Please urgent! - valves

[daspei]

Hi guys, I have no knowledge about cars at all, but I would like to know if toyota corolla and toyota carina ('91 and '93) can get changed their 16 valves into 12 valves?

Is it true that with 16 valves those cars use more benzin (gas)?



Thank you

[Deep]

You could, but there wouldn't really be a benefit in terms of gas mileage or performance. Technically speaking, 16V engines are more efficient so they should get better mileage. I'm gonna assume that the car you're looking at has either 4AFE or 7AFE, which were designed for decent HP and good low end torque along with great fuel economy. You'd be best served to leave it alone.

If you want to learn more about engines in general, check www.howstuffworks.com , its a great site.

[Toysrme]

All that will happen is the motor wil be reduced in power.

In laymen's terms to get to X speed still requires the same amount of power. So you'll just wind up pushing the pedal harder.
Stick with the 16v's. It's more effecient. Make sure you do all maintinance on the car, and that it is in good order (if you have mpg problems).


The most important thing is to have a high economy driving style.

[daspei]

Okay, thanks!

So basically that means that by changing 16valves to 12valves wouldnt save gas?

Meaning that 16v really don't use much more gas from 12v or if it does that diff is so small that is irrelevant?!

[amerikim]

16 Valves was so they could get more valve space in combustion chamber and better flow. It is more efficient, therefore burns less to produce more. If you went from the same capacity engine, you dont want the 12 valve.