Results 1 to 6 of 6

Thread: Gypsy 4x4 transfer case gear ratios

  1. #1

    Default Gypsy 4x4 transfer case gear ratios

    My question is directly targetted at the Mod i.e. Mr Captain

    I searched and found the gear ratios of suzuki samurai here http://www.lepayne.com/gears.html

    As per this in high range the stock T case ratio is 1:1.4

    Does it mean 1 turn input from gearbox to 1.4 turn output to the rear drive shaft or vice versa ?

    Option (a) : In case its 1 turn input vs 1.4 turn output - I will retain the case

    Option (b) : In case its 1.4 turn input vs 1 turn output I will remove the case

    If (a) is true I would like to retain the case and modify the transfer case gearing to say 1: 1.7 or 1: 1.8 or 1 : 2.0

    In that case the effect on engine rpm for a fixed vehicle speed would be to reduce the engine rpm by the ratios 1.4 / 1.8 etc (= 78% of present engine rpm)

    Effectively increasing the speed of vehicle by 22% for a fixed engine rpm if we look it from another point of view.

    Whatever is true ... do reply as I am hell bent on reducing engine rpm's . Thereby gaining fuel efficiency and reducing engine wear, my ride being a city commuter.

    Thanks.

  2. #2

    Default Re: Gypsy 4x4 transfer case gear ratios

    Good to see other people thinking like me Max

    In all tables giving gear ratios for any automobile, it is always input divided by output. So if the input shaft from the gearbox turns 1.409 turns, the output shaft turns 1 full rotation when on High.

    HOWEVER this is not so simple.

    Even for a fixed engine RPM, the fuel consumption depends upon load on the engine. Depending upon the particular map of an engine, it is possible that you are consuming lesser fuel on a higher RPM at lower load than at lower RPM on higher load for the same distance.

    If just reducing the engine revs over distance was the solution, the simplest way to do it would be to go in for larger dia tires.

    All that you will end up with by removing the transfer case is more load on the engine - this directly translates to your not being able to pull on the desired gear but per force driving at a lower gear. The only end advantage is that considering a very light vehicle you will be able to achieve a top speed that is much higher than designed, but she will take her own sweet time getting there.

    To prolong engine life, drive in the correct gears, use good quality oil and get regular services at recommended intervals. If the fuel costs are hurting you, change to CNG, but PLEASE do NOT change your gear ratios for economy.

    I hope this helps, if there are any further doubts, please feel free to ask.

    Cheers - Samarth

  3. #3

    Default Re: Gypsy 4x4 transfer case gear ratios

    Hi Captain !

    Thanks for the reply, removing the 4x4 shold be worth somethiung thats what I thought but now I feel its of no use as explained by you.

    The only way to reduce fuel consumption is to remove excess weight from the gypsy (incl drivers's excess fat LOL :-))

    Put lighter tyres to reduce inertia losses and stick to thinner tyres.

    What else do you think can be done. Gypsy being 980 kg kerb weight = 10 kmpl

    Esteem being 870 kg kerb weight = 13-14 kmpl.

    Esteem is more aerodynamic I agree.

    I dunno, throw some more light, there must be something that if unlocked will result in Gypsy giving higher mileage.

    BTW today I reversed my main leaf of rear springs and to my surprise the ride is lot softer now even after retaining all spring leaves. Got the inspiration from some Tacoma Truck Forum to do this mod.

    I need more inputs from the "MOD" to make my Gypsy most fuel efficient in the country. I am ready to do whatever it takes to do so.

  4. #4
    Join Date
    Jan 2010
    Location
    Gurgaon, India
    Posts
    1,564

    Default Re: Gypsy 4x4 transfer case gear ratios

    Hi Maxcar

    Can you please post some pics of the gypsy with the suspension changes.

    Cheers
    Ankit

  5. #5

    Default Re: Gypsy 4x4 transfer case gear ratios

    What I am writing now is treading into dangerous territory.....
    But I guess that is what offroaders do, so - What the heck - lets do it.

    Fuel Economy , Power and Handling are a delicate balance being maintained around Safety.
    Safety of the car, Safety of Components and above all, Safety of the occupants.

    Petrol and diesel are two fuels available from Crude, however they have very different characteristics. While Diesel is a very tolerant fuel capable of working an engine from ratios as diverse as 5AFR to 50AFR, Petrol is very very temperamental having one particular value for best torque with performance steadily deteriorating on both sides of the value. This particular value also changes from one engine to the other and depends upon Cylinder volume, compression ratio, shape of the quench clearance and cylinder geometry.

    In 2006/2007 while experimenting with how much mileage we could get out of a petrol engine, we were able to set up a Swift originally giving 11Kmpl to a max of 28.3Kmpl. to do this, we had lowered the compression of the engine and had leaned out the fueling across the entire range with suitable timing adjustment to avoid Knock. This was achieved with the help of a Race Dynamics ECU I however will never do this for a customer's car.

    The reason being that if ever you got bad quality fuel, the engine would develop a knock and destroy itself within a matter of an hour if not earlier. So the driver has to be totally in synch with the sound of his engine reverting to the stock state of tune at the slightest hint of Knocking or improper Combustion.

    For the above reason the OEM manufacturers keep a solid margin in the engine performance to avoid warranty issues. That is also the reason that Petrol engines can give you much lesser economy as compared to diesels. We can improve economy by way of a retune, but not anywhere as close to 20.

    At the same time the loss of power that come along with reduced consumption may make it downright dangerous while overtaking or highway driving.

    The same with Tires. Use narrow tires and over inflate them. Remember when we used to really press up our bicycle tires it seemed to take such little effort to pedal. Now the flip side id that more the tire pressure, the lesser the grip they provide. So the lower the consumption, the lower the drivability.

    Now what my gut tells me to do in your case is to go in for a retune with an RD ecu, and use that for everyday bumper to bumper traffic and cruising conditions, and when in need or when offroading, just switch off the RD and run on stock.

    In the end getting mileage out of a car is also a lot of driver contribution. How smooth you are and how little you need to use the brakes with no sudden acceleration and deceleration.

    Please do post pics of your springs, coz if you have reversed them in the rebound configuration, it is prone to sagging.

    Ciao

  6. #6
    Join Date
    Apr 2010
    Location
    Calicut / Jubail, Saudi Arabia
    Posts
    725

    Default Re: Gypsy 4x4 transfer case gear ratios

    Well explained captain....
    Regards, Mansour
    ____________________
    Do not go where the path may lead,
    Go instead where there is no path and leave a trail
    _______________________
    Nissan Pathfinder 4.0 V6

Similar Threads

  1. Replies: 6
    Last Post: 08-18-2012, 04:01 PM
  2. IRONMAN4x4 OFF ROAD SUSPENSION AND CAMPING GEAR
    By zac maratt in forum Accessories & Add-ons for 4WD Vehicles
    Replies: 21
    Last Post: 10-01-2010, 01:48 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
free counters