Greetings - About 50, 000 miles ago I decided to try running my 93 1.8 l Acura Integra LS in a 12 valve configuration; one intake and two exhaust valves operational. What I did was simply loosened the valve adjuster on one intake valve for each cylinder. I had concerns that perhaps i might imbalance the cam shaft tower bearings and cause wear but so far nothing like that has occurred.
This improves gas millage for several reasons. First -It takes less energy to operate 4 less intake valves. Then you get better mixing due to the cyclone effect from the now off set intake induction. You also get better gas scavenging due to the ratio of intake and exhaust valves. Simply put the top end performance was sacrificed for economy.
Honda with advanced VTEC runs a 12 valve configuration in the economy mode; Also 2 exhaust and 1 intake valve designs were tried for racing around 1910.
The car has plenty of power and can still drive at 90 mph but what is the point these days ?
What did happen is that the engine makes additional noise due to the wide open clearances of the valve lash -- Some people think I have a diesel Acura due to the increased noise level and sound. Again I have driven this car for at least fifty thousand miles this way with out problems.
Colorado emissions testing before and after showed an immediate 49 percent drop in hydro carbons after the modification.
Recently I started using 0-30 mobile synthetic oil - Now all I need is a dyno and a real accurate emissions testing setup because i bet with proper tuning I could get an easy 40 MPG with a 1.8 L -
I am currently working on ozone injection -Any one know what an extra oxygen molecule or two does to the combustion and emissions process ??????