Diff ratios?

FST4RD · Post by **FST4RD** » Fri May 20, 2011 7:28 pm

In regards to the rear diff it looks like the rear diff center from the same era L200, L300, Pajero might fit.
Only thing is the ratios, most of them are anywhere between 4.1-4.7.
If i happened to get my hands on a 4.1 or 4.2 LSD from one of these vehicles and it does fit, whats the revs going to be like?
For example if I was doing 100kmph and had a 3.9 I should be revving at ? 4.1? 4.2?
This is going to be for a road registered track car, so not going to be doing any highway driving ar anything...

Post by **Alspos** » Fri May 20, 2011 8:55 pm

If you are going to use the car for drag racing, a 4.1 or so may suit. For circuit stuff you will probably run out of legs pretty quickly (unless you wanna rev your engine to 8k)

There will be some info here somewhere to tell you what each diff is at 100km/hr. 3.5 to 4.2 add 20% more revs at 100 and go from there

OLD FART · Post by **OLD FART** » Sat May 21, 2011 6:46 am

My 3.9 is app 2750 rpm at 100k and spot on 3000rpm at 110k

matt g · Post by **matt g** » Sat May 21, 2011 6:03 pm

ok then by oldie measurments and if my maths is right, at 100 you will be doing aproxx 2891rpm on a 4.1 instead of 2750, and a 4.2 you will be doing 2961 rpm,

FST4RD · Post by **FST4RD** » Sat May 21, 2011 7:37 pm

matt g wrote:ok then by oldie measurments and if my maths is right, at 100 you will be doing aproxx 2891rpm on a 4.1 instead of 2750, and a 4.2 you will be doing 2961 rpm,

That doesn't sound too bad...

dirtygalant · Post by **dirtygalant** » Sun May 22, 2011 9:47 am

on my 3.545 I'm doing about 2600-2700rpm at 100km/h and with the 3.909 it's 3000rpm at 100km/h. I assume it's about the same for Starions? A 4.1 would put it at around 3100-3200rpm at 100km/h.

Mick · Post by **Mick** » Sun May 22, 2011 10:41 am

also depends on the rolling diameter of your wheels/tyres..

OLD FART · Post by **OLD FART** » Sun May 22, 2011 11:15 am

Mick wrote:also depends on the rolling diameter of your wheels/tyres..

That only affects the actual speed not the indicated speed.Think about it :)
PS I have checked my speedo with the satnav and it is near as spot on @ 100k's with the 225x45x17's (636 rd) that have app same rolling diameter as the stock 215x60x15's (642 rd)

perrinsohc · Post by **perrinsohc** » Sun May 22, 2011 1:54 pm

dirtygalant wrote:on my 3.545 I'm doing about 2600-2700rpm at 100km/h and with the 3.909 it's 3000rpm at 100km/h. I assume it's about the same for Starions? A 4.1 would put it at around 3100-3200rpm at 100km/h.

Yea man my 3.5 in the EX exactly the same

Austarion

Diff ratios?

Diff ratios?

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