Fuel Problems

[VBSL79]

I was just like to know if anyone can help me with my VB Commodore drinking a **** load of fuel what is causeing this problem with my car and is there any way of fixing it ? I have gone to a 3.3 Blue engine and put a weber carby on my car and still got this problem

 

[chuck]

Whats the diff ratio ?

 

[VBSL79]

My Diff ratio is 2.78:1 it was 3.08:1 and its a Auto

 

[Jaws]

Changing the ratio from 3.08 to 2.78 will make a big difference especially when accelerating.
The trimatic is designed to use at least a 3.08 diff and using a lower ratio is making the gearbox and engine work much harder under accel. esp when taking off.

I have made the same mistake before too.

 

[VBSL79]

What would be a good diff for my car then ?

 

[jafo]

i know this sounds like a stupid comment but a good tune and service helps
heavy braking and acceleration also uses more fuel
and also check for leaks in the fuel system
my vb had a huge prob with leaks
there are lots of things that can cause exessive fuel usage to many to mention but ill list some that i know
rear brake ajusted to tight(dragging)
mixture to rich
timing out
carby set wrong
hey im no mechanic but they do use fuel

 

[chuck]

Diff ratio depends on what kind of driving you do for instance
>>3.36 good for city driving launching but uses more fuel on the highway

>>3.08 ideal cruising ratio (in my opinion anyway)

>>2.78 good for highway use but sucks in traffic as it uses more fuel stopping and starting all the time

>>2.60 you usually don't find this ratio in commodores but its really good for highway use but no good for anything else

You could go for a VK-VL borg warner diff

If iv'e missed any ratios just add them people.

 

[vlturbo]

You could use vl turbo diff with a ratio of 3.45

 

[Jaws]

VK series 2's use a 3.23 borg warner diff, any diff VB-VL will fit

 

[Grunter]

a vl turbo diff would probably be over kill and a bit pricey, he would possibly have to upgrade to use the disc rear as well. If your really after the 3.45 then the standard vl ones are 3.45 and still use drums, or like jaws said the vk borg warner diff

I got a Vk with the 3.23 diff and it sits on just over 2 grand in 5th on the freeway.