[Ub2slow335i]

I recently removed my exhaust and resonator from my car. It sounds good but I feel I lost low end power how can I solve this but keep the sound? Oh I have afe dual cone and Cobb as well

[idrift4wd]

i have a feeling that you need some sort of back pressure to regain that torque back, but a turbo car there really isnt back pressure. maybe its in your head?

[rader1]

Originally Posted by idrift4wd

i have a feeling that you need some sort of back pressure to regain that torque back, but a turbo car there really isnt back pressure. maybe its in your head?

No sir, back pressure does not help torque. It hurts performance in every way. Exhaust velocity is what helps torque in the lower rev range.

Since we have turbos they are going to be the big restriction in the exhaust and what we do post turbo isn't going to have the same influence on flow as it would on a non turbo car. However, full catless has shown to have some HP gains.


OP, Its all in your head.

[Ub2slow335i]

Thats what I was thinking. It's not in my head fully I did a data log before and after and it did effect it. I might throw on some resonators and see if that helps.

[rader1]

Originally Posted by Ub2slow335i

Thats what I was thinking. It's not in my head fully I did a data log before and after and it did effect it. I might throw on some resonators and see if that helps.

Mind posting the logs? I'm curious as to what the difference would be

[Ub2slow335i]

I will when I get home

[Ub2slow335i]

Car def seems boggish down low and around 5k u def feel it take off

[bulldog_yyc]

ECU may need some adaptation time....

[Ub2slow335i]

Ive gone thru a tank of gas since install idk how long it takes

[benzy89]

If you're looking to speed up adaptation, you've got 1 of 2 options:

1. Find someone with BT software & ask them to reset your adaptation values
2. Unplug your battery (it'll reset the DME adaptation values). Next time you start the car it'll start on a clean slate

[ksalih]

Originally Posted by benzy89

If you're looking to speed up adaptation, you've got 1 of 2 options:

1. Find someone with BT software & ask them to reset your adaptation values
2. Unplug your battery (it'll reset the DME adaptation values). Next time you start the car it'll start on a clean slate

shouldn't this be done on every mod then? ...dp...dci...tune..?

[benzy89]

Originally Posted by ksalih

shouldn't this be done on every mod then? ...dp...dci...tune..?

Exhaust modifications (DPs specifically) seem to be the biggest shock to the DME b/c of the o2 sensors. A catless system usually throws a wrench into the system b/c of the emissions the car starts trying to make "trimming corrections" (the specific fault code wording), which then can cause misfires/limp mode/decrease in power.

[ksalih]

Originally Posted by benzy89

Exhaust modifications (DPs specifically) seem to be the biggest shock to the DME b/c of the o2 sensors. A catless system usually throws a wrench into the system b/c of the emissions the car starts trying to make "trimming corrections" (the specific fault code wording), which then can cause misfires/limp mode/decrease in power.

in that case I should have reset the dme by unplugging the battery post dp install? if this is what you're saying...then I need to get on that. sorry for taking over OP

[benzy89]

If you're not getting a CEL/SES light, misfires or any lambda bank/emissions-related codes + your logs are good, then you're fine. Some people (myself most recently) get lambda bank fault codes when they install DPs, which like I said then triggers misfires. At that point, reseting your adaptations would be a good place to start.

[Ub2slow335i]

But can't I reset those with my Cobb unit ?

[benzy89]

There is a reset option on the AP, but I'm not sure if that goes as in depth as reseting the adaptations.

[Rob1796]

Originally Posted by rader1

No sir, back pressure does not help torque. It hurts performance in every way. Exhaust velocity is what helps torque in the lower rev range.

^QFT. For years I've been trying to explain to people that backpressure is always bad, NA or FI, and that the key is exhaust gas velocity.

[Ub2slow335i]

So what should I do to fix my problem of Low end power loss. It def with out a doubt doesn't kick like it did before around 3k it does higher around 5k.

[lee.minwoo_]

I have a similar problem! I've installed my Catless Downpipes prior to my freeflow exhaust, and the power difference is amazing! Until I installed my full exhaust, everything seems boggish as well, as if "hollow" or "loose" power engagement. Anything else I Could do besides unplugging the battery? That is because I've programmed my LED amber lights off and all, so I don't want everything to reset~