just a vtec question

[Z0_o6]

People put cardboard over half the radiator when they have an upgraded cooling system and the car won't get up to operating temp in cooler weather. It won't help gas mileage any.

As Emmino stated, VTEC is either functional, or not. There is no "harder hit" or anything like that. Anyone who tells you there is, is full of shit. VTEC can SEEM to be more aggressive when you change the engagement point because the disparity between the two cam profiles is larger, but the performance will remain the same, you just may be able to get a little more midrange performance by lowering the engagement point when tuned on a dyno.

[Meatball546]

People put cardboard over half the radiator when they have an upgraded cooling system and the car won't get up to operating temp in cooler weather. It won't help gas mileage any.

If an upgraded cooling system is keeping the engine below operating temperature, something is wrong- most likely the thermostat. You could have a giant radiator and giant radiator fans, but the thermostat only circulates coolant through it when the engine needs to be cooled.

[Z0_o6]

If an upgraded cooling system is keeping the engine below operating temperature, something is wrong- most likely the thermostat. You could have a giant radiator and giant radiator fans, but the thermostat only circulates coolant through it when the engine needs to be cooled.

The fact is, that when you have an upgraded cooling system, in cool weather, the engine can't get up to operating temp for the thermostat to work in a reasonable amount of time. If you put cardboard over half the radiator, the car will reach operating temperature faster, allowing you to have heat faster, and the car to run at it's most efficient temperature range faster as well.

[Meatball546]

The fact is, that when you have an upgraded cooling system, in cool weather, the engine can't get up to operating temp for the thermostat to work in a reasonable amount of time. If you put cardboard over half the radiator, the car will reach operating temperature faster, allowing you to have heat faster, and the car to run at it's most efficient temperature range faster as well.

If you're running an incorrect thermostat, then that would happen. But if you're running the right thermostat, it only opens at operating temperature. When the engine is cold and the thermostat is cold, the coolant still circulates through the engine, but it just bypasses the route through the radiator because it doesn't need cooling. Even with a hugely upgraded cooling system, the engine is going to heat up just as quickly as it would with the stock system.

Putting cardboard over the radiator to block airflow is just restricting its cooling capacity. You're not going to increase the engine's operating temperature or make the engine reach operating temperature more quickly by blocking the radiator. It's all down the the thermostat.