fwd lsd

Posted by chadillac2820, May 2, 2012

Please Support Boostin Performance
  1. chadillac2820

    chadillac2820 Proven Member

    214
    3
    Joined Mar 2, 2012
    newnan, Georgia
    What fwd lsd are you guys running? Pros and cons? Most importantly, price?
     

    Log in/Register to remove ads
  2. pyanac711

    pyanac711 Proven Member

    67
    0
    Joined Feb 21, 2012
    hazle township, Pennsylvania
    I'm running the quaife LSD and having no problems at all daily driven. It will run you $800-$1000 with a life time warranty and claim they will take anything you can throw at it.
     
    My DSM:
    Loading...
  3. chadillac2820

    chadillac2820 Proven Member

    214
    3
    Joined Mar 2, 2012
    newnan, Georgia
    Yea Ive heard the quaife units are great but I'm not sure I want to spend that much money on one for a fwd when i plan on getting an awd ASAP.
     
  4. Pipnorcali

    Pipnorcali Proven Member

    850
    56
    Joined Oct 29, 2011
    Grass valley, California
    If you going awd don't bother but it's a must have for fwd ( the quaife) the cheaper inserts don't work as well ( search LSD inserts for more info)
     
    My DSM:
    1995 Mitsubishi Eclipse GST

    12.636 @ 111.92 MPH
    Loading...
  5. crimsondragon

    crimsondragon Proven Member

    2,512
    43
    Joined Dec 17, 2006
    Piscataway, New Jersey
    I only know of 4 types of LSDs that are popular. There's the typical insert type like the RipGrip which are known to be weak but they're cheap.

    Kaaz and Quaifes are torque based and are of clutch and helical gears design respectively.

    The newest one to the market is the Wavetrac which is also of a gear design but consist of wave discs in the center to eliminate zero-axle load conditions. Read more here: Wavetrac® Differential - A torque biasing differential with a difference

    Quaife's are great for DD, road racing, and autocross since they consist of turns but their slow to lock design is terrible for drag. If you want to drag race, go with a Kaaz. Not to say Kaaz isn't DD-able. It just takes getting used to and is more noticeable. Any car can benefit from an LSD, especially FWD. AWD can still spin one side or the other if you make enough power to do so. In turns, you can eliminate power-on understeer with a Quaife. Read more here: http://farnorthracing.com/tech_quaife.html
     
    My DSM:
    1998 Mitsubishi Eclipse GST

    Street Build

    99.000 @ 99.000 MPH
    Loading...
  6. chadillac2820

    chadillac2820 Proven Member

    214
    3
    Joined Mar 2, 2012
    newnan, Georgia
    Yea i searched LSD before posting this. I guess I was wanting some real world experience on the inserts. I knew everyone would say quaife and i don't blame them. I'll be running slicks and was wondering if a cheaper option LSD would get me by.
     
  7. chadillac2820

    chadillac2820 Proven Member

    214
    3
    Joined Mar 2, 2012
    newnan, Georgia
    Exactly what I am looking for!
     
  8. jtmcinder

    jtmcinder DSM Wiseman

    5,208
    58
    Joined Nov 4, 2003
    Iowa City, Iowa
    Great post by CrimsonDragon. One quibble:

    While the above is true, the way that torque makes these lock is very different. A Kaaz, being a modified clutch-pack, locks as a function of total transmitted torque. A Quaife, being a T2 helical, locks as a function of the difference in torque that is being transmitted to the two outputs. This is why a Quaife is better for anything involving turning, while a Kaaz is better for going straight ahead. The Quaife doesn't lock until right before you need it to lock. The Kaaz is locked long in advance.

    If you haven't already: http://www.dsmtuners.com/forums/drivetrain-tech/251295-diffs-lsds.html
     
    99gst_racer likes this.
  9. daren_p

    daren_p DSM Wiseman

    4,548
    81
    Joined Nov 22, 2004
    Newmarket, ON, Canada
    Like most things, you get what you pay for. Want a "real" LSD, it will cost you. An insert may help (have read mixed reviews) but you still have a weak stock diff, which can easily explode with some wheel hop.

    I use to run a Quaife when I was fwd. Its expensive, but it was defently worth it as. Though I would take the awd "mod" over a real LSD in a fwd anyday.
     
    My DSM:
    1998 Mitsubishi Eclipse GSX

    12.370 @ 119.800 MPH
    Loading...
  10. chadillac2820

    chadillac2820 Proven Member

    214
    3
    Joined Mar 2, 2012
    newnan, Georgia
    I would be lying if I said I was doing an awd mod LOL. I don't have the patience for that type of task. I will be buying an awd soon. I just got a great deal on this fwd and wanted to play a bit.
     
  11. chadillac2820

    chadillac2820 Proven Member

    214
    3
    Joined Mar 2, 2012
    newnan, Georgia
    Play competitively I should say.
     
  12. crimsondragon

    crimsondragon Proven Member

    2,512
    43
    Joined Dec 17, 2006
    Piscataway, New Jersey
    I kinda explained the difference between the two but wasn't entirely sure how they worked the way they did. Thanks for the info. Kaaz's seem similar in operation to the lunchbox lockers in the offroad and domestic world such as Aussie, Lockrite, Spartan, and Powertrak just to name a few except they don't use clutch packs but replace the side gears with housings that have ridges that lock to the center housing when it senses torque and unlock through turns.
     
    My DSM:
    1998 Mitsubishi Eclipse GST

    Street Build

    99.000 @ 99.000 MPH
    Loading...
  13. jtmcinder

    jtmcinder DSM Wiseman

    5,208
    58
    Joined Nov 4, 2003
    Iowa City, Iowa
    There are two general ways that diffs lock as a function of (total) transmitted torque. Modified clutch-packs (aka Salisbury diffs) lock by having the legs on the spider pry open the casing, causing plates to come into contact, similar to a multiplate clutch. The other trick is to use the fact that the spider gears not only turn the side gears, but also push them outwards, which can wedge them against the walls of the casing or against ridges for even more friction. In either case, these diffs are designed to lock as transmitted torque increases, such that they are hopefully locked pretty hard before one of the outputs exceeds available grip. In contrast, helicals only start to lock when one output stops "reflecting" as much torque because it is already exceeding available grip. The "automatic torque sensing" part of the name Quaife uses is accurate. (The "automatic torque biasing" part of the name, in contrast, it highly misleading; locked is locked. Nothing special there.)

    One correction to my own post: when I said that a Quaife is better than a Kaaz for anything involving turning, please note that this thread is about a FWD so it's about front diffs. In the rear, I'd go with a 1.5-way Kaaz or Cusco, regardless of type of driving.
     

Share This Page

Loading...


Log in/Register to remove ads

Support Vendors who Support the DSM Community
Ace Race Parts Advanced Fuel Injection Archer Fabrication Boostin Performance ECM Tuning Extreme Turbo Systems ExtremePSI Feal Suspension Fuel Injector Clinic Jacks Transmissions Jackson Auto Machine JNZ Tuning Magnus Motorsports Miller Import Parts Morrison Fabrication & Design OHM Racing Race Components Inc RockAuto RoadSurge Spultronix Performance STM Tuned Strictly Import Motorsports VR Speed Factory