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Discussion Starter #1
My SRT kit came with a high-flow cat on the downpipe and I am debating if I should just get a straight downpipe. This will be used with an iron cast manifold and not the long tubular type manifold.

So here they are:

High-flow Cat DP Pro:
quieter / cleaner?

Con:
bad air flow/might cause detonation?
__________________________________________________

Straight DP Pro:
better performance

Con:
louder?

I did however, heard from another member that made close to 400 rwhp with the HFC, but I was also told about troublesome tuning stories with the HFC dp.

My goal is close to 400 rwhp, so with 440 injectors, emanage, no fuel return, 2.5 HG, do you guys think I can achieve this goal with the HFC?

I don't want to bring the car to a shop for hours of tuning, but only to find that I need a new DP. I want it to be tuning ready when I bring it.

Share your experience and thoughts please.
 

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I thought doublins made about 400 rwhp on his SRT stage 2.5 kit. The only differences he had that I remember were a manual transmission and return fuel kit.
 

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Discussion Starter #3
so that makes it two. the person i had in mind before was alex. anyone else?
 

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Discussion Starter #4
SRT said if i remove all of the stuff inside the HFC then I will get a CEL. so either way, if i get a custom made dp or mod the current dp, i will always get a CEL. (what code would it throw?)

what do you guys think? and can tuning fix the CEL problem?

already asked SRT these questions and they are unsure.
 

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you will get a "cat efficiency below threshold bank 1 and 2" code

P04xx I forget.....

you can fix it by installing an o2 sim
 

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Discussion Starter #6
^ thanks. +rep

that should be easy to fix then.
 

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Why would you want a new downpipe ? If you want to remove a cat just cut it out and weld some piping in its place.
 
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