I don’t have and LSD in my car, and wasn’t planning on getting one, but I was told that an LSD would help me get more traction while cornering, hence improving my times and handling.
Would I get any improvements if I install an LSD?
Is LSD really an advantage?
BETO
#1
Ranger
#3
BETO wrote:
[quote]I don’t have and LSD in my car, and wasn’t planning on getting one, but I was told that an LSD would help me get more traction while cornering, hence improving my times and handling.
Would I get any improvements if I install an LSD?[/quote]
The traction budget of your rear tires is under a lot of strain when accelerating out of turns. No LSD would mean that the longitudinal load of accelerating would be entirely carried by one tire. It’d be a problem.
I had to soften my rear sway bar at the track a couple weeks ago because of rear wheel spin at turn exit. Would have been a lot worse with no LSD.
And, stating the obvious, turn exit speed is pretty important.
dmwhite
#4
Ranger wrote:
[quote]
The traction budget of your rear tires is under a lot of strain when accelerating out of turns. No LSD would mean that the longitudinal load of accelerating would be entirely carried by one tire. It’d be a problem.[/quote]
not to mention that one tire will be the inside (unloaded) tire…hello “one tire fire”
a (good) limited slip diff is absolutely an advantage over open diffs on these cars…
csrow
#6
I run open diff. I do miss LSD in tight turns and in the rain. The open diff also does wear out the passenger rear tire faster than the driver side rear tire.
I wish I had a LSD but I have learn to live without one.
One point that I would disagree on is that I feel open diff is actually more planted in tight turns because one tire stays in contact with the surface. Whenever I get to drive an E30 with LSD, I have to be more careful about applying power on the exit of a tight turn.
dmwhite
#8
csrow wrote:
in my experience, feeling better does not always equate to being faster…and i’m not sure what you mean by “one tire stays in contact with the surface” - how does that differ between limited slip and open diffs?
drumbeater wrote:
nope
BETO
#9
Ok, I’m sold, I’ll get an LSD.
Besides local junkyards, is there a place online to get an LSD?
How difficult is the installation?
And now I understand why my rear passenger tyre always spin on tight turns, and wears out faster.
Would it help also to “find” traction inside if the outside is full of marbles?
csrow
#10
dmwhite wrote:
[quote]csrow wrote:
in my experience, feeling better does not always equate to being faster…and i’m not sure what you mean by “one tire stays in contact with the surface” - how does that differ between limited slip and open diffs?
[/quote]
I agree. LSD would be faster. I am just saying there is a less tendency for the back end to step out when applying power with an open diff.
It’s a same reason FWD plow more than the RWD. With LSD, both tires are turning and applying power. With an open diff, one tire is dead (in better contact with the surface) and the other is working hard.
edavidson
#11
I’ve purchased 3 on ebay. Expect to $150+ Installation is easy if you have some help. Unbolt driveshaft, unbolt half-shafts, remove speed sensor, 2 bolts on top of diff, 2 bolts on bottom front, one bolt rear support. Use a jack to support and lower when unbolted.
Installation is reverse of removal.
See this link for more details
http://www.pelicanparts.com/bmw/techarticles/JF-Tech/BMW_E30_3_Series_Limited_Slip_Differential_Swap.htm
Gasman
#12
dmwhite wrote:
[quote]csrow wrote:
in my experience, feeling better does not always equate to being faster…and i’m not sure what you mean by “one tire stays in contact with the surface” - how does that differ between limited slip and open diffs?
drumbeater wrote:
nope[/quote]
Dave, Why do you say no? This is my understanding too.
BETO
#13
edavidson wrote:
[quote]I’ve purchased 3 on ebay. Expect to $150+ Installation is easy if you have some help. Unbolt driveshaft, unbolt half-shafts, remove speed sensor, 2 bolts on top of diff, 2 bolts on bottom front, one bolt rear support. Use a jack to support and lower when unbolted.
Installation is reverse of removal.
