[bjbonentte]

My main question is this. I have heard that you could take the primary O2's and put them behind the secondary cats and avoid check engine lights. Is there any truth to this.

I am not ready to tune the car just yet. I want to do flex fuel first before spending money on tune.

[Lemmy Camaro]

I do not recommend it. I did the same thing shortly before I got my first time done and looking at the tables the car ran into a serious lean condition. This can lead to burning out rings faster and can lead to some serious issues. Theoretically you can, it's just not great for the car. Especially if you plan on getting into that higher rev range. I'd recommend looking into a set of long tubes instead of cat deletes. Everyone I've seen including myself has always gone from cat deletes to a set of catted or catless long tubes. Saves you money on a retune if you ever decide to do so

[KingLT1]

Technically you can make it work as is by installing o2 "no foulers" and it will keep the CEL off but there is no power gain and you lose torque until the torque limits are addressed in the tune.

[TheRealJA105]

Originally Posted by KingLT1

Technically you can make it work as is by installing o2 "no foulers" and it will keep the CEL off but there is no power gain and you lose torque until the torque limits are addressed in the tune.

King can you explain why you lose torque and gain nothing in this case and what adjusting the torque limits does? This is probably why my car went slower at the strip this year than last year.

[Joshinator99]

Originally Posted by TheRealJA105

King can you explain why you lose torque and gain nothing in this case and what adjusting the torque limits does? This is probably why my car went slower at the strip this year than last year.

I won’t steal King’s thunder as he knows these cars very well, but in a nutshell the E92/E92A ECMs are torque-based. The ECM uses these torque values to calculate (and then measure) the required airflow to hit the torque targets. If you mod your car without tuning, the car will retard spark or close your throttle to keep the torque numbers in line with what it’s expecting to see. So outside of a catback, some cold air intakes, and maybe a ported TB, you need to plan on tuning to go with your mods. If a mod doesn’t need a tune, it’s because it’s not doing much for you...

[KingLT1]

^Spot on.

[bjbonentte]

Thanks guys. I have opted to wait on the exhaust and get a tune and e-85 first. I have have cold air, ported TB, and LT2 so e85 and tune would make a pretty killer combo. Add long tubes later and should be good to go.

[TheRealJA105]

Originally Posted by Joshinator99

I won’t steal King’s thunder as he knows these cars very well, but in a nutshell the E92/E92A ECMs are torque-based. The ECM uses these torque values to calculate (and then measure) the required airflow to hit the torque targets. If you mod your car without tuning, the car will retard spark or close your throttle to keep the torque numbers in line with what it’s expecting to see. So outside of a catback, some cold air intakes, and maybe a ported TB, you need to plan on tuning to go with your mods. If a mod doesn’t need a tune, it’s because it’s not doing much for you...

Originally Posted by KingLT1

^Spot on.

Thanks guys. My car is supercharged and i did the cat deletes because i thought my cats were melting down on the road course, but it turned out to be another issue. I run the anti-foulers and not having the cats seems like it should help with the exhaust heat on the road course. Do you think I am slowing the car down and not actually helping with heat?

[KingLT1]

It should be helping.

[TheRealJA105]

Originally Posted by KingLT1

It should be helping.

But could have also slowed my 1/4 mile?

[Joshinator99]

Originally Posted by TheRealJA105

Thanks guys. My car is supercharged and i did the cat deletes because i thought my cats were melting down on the road course, but it turned out to be another issue. I run the anti-foulers and not having the cats seems like it should help with the exhaust heat on the road course. Do you think I am slowing the car down and not actually helping with heat?

Originally Posted by KingLT1

It should be helping.

Originally Posted by TheRealJA105

But could have also slowed my 1/4 mile?

Not knowing anything about your combo, I definitely agree with King. On a supercharged car, the primary cats become even more of a restriction than when you’re stock. Taking them out will not slow your 1/4 mile... no way.