no cat, detune?
#11
#12
#13
04 5.7, cammed, long tube headers, no cats, no resonators, runs fine, no torque loss, kills prius owners all day.
How many of you have ever looked to see whats in a cat? Nothing in it increases back pressure, makes more power or anything else. There are screens in it with certain rare metals that react with the gases in the exhaust and basically "filter" it. This why is smells bad without them versus with them
You arent going to loose power or torque.
Although I am custom tuned, I have non-foulers (see the FAQ/DIY secton) on my rear O2s to trick the PCM into thinking the cats are there because the PCM uses the front O2s to read AFR and make adjustments as needed. The cat filters the exh gas and the PCM reads the rear O2s to read the difference in the front to rear O2s and to make sure the rear O2s are working properly. Thus the reason when you remove the cat you need to use non-foulers to bring the rear O2s away from the exh stream to force it to read a difference from the front O2s and make the PCM "think" the cat is still there.
How many of you have ever looked to see whats in a cat? Nothing in it increases back pressure, makes more power or anything else. There are screens in it with certain rare metals that react with the gases in the exhaust and basically "filter" it. This why is smells bad without them versus with them
You arent going to loose power or torque.
Although I am custom tuned, I have non-foulers (see the FAQ/DIY secton) on my rear O2s to trick the PCM into thinking the cats are there because the PCM uses the front O2s to read AFR and make adjustments as needed. The cat filters the exh gas and the PCM reads the rear O2s to read the difference in the front to rear O2s and to make sure the rear O2s are working properly. Thus the reason when you remove the cat you need to use non-foulers to bring the rear O2s away from the exh stream to force it to read a difference from the front O2s and make the PCM "think" the cat is still there.
#14
Even if you don't have e missions testing where you live,there is still a good chance that you'll get caught. Cops/highway patrol have full right to check the e missions equiptment on your vehicle if they feel the need to do so. It happened to a buddy of mine.he got pulled over for highbreaming a cop. The cop looked under his truck that had no cats and BAM!.... Impounded truck and $ 5000 fine. And no we don't have emmisions testing here c
#15
#16
Apparently ''gutting' the cats can be done- I heard of a guy i worked with that has done this (can't remember the vehicle) and it has worked- he just cut open the top of the cat- gutted it and then welded it back up, and never hooked up any non-foulers... any body else hear about doing this?
#20
make sure to pull the oxygen sensors before you go trying to knock the guts out of a cat, you will ruin the ox sensors otherwise.. and as Weed says if a cat is not plugged or fouled it should not make more "back preassure" but with out the platnuim to change the NOx coming through the rear ox sensor will not see the change and through a code assuming the cat is bad..
PS the foulers will tip off a good inspector that you have gutted the cat also..
PS the foulers will tip off a good inspector that you have gutted the cat also..