by chriscarter » Sun Oct 23, 2011 5:25 am
I'm not completely familiar with the OBX system, but if it replaces the converter with a straightpipe, you may have problems passing your next emissions test. Also, be aware that your car's ECU is programmed to know that a converter is in the system. The downstream (after the converter) oxygen sensor is calibrated to work within a converter system, so if you remove the converter, the O2 sensor won't be sending accurate signals back to the ECU. This could result in both poor driveability and higher emissions over the long run.
Sure, lotsa people have removed their converters with no ill effects, but with the parts that can be affected being so expensive, I like to leave the converter and install free-flow intake and rear muffler. For what it's worth, I have found that removing or modifying an engine's designed-in emissions equipment will result in longer-term driveability and higher emissions issues. If you do want to remove your converter, modify your injectors, or do something else to bypass your engine's emissions controls,...I would do those modifications that can be easily reversed and returned to stock when needed or wanted.
This does NOT necessarily apply to blower kits and other performance engineering that are specifically designed for your car. Usually, such systems are well engineered as long as they don't completely remove or bypass your emissions components. Increased performance is a balancing act...the relationship between having a faster car, that car's everyday driveability, fuel consumption, increased fun factor, usually more required service, exhaust emissions, and the cost of modifications all need to be considered.
Some people spend a bunch of money and end up with real driveabiltiy issues (bad cold start, lumpy idle, no lower end, etc.) in order to gain maybe a .2 (2 tenths of a second) 0-60 time on their everyday driver! The best performance modification anyone can do is learning how to drive better! Proper shifting technique, knowing the optimum RPM to shift, determining if you gain some time by manually shifting your automatic, using the best tire pressures for performance driving, using lower-friction synthetic lubricants, taking the 50 lbs of junk out of the trunk, and other common-sense tricks can gain you some time without spending much money at all.
Hope I'm not sounding like somebody's conservative uncle, but over the years I have modified many vehicles and engines. Installed one of the first turbos on a water-cooled VW in the early 1980s and my shop was one of the regional diagnostic and referral locations for Callaway Turbosystems for a couple years. The big takeaway here is that modifying for better performance and fun is great..........just don't do something that will cause you more grief than you expected. Think your project through during your planning and "I want it" stages.
So, Mr Wizzy - The short answer to your question is......yes and no! Do tons of research and decide which way you want to go.
Last edited by chriscarter on Sun Oct 23, 2011 10:25 am, edited 1 time in total.
