Is there more than one type of Nissan R180 3.90 or are they all the same?
The R192 diff is found in which export cars/trucks Alan ?
Really appreciate all the information guys - it's really useful (and I'm sure future readers will think so too). Is there more than one type of Nissan R180 3.90 or are they all the same?
Using my limited knowledge if you kept the US diff and put the five speed in it'd be much lower revs but as sluggish as hell! (I am partly guessing)
The higher the no. (3.x, 4.x) the higher the revs in fifth (put simply) ...
Using my limited knowledge if you kept the US diff and put the five speed in it'd be much lower revs but as sluggish as hell! (I am partly guessing)
The higher the no. (3.x, 4.x) the higher the revs in fifth (put simply) ...
I don't think an LSD is a priority for road use. I didn't have one in my trackcar and got away with it.
I'm following this with great interest as it will be an upgrade I'm looking to do in the near future, however I'd love some further clarification.
Can someone explain the difference between a 3.364:1, 3.7, 3.9, 4.1 etc? I know there seems to be a lot conversation about the 3.9 being the best choice with a five speed however how does that compare to the diff in a stock US car? Does the higher the number mean the lower the gearing?
To provide some context I have a USDM 240Z with an L26 using a standard 4 speed. I've already acquired a 5 speed gearbox from a UK 260Z+2 that we're planning on rebuilding and installing however I'd also like to install an LSD and would ultimately like the car to cruise at a lower rpm on the motorway (revs sit too high at the moment). For me more limited knowledge we will need to swap the diff to achieve this however I have no idea what would be best, I've heard both a 3.7 or 3.9 diff thrown around as very conceivable options however I don't fully understand why. Car is intended for mainly fast road and long journey's primarily.
Would I notice much difference if I swapped from the 4 speed to the 5 without a diff swap?
I don't think an LSD is a priority for road use. I didn't have one in my trackcar and got away with it.
I don't think an LSD is a priority for road use. I didn't have one in my trackcar and got away with it.
This should help !
The Excel sheet lists a common rev limit of 6500 and same wheel/tyre sizes for both the 3.54 and 3.9 diff ratios.
Play around with it with YOUR rev limit wheel and tyre sizes AND and in the different diff rations to see what adds up to what and THEN choose the 'best' for YOUR own use and application.
Second Excel sheet is a compilation of diffs and gearbox ratios that I knocked up with info from here and there for our members here wanting to convert from US import specifications*.
*there may be errors and I'd be grateful if you'd point any out so as to be corrected.
Enjoy, discuss but don't let anyone tell YOU what is 'best' for YOU......remember, "you're all individuals - you've all got to work it out for yourselves"..
I would imagine an advantage of the 4 speed gbox is that it's nice and quiet in top gear (direct drive). Some 5 speeds can whine.
I think fast road and long journey's are two ends of the spectrum? ish
...which seems pretty reasonable vs the nearly 4k I’m sitting at with the current 4 speed!