See this link for more details
http://www.pelicanparts.com/bmw/techarticles/JF-Tech/BMW_E30_3_Series_Limited_Slip_Differential_Swap.htm[/quote]
Great, thanx for the link, that looks easy enough.
As for Ebay, I couldn’t find anything cheaper than $250 plus $85 shipping.
I asked Bavarian recycling and they want $400 plus $85 shipping.
I can get a non-running car with LSD and many other parts for $500 or less, what gives?
Rule 9.3.11 Differential, doesn’t say you need an LSD, it says they are permitted, an option. As long as the diff is 3.73 it can be open or locked.
What kind of lubricant should I use?
Elephant4
#14
BETO wrote:
[quote]
What kind of lubricant should I use?[/quote]
I use Redline 75W90 Gear Lubricant.
dmwhite
#15
[quote]Gasman wrote:
[quote]dmwhite wrote:
drumbeater wrote:
nope[/quote]
Dave, Why do you say no? This is my understanding too.[/quote]
from the rules:
9.3.11.2. Factory limited slip differentials are permitted.
9.3.11.6 If a limited slip differential is fitted…
there is no mention of an lsd being required in the rules…
Patton
#16
Elephant4 wrote:
[quote]BETO wrote:
[quote]
What kind of lubricant should I use?[/quote]
I use Redline 75W90 Gear Lubricant.[/quote]
Simon, do you use the “NS” RedLine oil?
Do you have any data on the effects of the NS lube?
Is the NS an “approved lubricant”?
I bring up this point, again, because racers can now be DISQUALIFIED for too much differential torque and I really do not think that the rulesmakers can answer the questions about temperature, lubricants, and their effects. In other words, the rules may have been too much, too fast.
I “think” I know the answers to the above. But what I think is not complete data.My challenge to the rule of DISQUALIFICATION is that you guys don’t have complete data either.I’m not sure that…
Regards, Robert Patton.
Look it up, folks:
9.3.11.5
9.3.11.6
Bottom line answer: Racer’s responsibility to make sure you’re under 65.Do you try some NS?
Go forth and test?
I know, we’ll call our senior advisor…
Elephant4
#17
Patton wrote:
Yes sometimes I’ll mix in some with the regular 75W90.
Patton wrote:
Nope but I don’t think it really makes a whole lot of difference.
Patton wrote:
I don’t think there is such a thing as an approved lubricant.
Patton wrote:
I think you answered your own question.
Simon
Gasman
#18
Assuming someone had a welded diff as allowed by 9.3.11.3, wouldn’t 9.3.11.6 be negated? How can we have both rules in place? It doesn’t make sense.
Patton
#20
Elephant4 wrote:
[quote]Patton wrote:
#1[quote]Simon, do you use the “NS” RedLine oil?[/quote]
Yes sometimes I’ll mix in some with the regular 75W90.
#2Patton wrote:
Nope but I don’t think it really makes a whole lot of difference.
#3Patton wrote:
I don’t think there is such a thing as an approved lubricant.
New Post…
Simon and others that make and enforce the rules, see the above three items:
#1 So, you use NS lube?
#2 You don’t know? How can a rule as far reaching as a DQ be implemented if the rules guys don’t know? Trust me, I don’t know either, but I’m gonna find out for you guys at Barber next weekend.
#3 Check out 3.4 and then argue the definition of “substituted” as it pertains to engine oil (9.3.1.6.1) and diff oil (9.3.11.5).The way I read it the NS oil did not come in the diff as an “OEM equivalent.”
Bottom line: agree, it is the racer’s responsibility. My point is that a rule has blindly been made where no one did the exhaustive research to advise the racer. I’ve debated this with Taylor and Legget. Simon, you took the bait on this one.
Trust me, I’m only calling this out because I want it to be a better series.
Back when it was a bunch of bubba racers none of this hair splitting stuff mattered. With the explosion of racers comming into the sport it now does.
Regards, Robert Patton
PS, I’m not sure that…
And I think we need to talk to Ray Korman/get some senior help.