[allan]

I have a 91 sierra stock 1.3 motor rebuilt with new 32/36 Webber it is using 13ltrs plus per 100ks it has 31x10.5 ats what could be problem no leaks all vacuum hoses correct please help. ???

[atari4x4]

have you accounted for the % difference in kms covered due to the larger sized tyres?

[Reubs]

allan wrote:

I have a 91 sierra stock 1.3 motor rebuilt with new 32/36 Webber it is using 13ltrs plus per 100ks it has 31x10.5 ats what could be problem no leaks all vacuum hoses correct please help. ???

No problem at all. Sounds pretty normal for a Sierra with 31s and a thirsty carby...

Got reduction gears at least?

[allan]

No I haven't what would be the % I need to add would you no

[JrZook]

31"/26.3" (stock tire diameter) = ~1.18 thus 18% oversized. Therefore you are using 13ltrs+/118km which is actually 11ltrs+/100km. Not bad at all

[allan]

Thanks for help everone would exhaust and headers help and can I play with the jets. Any info or recommendations i would be very greatfull.

[stockman]

Get some reduction gears before you do any thing else.

[norcorider]

stockman wrote:

Get some reduction gears before you do any thing else.

X2

powers not substitute for gearing.

[Gwagensteve]

norcorider wrote:

stockman wrote:

Get some reduction gears before you do any thing else.

X2

powers not substitute for gearing.

X eleventy.

[Cammopricey]

Have 31s on my sierra and it does use more fuel but not much and it does 130kmh now not 100 flat out and revs abit lower

[spinach]

yeah same here, i got 31s. Sits at 2300rpm at 100kmh, and the whole time im having to drop back down to 4th. Does get annoying! Reductions the way to go

[KEENSY85]

Wow really good considering the tyre size, trust these guys about gearing mate the small changes will help ur cause running the large tyres, but not enough unfortunately I to thought this once , ur options will be unfortunately buy gearing and have them fitted/fit them your self or run smaller tyres on road and rev it up off road and ring her neck, wich will work but isn't the best idea, I just never used 5th gear in my last suzuki I could pull 130kmh too with the wind behind me, and my heart in my throat every bump felt like my last really dangerous shirt

[Cammopricey]

The day i got 130 was a calm day on a flat and go into 5th a true 100(85 speedo) was singin

[Gwagensteve]

Cammo, it's pretty hard to understand your posts. I'm not really sure what you're saying at all. Are you claiming your car has a higher top speed with 31's on it? Are you claiming it's better with 31's than with stock tyres? If so, better how? Because it goes faster?

You're changing from 4th to 5th at 85 km/h with stock tyres or 100km/h now the 31's are on. What of it?

Steve.

[Cammopricey]

The car is going 100 on my gps at 85 on the speedo and it does lose power but for high crusing in rural areas 1 hour+ i find it beter and in the bush i use 1st high great speed

[Cammopricey]

As i say better, less revs for more speed as i hate revving it at 4000rpm for an hour or more as it cant be good for a small car

[Joshyboy26]

no way they love revving. i sit on 4000-4100 for hours.

they just dont have the nurrys to pull at lower revs.
i find around 4g seems to be the sweet spot for being able to hold 100 in most situations and not revving a ridiculous amount

[Reubs]

Joshyboy26 wrote:

no way they love revving. i sit on 4000-4100 for hours.

X2 - the things a Sierra - not a friggen bombadore!