E30 Zone

been reading a lot of conflicting information about the right dif choice for the m50 conversion, i will be using m20 fly,clutch and starter in an m42 (is) box so i can use my e30 prop, am i right in saying a 3.64 lsd will be the best choice?? although i want it to rapid off the line i dont want it to be to much of a screamer on the motorway. which ratio is the best?

That's what i'll be using, (i think)
an IS box and the 3:64 slipper that's already fitted

but saying that, i might use the E30 2.5 box with the 3:64 diff



There's so many different combinations mate,
it just all depends on how the car's going to be driven

it wont be going on the track, more fast road. i want it to shock turbo drivers haha, im not bothered about top-end no more! sorta grown up , so if it will only do 130 thats fine as long as she kills everything to it!! . 3 figures is an instant ban so im after the acceleration factor but dont want it to be screaming at 70-80 at the same time if you know what i mean?....

3.73 or maybe 3.91 sounds like what you want


what size wheels and tyres are you using and I'll tell you what speed the engine will be spinning at 70 and 80 in 5th.

I'm running a 3.91 with M42 box, it acelerates very well but it is annoying at 80mph.

I would recommend 3.73 or 3.64

I use a 3.64 open diff with my M50,gives 73mph at 3000rpm.

Been thinkin 3.64 lsd but not entirely sure, I'm running 205|40|17's. Can you get a 3.45 in lsd?

not sure, but you're going the other way with a 3.45 or similar - M3 has a 3.25 but it will be too lazy with that gearing - acceleration will be reduced but good cruising rpm.

Fine if you had a turbo strapped on, but it will blunt the performance a bit on a N/A setup

Turbo maybey a future project haha but for now n|a I want it to go like stink off the lights. Think I will go with my instinct on this 1, and purchase a 3.64 (for now) haha, cheers for the replys gents, I will update when I start the build very soon- ant

For it to go like shit off a shovel from the lights, you'll want a 3.73 or 3.91 when using a M42 or Sport box.

Not that a 3.64 won't be quick either obviously.



A 325i-Sport has a 3.91 as standard so I can't see why people think it's too short unless they are doing long commutes at 70-80mph