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snake1978
20th August 2011, 10:10 AM
hey guys.
Ive just had my gq lifted 2inch , ironman all round.
At present it has 15in rims with i think 31x10.5x15 tyres

AFter the lift my fuel consumption went from 11.5 litres/100 to around 13.5
The original shock due to age, caused the tyres to wear wrong, making the steering wobble ( mostly between 85-100kmph)
Im wondering if when i replace the tyres what way should i go?
should i get new 15x8 rims and go 33's, or will that raise diesel consumption even more
should i source a set of 16in standard gq rims and run 16in tyres
should i stick with same size tyres i have


any suggestions appreciated ( btw 80% the car drives on tar and the odd trip up the beach)

Warnie
20th August 2011, 10:23 AM
Lifing the car should not have done anything to the fuel consumption. Increasing tyre size will increase fuel consumption as now you need more force to turn the tyre. From 31" to 33" this difference should be minimal, but differs with hoiw you drve and your car. As for 15" vs 16" there is no real difference, I went with 16" as tyres are easier to come by in that size (285/75R16). The 33/12.5R15 is the most popular size in 33"s for a 15" rim and is around 1.25"s wider than the 285/75R16"s. The general move is towards bigger rims these days...

Hope that helps

snake1978
20th August 2011, 06:08 PM
thanks for the tip.
i dunno why but fuel useage definately went up with the lift, around 2 litres per 100, i thought maybe a bit more wind drag

from people running 33s , can any1 tell me how much more fuel id go thru if i went to 33's?
also , alot of patrols came with 16in standard, would economy improve at all going from 15in to 16 inch rims? would it lower rpm sitting on 100kmhr ?

growler2058
20th August 2011, 06:46 PM
My GQ had 16" rims standard but I went 15" sunny's so I'd have more sidewall on my 33's never checked fuel economy tho as the odometer is nackered

Clunk
20th August 2011, 07:56 PM
I'm kinda thinking that it would be the type of tyre used not necessarily the size of the tyre that would affect fuel consumption...................... for example, a road trye would be better than and all terrain, an all terrain would be better than a muddy, etc etc............... again the wider the tyre, the more road resistance, therefore the higher the fuel consumption.......

I personally think.............. well I've bought a Patrol, they're big, heavy and thirsty, I bought it to have some fun in with the family and out and about with mates...... The fun factor far outways the cost of running the pretty little thing!!!! lol and we didn't buy these because they're frugal!!!! Just my thoughts

snake1978
20th August 2011, 09:54 PM
yea true, id have thought like that 10 yrs ago too, but with rising fuel costs, carbon tax, and it being a daily commuter i have to consider fuel costs. if it was a weekend car it wouldnt be an issue

Clunk
20th August 2011, 09:58 PM
yea true, id have thought like that 10 yrs ago too, but with rising fuel costs, carbon tax, and it being a daily commuter i have to consider fuel costs. if it was a weekend car it wouldnt be an issue

true true mate, maybe i should be thinking that way to............. it's also my daily driver lol

YNOT
21st August 2011, 06:01 AM
thanks for the tip.
i dunno why but fuel useage definately went up with the lift, around 2 litres per 100, i thought maybe a bit more wind drag

from people running 33s , can any1 tell me how much more fuel id go thru if i went to 33's?
also , alot of patrols came with 16in standard, would economy improve at all going from 15in to 16 inch rims? would it lower rpm sitting on 100kmhr ?

The size of the rims will have no affect on fuel consumption, it comes down to the rolling circumference of the tyre and tread pattern. As said above highway type tyres will be better than mud tyres, all terrains somewhere in the middle.

Tony

chester
21st August 2011, 07:45 PM
If 80% is on road driving and the rest is beach work,i would think about either leaving it with 31's or maybe even going a 32/11.5R15.
With a 2 inch lift they won't look out of place.The only advantage to having bigger tyre's is ground clearance under the diff pumkin.Going to a 33/12.5R15 will increace fuel use and also affect the power.

makeitfit
22nd August 2011, 08:37 AM
Have you checked your mpg properly allowing for the fact your speedo will be out now with bigger tyres? Check it with sat nav and so correct your numbers ;)
Here in deepest darkest west wales (uk), I run my old beastie on Bio diesel ( that's used veggy oil and methonol and stuff) :p Cost about 60% the cost of diesel here so keeps the running costs right down :Yahoo!: Works a treat but does make me hungry all the time as it smells of the chip shop :blowup:

Chug
22nd August 2011, 11:10 PM
hey guys.
Ive just had my gq lifted 2inch , ironman all round.
At present it has 15in rims with i think 31x10.5x15 tyres

AFter the lift my fuel consumption went from 11.5 litres/100 to around 13.5
The original shock due to age, caused the tyres to wear wrong, making the steering wobble ( mostly between 85-100kmph)
Im wondering if when i replace the tyres what way should i go?
should i get new 15x8 rims and go 33's, or will that raise diesel consumption even more
should i source a set of 16in standard gq rims and run 16in tyres
should i stick with same size tyres i have

any suggestions appreciated ( btw 80% the car drives on tar and the odd trip up the beach)


Thats not all bad mate... I drive a 08 Hilux for work and it uses somewhere between 12-12.5lt/100km.
Anyway I'm with clunk71 on this one because I know i didn't buy my patrol for its fuel economy...

TuffTD42
23rd August 2011, 05:10 PM
By lifting your patrol you are now exposing more of the underside of the rig. You are now messing up the aerodynamics. This in turn will effect your fuel economy. I wouldn't of thought it would have made 2L/100 difference tho. The bigger the tyre diameter the more your fuel economy will suffer. You can change diff ratio's to help the power & fuel economy tho. I'm running 35's & 6" lift & getting anywhere from 12.5 to 13.4L/100.

Mrowka
24th August 2011, 02:39 AM
The other advantage of bigger tires is that they make big obstacles into littler obstacles.

dasemm
24th August 2011, 08:35 AM
I had 31's on 17' rims on the GU4,. but changed for 16" steel rims and 33's as a few years ago there was better availability of tyres for 16" rims in the bush. I never even considered fuel economy..

snake1978
24th August 2011, 12:34 PM
ive only had it a few mths, but it does have a new injector pump, and probably blows a little bit more black smoke under load than it should
some1 suggested that it may need the injector pump tuned to the motor as it could be runnin rich, hence the smoke and 13.5 litre/100 when it should be closer to 11

TuffTD42
25th August 2011, 04:33 PM
ive only had it a few mths, but it does have a new injector pump, and probably blows a little bit more black smoke under load than it should
some1 suggested that it may need the injector pump tuned to the motor as it could be runnin rich, hence the smoke and 13.5 litre/100 when it should be closer to 11

Now you mention the pump it could well be your issue. Or injectors. How's the air filter?

YNOT
25th August 2011, 04:46 PM
Now you mention the pump it could well be your issue. Or injectors. How's the air filter?

I agree, replace the air filter and see what that does.
Also check the small gauze filter inside the banjo bolt where the fuel inlet hose connects to the back of the injector pump, if this is blocked it can cause black smoke.

Tony

PS, we may need to change the title of the thread to "Snakes questions" because we've well and truly gone off the tyre topic!!!

Finly Owner
25th August 2011, 08:46 PM
Ok let me take it back to tyres:

Am I right in thinking;
That less revs turning small wheels will take longer to travel over the same distance than more revs turning bigger wheels? therefore, would balance out in fuel econony?


Tim

growler2058
26th August 2011, 05:54 AM
I think i get where ya comin from Tim, like a 10 speed racer you use less energy to travel faster so therefor the economy should be better