Here's my issue: I feel that my car doesn't pull as much and my gas mileage went down. On the highway it went from 7L / 100 km (33.6 mpg) to 8.2L / 100km (26.7 mpg).

Here's the changes I've done:

1) Tires went from the stock rosso's to BFG KDW2 225/40/18. I noticed that the pressure is between 28-30 psi so it's lower than it should be. The dealer didn't put enough pressure. So, i guess this doesn't help the gas mileage and the wider tires too. In terms of performance, it should slow me down a little cause the tire a bit wider.

2) Ingalls ETD - Shouldn't change anything right? Apart from vibs.

3) New spark plugs - Shouldn't affect performance / gas mileage? There's no knocking, it runs good.

Thanks for any input!

 

shorter tire.... maybe hell I dunno? Tire pressure does play a role as well, but also weather and temperature changes play havok with these cars!

 

Well...your tires are smaller...so your engine is turning 1.3ish% more rpms at 100km/hr.

the tires are also pretty low pressure...pump those to about 37-40psi and you will see a big difference - tire pressure really effects your rolling resistance on the highway.

Give it a shot and see what happens.

 

Yeah i'ill at least pump them to 32-25 psi around there and i'll probably see a big difference. At least i hope so.

Thanks!

 

i got like 10.9L/100km's, your doin fine.

 

I pumped my tires back to 34-35 psi and it improved significantly and my performance seems a lot better. I guess underinflated tires slow you down quite a bit.

Thanks!

 

maybe an oil change? just a guess... cause i know the fresher the oil the more mpg

 

1,000 km on the oil (that is 600 miles or so), so that's ok.

Everything seems ok now since I pumped up my tires to 34-35 psi. It's running like new!! Haha!