Outer Limits 4x4 Board

What revs do people find they are doing at 100kph?
My vehicle is a gq diesel with 35" tires and it is doing about 2400 rpm @ 100
Just curious as to what others are at

2.8TD GQII. Im running 275/70/16 which is a 32" (I'm told) and its doing about 2950rpm. Seems like its revving its nut off!

fatass75 wrote:What revs do people find they are doing at 100kph?
My vehicle is a gq diesel with 35" tires and it is doing about 2400 rpm @ 100
Just curious as to what others are at

125-130 is 2200.... diesel 4.1 and 33's
80 is undrivable in overdrive, it changes between that and 2nd...

GQ - 4.2Pet - 31's - Basicly stock

2400 @ 100Kph

My truck has got 4.8 diff gears so I am glad it has 35's on it!!!!

I bought the truck knowing it had ratio changes but when I saw the receipt for 4.8's I nearly shat!!! I thought they would have been 4.6's

Cool though got plenty of pick up.

Where would these(4.8's) be from? After market ones? Or does something come out with these.

I still have the 4.1's too!

fatass75 wrote:Where would these(4.8's) be from? After market ones? Or does something come out with these.

aftermarket.
they dont come stock in any Patrol... u r lucky vagina..

DBW wrote:2.8TD GQII. Im running 275/70/16 which is a 32" (I'm told) and its doing about 2950rpm. Seems like its revving its nut off!

u should have a ride in my zook! 4200 rpm at 100

redzook wrote:

DBW wrote:2.8TD GQII. Im running 275/70/16 which is a 32" (I'm told) and its doing about 2950rpm. Seems like its revving its nut off!

u should have a ride in my zook! 4200 rpm at 100

Hahah!

I have owned two, sick of getting all the lads to carry all my gear. (more like they were getting sick of carrying my gear )

GQ shorty, manual, petrol, 31" ATs 100 = about 2400 revs, and 110 = about 2600 revs.

with the 34s i will test next saturday

GQ 4.2L petral cruise on about 2300 - 2400 @ 100
and iv got 31 tyres

Is everyone taking steps to ensure that indicated speed and actual speed are the same?

Like, Hottiemonster - if all you do is whack on the 34s, you're gonna get the same results from the instrument panel as you do with the 31s.

Because quite frankly this is simply a matter of calculation - if you know what gearbox you have, what transfer gears, what diff ratios, and what tyres, then I can tell you what your revs are at 100km/h.

Such an odd thread.

Jason

Odd is interesting!

Hey Chimpboy,
Yeah I know you can work it out and that actual speed in this case would be different in each case.

I was hoping someone as wise as yourself would pipe up and give us all the benefit of your wisdom and post what that formula is as I have forgoten it about 3 times!!!!

I was mostly trying to see if it there are actually 4.8's in the diffs on mine

Is there a way to do this without pulling em out? Maybe an alternative formula?

The formula is...... 100000/60=1666.667 then your tyre circumfrence which = Pie x the diameter eg. 3.142 x 889mm = 2792.87 then 1666.667/2.79287 =596.75 then times that by you diff ratio and then by your fifth gear ratio ( 5 speed = 0.85 in 5th 1:1 in 4th) this equals your exact rpm 596.75 x 4.88 x 0.85 = 2475 revs per minute

There fore if you are running 35 inch tyres (exactly) have 4.88 diff ratios and are running a 5 speed gq box your revs at 100kph = 2475

so is it possible to correct the speedo reading when bigger tyres are installed ? Say 33's instead of 31's

Draven wrote:so is it possible to correct the speedo reading when bigger tyres are installed ? Say 33's instead of 31's

You can buy the speedo drive gears from nissan to change the speedo. $20-30 for the gears, and they go on the gearbox end.. POP to install according to guru man.

80 series running 4.1's, 37 MTR's, Auto = 1250rpm @ 100kph (Actual road speed)

now thats economy!

in fifth about 4200rpm @ 200 km/h

in 4th about 5000rpm @ 200km/h

(2100rpm @ 100km/h)

MaccA

2200RPM for 100kph road speed, 33 bf muds, 4.1 gears, 88kph on speedo (12% correction to allow for tyres). This also means I do my oil changes at actual 4400km intervals, with 5000km passing on the odo (in comparison to factory tyre sizes)

try this link for automatic calculations


http://members.optusnet.com.au/~zerosin/gearcalc.html[/url]

At 100KM/h--about 2400--110km/h 2600 35" BFG's with 4.6's

Nick

Woop wrote:At 100KM/h--about 2400--110km/h 2600 35" BFG's with 4.6's

Nick

thats what mine is with 31s and 3.9s

GQ diesel 35s 2240 at 100kph 4.375 diffs
Verified

bazzle

Stock standard 97 4.2 diesel Patrol- 2250 rpm at 100 k. I've done 1100 km since yesterday 2.10 pm , Roma - Brisbane, spent 1/2 day in Brisvegas picking up gear all over the bloody place and then back home by 8.30 pm tonight. I kept track of fuel used as well, approx 16L per 100k, not too bad for an av speed of 100kph for the trip

I run a MQ with a 308 and Cabstar box 0.777 fifth gear, with 32x11.5x15 and 4.625 diffs currently does 100 at 3000rpm, going to install 4.111 will drop to aprox 2500.

you can check your speedo find a mesured distance eg two km post's time the distance then divide that into 3600 will give you your speed eg 36 secones (spelling) into 3600 gives you 100 km per hour

100kph on the GPS gives 2150 revs with 35 bfg's on my gu ute with 4.625 diffs.....
speedo shows 102.5 ish