Are Headers Do-Able For Street This Way?

[Homeboy981]

Thanks to @The Radium King for this comment, which should shed some light on an exhaustive problem:

"each bank of 3 cyls has: headers - o2 #1 - precat - 02 #2 - mid pipe - secondary cat - muffler.

purposes are:

o2#1 - ecu uses to set fuel trims.

precat - only found on north american cars with tougher emmission standards. required only for start-up emissions (like the secondary air injection pump) the precat is designed to warm up quickly before the main cats get working.

02 #2 - used by ecu to check to see that the precat is working. again, only found on north american cars. can be fooled with minicats or spark plug anti-foulers. some guys get a 'rest of world' (row) base flash that doesn't look for the o2 #2 (also allows you to delete the secondary air injection pump and start the car without the clutch in, but will not pass obd emissions testing). others get a tune of their north american base flash that tweaks the o2 levels being sensed by o2#2 so that it passes emmissions without cats.

secondary cat - this is the main cat for the car.

exhaust, like intakes, wants to move as much air as possible at high rpm, but benefits from the back pressure caused by decreasing diameter piping, cats and muffler at lower rpm - your decision based on how you drive. raby says that one of the best mods for the $ is a cheap set of headers. this makes sense to me, as i'd rather have my restrictions further downstream (ie the mid pipes instead of the headers) to allow flow to establish itself.

fortunately no emissions testing where i am from. if you just have to pass obd, then going catless with the spark plug anti-foulers should work. if you have to pass visual, there are techniques to gut your cats that might work."

TRK not only does math well, also explanations….so I thought I would share.

Please feel free to elaborate on ANY ideas at this point. Headers were SUPPOSED to be my Christmas present - would HATE to get a TV or something….

Thanks for EVERYONE's opinion!!!

[tony_fury]

Originally Posted by Homeboy981

Please feel free to elaborate on ANY ideas at this point. Headers were SUPPOSED to be my Christmas present - would HATE to get a TV or something….

Thanks for EVERYONE's opinion!!!

Do you have the Durumetric software and cable?
That could be your Xmas replacement..
T

[Homeboy981]

Originally Posted by tony_fury

Do you have the Durumetric software and cable?
That could be your Xmas replacement..
T

Hey T,

Yes. That is next! We are planning a 'group buy' for the software and Durametric software that allows changes. For now I have borrowed, thanks to @Kenny Boxster, the 'read only' version of software to check my numbers on the intake.

The FULL writeable software is close to a grand (more than my Christmas budget for a tree and all)…..unless SOMEONE else has a source for it?

[Topless]

Definitely not "Smog legal" in Calif. It might pass an inspection by someone who doesn't look at em but the CHP won't let it fly. No knowledge of TX smog rules for street legal cars.

From CARB:

"A. Catalytic converter falls under California anti-tampering law. The law is designed to prevent tampering with pollution control devices on California vehicles. The anti-tampering law is Vehicle Code Section 27156 and covers all pollution related systems and devices on a motor vehicle. A violation of this law may also include a parallel violation of California Business and Professions Code Sections 17200 and 17500. Judges usually impose penalty based on the severity of the offence and whether a repeat offender is involved, and a fine of up to $2,500 for each violation may be assessed, as well as some jail time."