Better fuel economy and power.

[Powerful72]

Hi, I was wondering how I can improve fuel economy and power for my VP V6?
Can you get a chip for the ecu? Do you think the injectors need replacing? Is it ok to use E10 fuel or does this burn more fuel? Also is it possible to make some upgrades to change to E85 fuel or do you need to raise the compression of the motor first? I don't know much about this stuff but want to learn more so any advice will be much appreciated. I have had my VP for 12 yrs and it has been a great reliable car. It has 270k ks on it and I want to start doing some maintenance and upgrading. Thank You

 

[ephect]

generally economy and power dont go together, and normally you're after one or the other.

what currently do you get fuel wise km/l?

whats your budget for increasing power

 

[Powerful72]

I'm getting about 300 k's to a tank. I think the tank is about 60 L so that would be 5 ks/L. I'm mainly looking for a mild power increase and can spend about 1 k. The motor is getting a bit tired so I'm going to save for a ecotec but was just looking for ideas at the moment. I haven't had the car professionally serviced for about six years. Does the ecu go out of tune?

 

[VPRob]

What have YOU done by way of servicing if it hasn't been professionally serviced. We can't give much advice without knowing some history. 300kms per tank is not that good (depending on what sort of driving you are doing) but it would mean more if you observe how much you put in each time you fill up. I get 10 to 12 litres per 100 km and am not that happy at that. You seem to be using about twice that much fuel per 100km (5Ks per litre = 20 litres per 100km) suggesting that air filter, plugs and leads, CAS, coil packs, sensors (various but definitely O2 sensor) and other basics would likely be a good starting points.
If you want more specific suggestions we need more information.

 

[Dave6179]

Best exhaust you can find... horsepower doesn't have to be loud/obnoxious.
Rekit yer brake calipers, you may have a binding issue.
Our auto VN V6 Calais will do a 400km trip on half a tank.
I tried a SV3800 chip and it got lots better... made the other improvements work better.
Remove useless **** outa the boot/back floor, more weight means less fast.
Injector cleaner in the tank, new plugs, fresh air cleaner, handbrake off, less loud pedal. And yeh, test/replace the O2 sensor if it's stuffed.

 

[Immortality]

New O2 sensor. Check engine temp sensor and thermostat is working correctly.

Remove and clean the MAT (manifold air temp sensor). New fuel filter. Some injector cleaner, new air filter. plugs/leads?

 

[Powerful72]

Thank you all very much for your advice. Much apreciated. I will replace all those parts and let you know how I go. Should I just go to supercheap or is there a good quality supplier on the north side of Brisbane that would be better? I have a 2 and a half inch exhaust with the standard cast manifolds. Which are the best value for money extractors to get?

 

[Jxfwsf]

There is no point chasing power with the current fuel consumption.
300KM's to a tank is atrocious, waste of time putting a "chip" in it in this state, it's already not running correctly and this is just going to make it worse and harder to fault find.
E10 is probably ok but it's less powerful than petrol, needs more fuel to create the same power, the ecu is tuned to keep the afr for petrol so it'll be working off this so no gain.

You should be getting 450-500km(town) to 600+km(highway) to a tank, start with the basics plugs, leads, air filter and service.
Start hunting where the fuel is going, How old are these sensors:
o2 (Oxygen sensor in the exhaust)
mat (manifold air temperature)
cts (coolant temperature sensor)

How are the vapor lines near the tank and around the filler? if they haven't been replaced they'll be perished and cracked and need replacing (look in through the drivers rear wheel arch at the fuel tank, is it all stained around that area?).
Using any ethanol blend fuel with an unsealed fuel tank with vapor lines in this state is bad, ethanol will absorb moisture from the air so you'll end up with water in the fuel.

 

[Vp4ever]

I did all the fuel tank lines when I changed the pump & return hose(in the tank).
The biggest fuel consumption drain was the fuel pressure regulator leaking into the manifold. $20 part.
Check for vacuum leaks.
Tranny ok? Check torque converter locks up ~95km/h etc.
Oil change & filter improves milage.

I get factory 8L/100km country 10-12L/km city