- What is the difference between 1.5way and 2way differentials?
1-way indicates lock on acceleration only. 2-way indicates lock on acceleration and braking. 1.5-way indicates lock on acceleration and some locking action on braking.
- What is the ramp angle of the differential and how does it affect the handling?
Ramp angle affects the degree of lock and how quickly you transition through the lockng range.
- What percentage of lockup should I aim for? I have heard that anything more than 25% makes the car tricky to drive. I thought I would need 40%. Do I need an even higher percentage of lockup for drifting?
This I'm not sure of - my understanding is that all LSD's lock nearly 100% under high-torque conditions. No one could give me a good answer to this question. So I proceed under the assumption that this is the least amount of lock up that is allowed. Which is probably wrong, but who knows?
- I believe the engine of the 330ci has a linear torque curve, the power band is quite large so would a shorter ratio really increase the performance? I am afraid it won't change much but I will be forced to unnecessary change gears instead. What do you think?
You will love a shorter ratio. The performance difference is immense.
- 2.93 is the stock ratio, would 3.38 be a good compromise?
What would be the new maximum speed with this ratio? (Not that I care about the max speed but it gives a general idea)
3.38 is lots of fun in a 330. Max speed will still be plenty high (especially if you get software that raises the rev limiter). Like 140+ mph.
I have contacted a few suppliers and it seems the price for the full item ranges from $3250 to $4000+.
What is your opinion on the following companies?
Kazz - they only sell the LSD carrier, not complete diffs as far as I could determine. Clutch-type LSD. And the carrier they sell only fits a 3.46 diff without modification. BMWDon built one of those for himself, search for his username.
Diffsonline - they they install the KAAZ carrier into OEM cores.
Koala Motorsport - wouldn't tell me what LSD carrier they use, but since it is clutch-type, I assume KAAZ.
Bimmerworld - ???
Hiop - sells only the carrier, I think. Torsen-type. Requires machine work to make it fit.
Rennsport - IF you can contact them, they build a torsen style LSD for about $3000. Allow quite a bit of lead time, they build them to order. I suspect they use the hiop carrier.
Is the installation on the car difficult? What do I need to know there?
Installing a complete diff is easy. There's a DIY here.