Ok, so I've got an '01 Honda Accord EX, 4 Banger, A/T and I was jsut wondering something. I know SULEV is to help the car fall under Californias emissions laws (I live in Cal) and I was jsut wondering if the added emission "care" if you will, will affect the VTEC itself, i.e. lose power v. a normal VTEC etc. Any help is greatly appreciated thanks alot!

 

I'm not sure how it affects the VTEC, but the ulev and sulev cut down a little on horsepower, a regular 4cyl Vtec has 150hp, a ULEV has 148hp and a SULEV has 145hp, and this info is from Honda's website.

 

The changes made to the pwoertrain ot attain ULEV and SULEV are mostly related to cost than specifically engine performance. A manufacturer might use a more expensive O2 sensor or multiple sensors to achieve tighter control o nteh air/fuel ratio. The second change is a more expensive and/or complex catalytic converter. Some Cat's cost more because they contain more of one or another perticular metal catalyst and may have a more restrictive design to achieve more complete conversion of certain emissions.

TO control manufacturing costs, I wouldn't expect there to be any mechanical changes to the VTEC. Only small changes to the fuel mapping or program.

 

You are correct sir. The SULEV has a much cleaner cat and has a special 'A/F Ratio Sensor' mounted in the front of the header as opposed to the regular O2 sensor mounted in the side of the head on ULEV models.

VTEC really has nothing to do with it.

 

I I remember right, the LEV2 Cat is already something Like $300 (OEM cost) ... but the ULEV Cat is almost twice that price. The sensor is also probably double the price as well. Clean air costs the industry billions of dollars, that why they lobby so hard against it. Most consumers don't consider those features ot be an added value, so MFG's avoid spending money on them.