Outer Limits 4x4 Board

i have just re booted the my feroza with a set of toyo opats 225x75x15 replacing 205x65x15 car tyres.

great for off road now, but for some strange reason my fuel consumption has gone up.

100 kph was about 3900 rpm with the old tyres and the new ones about 3600 . so to me this should mean less consuption

any takers on why this is so


maverick

Hi. How did you work out the revs had changed at 100km/h- GPS or something? Because unless you've had the speedo recalibrated the reading at 100km/h won't have changed; your speed will though of course.

Reducing the revs can detrimental to fuel economy as the engine (although revving less) may be working harder to maintain the same speed. Manufacturers generaly set their vehicles up from the factory for the best balance between revs / performance and fuel economy.

Being a smallish four cylinder engine the Feroza needs to rev a bit at 100km/h in order to maintain speed. Larger engines have more torque at low revs and can handle higher gearing (ie. lower revs) without adversely affecting fuel economy.

I saw this in a mag the other day about factory 4wd, did have a roza spec in it, not much but..

it said "city driving... 9.5L/100km" "highway driving..... 6.0L/100km

Hope it helps ya out a bit

Those specs are BS there is another thread on fuel consumption and average i would say is 10km per liter or more

Maverick wrote:i have just re booted the my feroza with a set of toyo opats 225x75x15 replacing 205x65x15 car tyres.

great for off road now, but for some strange reason my fuel consumption has gone up.

100 kph was about 3900 rpm with the old tyres and the new ones about 3600 . so to me this should mean less consuption

any takers on why this is so


maverick

How many km's to a tank of fuel were you getting before the bigger rubber and what do u get now

RobF300 wrote:Those specs are BS there is another thread on fuel consumption and average i would say is 10km per liter or more

I agree
The best I have got in mine is 9L/100km and average would be about 10L/100km

shezzbeav wrote:I saw this in a mag the other day about factory 4wd, did have a roza spec in it, not much but..

it said "city driving... 9.5L/100km" "highway driving..... 6.0L/100km

Hope it helps ya out a bit

6l/100k highway yeah right mine used to drink it at 110 revving at 4k. Maybe they were doing 30 on the highway

The city one seems fair i guess

500 ks ususally just poking to work and back , now its about 450 interestingly enough ive only gone wider and back to the correct size so i assumed the fuel economy would get better not worse

maybe more grip

Maverick wrote:i have just re booted the my feroza with a set of toyo opats 225x75x15 replacing 205x65x15 car tyres.


maverick

Are you serious 205/65r15 is to small for a feroza

And 225/75 is too big! Standard size is 225/70.

Your sidewall height has gone from 133.25mm to 168.5mm. Standard height with 225/70 is 157.5mm.

You didn't mention how you were checking your speed vs revs and distance covered? If you haven't had your speedo/ odometer recalibrated then all the figures you've been quoting will be out. With the old 205/65 you will have been actually travelling a lot less km than the odometer reads; and with the 225/75 you will travelling further than the odometer reads. So your fuel economy may not be worse at all!?

Maverick wrote:500 ks ususally just poking to work and back , now its about 450 interestingly enough ive only gone wider and back to the correct size so i assumed the fuel economy would get better not worse

maybe more grip

geez thats good im only getting 300-350km out of a tank depending on driving style with 235/75/15 muds

[quote="shezzbeav"]I saw this in a mag the other day about factory 4wd, did have a roza spec in it, not much but..

it said "city driving... 9.5L/100km" "highway driving..... 6.0L/100km

Hope it helps ya out a bit[/quote

Looks su to me ainnt these figures the wrong way around, cause u dont have to keep accelerating on the highway. My zuk wif weber carb sitting on 100 (true) without a head or tail wind will get 11k's/l. Thats with 235/75 on 40psi

isn't standard 215/70..

cause i went upto a 225/75, which means i have gone up 2 sizes in profile.. 1 for the width increasing the profile, and 1 for increasing the profile from 70 to 75.

most likely the cause of my bad economy..

i'm seeing about 400k's to 47 litres
last tank was 385 out of 46.5 litres.

But that was city type driving, and only a sting from deer park to reservoir when I filled her up.

I wanna get upto 60 litres in the tank, which i believe it what it should hold...

225/70 is standard- look on the placard in the glove box.

You're getting around 11.75 l /100km ; I'm getting around 10.5 with 235/70 tyres and running BP 98.

is yours EFI??

I just went and double checked... 235/75

dunno why I thought 225... must have mixed up what I had with what was std... I'm running the same size as you Murcod.

I generally run either 95 oct premium or reg unleaded.

JrZook all Aussie model Ferozas are EFi.

Dan, your tyres are bigger by about 20mm diam- mine are 235/70. So your speedo will be reading lower KM than you've actually travelled too.

after 2 weeks of fuel consumption tests yup i'm getting 10 litres per 100 and my speedo is about 4 ks out on the high side according to my navman (gps) at 100 ks

any way all is well


thanks guys

After reading this I'm sure my motors farked!

I get 12l/100km at a best

uses a litre of oil a week and pings its tits off on normal ULP. Gotta love it. I bought this bloody car so I wouldnt have engine problems. Might as well have kept the turbo

Cheers
Brad

Rb: I hear ya...

$1800 on head and bits, and still burning oil like a mofo... could have just got it replaced for the money... And the economy does stink for a 1.6L *sighs*