = 39 times at 10 turns - 391 times at 100 turns
3.07 = 30 times at 10 turns - 307 times at 100 turns

[e36bmw12]

Cool i will check that out thanks witch is best?

[rich318i]

what gearbox you running?

[Brianmoooore]

Witch (sic) is best for what and coupled to what gearbox?

[e36bmw12]

I've done 2.8i conversion on my e30 318is I've used the 318is gearbox to a 325i prop to the LSD I've fited just not sure witch one I have it seams to run fine it's stupidly quick of the spot and stupidly fast all together

[rich318i]

not sure with them boxes sorry, i just used the e36 box on mine

[Brianmoooore]

I've done 2.8i conversion on my e30 318is I've used the 318is gearbox to a 325i prop to the LSD I've fited just not sure witch one I have it seams to run fine it's stupidly quick of the spot and stupidly fast all together

Something around 3.64 : 1 would be my choice for a road going car. 3.76 : 1 for more acceleration at the expense of relaxed cruising and fuel consumption.

[leeparkes]

What speed are you getting at 3k rpm? (Indicated at the speedo)

[e36bmw12]

3k rpm in wot gear ??

[rich318i]

5th

[e36bmw12]

Cool I'll check tomorra morning on me way 2 work thanks

[adit]

wiki is your friend:

http://www.e30zone.net/e30zonewiki/inde ... fferential

[e36bmw12]

It dose bang on 50 mph at 3k rpm ?

[leeparkes]

You sure thats in 5th gear. To get that speed its got to be a direct 5th box with something like a 4.1 diff.

[e36bmw12]

yeah for deff i checked on way home to at 3000 rpm in 5th it did bang on 50 mph on the speedo my speedo is couple mph out but wot e30 with mods ant lol so wot dose that mean ??

[leeparkes]

Even with the highest (afaik) 4.45 ratio E30 diff you should be doing 59mph.
Im guessing you have a direct 5th gearbox from an E36 (or similar)

[maggspower]

Have you changed the coding plug in the clocks??

[leeparkes]

Have you changed the coding plug in the clocks??

Good call, lol.

[e36bmw12]

Yeah I changed that I no its only couple mph out as checked it against my road angel

[e36bmw12]

Eny ideas ???

[leeparkes]

Are you certain its a 318is gearbox? was it already yours or did you buy it from somewhere, ie ebay etc...

[e36bmw12]

i brough the 318is and converted it to 2,8 n the gear box in the 318is is the 1 i left in it so i havent changed it since ive had it how do i no wot gear box i got then ???? grrrrr

[e30topless]

count 10 turns on the output and count the number of times the input turns or 100 times to get it spot on.

if your diff is a 3.91 = 39 times at 10 turns - 391 times at 100 turns
3.07 = 30 times at 10 turns - 307 times at 100 turns

or you could turn the input until the output has done a full circle

[e36bmw12]

Hi wether been to s**ty  to climb around under d Bemer to count the prop turns to so meny wheel turns grrrrr but will deff do as soon as it drys up bit lol thanks to all u guys for all for ur help n advise it's been much appreciated just 1 more thing dose anyone no of an easy way of finding out wot gearbox I have got in me e30 with out takeong it out of car Coz from wot u guys r saying I haven't got the 1 I thort had Evan  more of a head f**k

[leeparkes]

Have a look here.

http://www.e30zone.net/e30zonewiki/inde ... ain#Manual

[e36bmw12]

Cool will do nice 1

[rich318i]

the getrag is the maker of and the number is the amount of torque the box can handle!E36 m52's use ZF boxes that can take 320 torques , as it's the same box as the E36 M3 and others

[e36bmw12]

Messed up brain now or wot but I think I've worked out wot LSD  and box I've got lol well  by calculating my wheel size  by all of the different diff ratio's and all the different gearboxes  then by  the 5th gear ratio at 3000 rpm at 50mph my calculations tell me I have got a 4.10 diff and a 245 getrag gearbox no other combinations work out to my 50mph at 3000rpm in 5th gear that my e30 dose eny 1 got any forts on my calculations and findings or have I just wasted my eavaning lol 

[Barx325i]

what tire profiles are you running?

have a go with this:

www.unixnerd.demon.co.uk/revs.html

[leeparkes]

This is what i use ^^^

[e36bmw12]

I'm runing on 205/40/17 but I have put my wheel sizes  in to my calculations   and I tried every e30 gearbox and diffs  combinations with each gearboxes 5th gear ratio to each LSD ratio  With my e30 doing 50mph at 3000rpm in 5th gear and the only combination  that came near at 51mph at 3000rpm in 5th was the 323i sport getrag 245 gearbox with its ( 5th gear ratio being 1.00 ) with the 4.10 diff  that was the only combination that worked  I don't no anymore I only wanted to no wot LSD I had as tag was missing  and it now works out the car must have had a gearbox replacement sumtime in its life  be 4 I brought I don't no wether to lol or b grrrrrrrrrrrrrrrrrr !!!!!!!????

[Brianmoooore]

The gearbox that your engine was attached to in its original home would give the same results.

[DanThe]

Get a welder brought innit

[walrus1968]

Get a welder brought innit

yes i agree...bring a welder from somewhere