OEM Header Mod ?

[MRBRZ1]

Should i digging the cat of header only or cat and frontpipe must?

For now i'm with miltek catback and inbox filter oft stage 1.
I checked and found that there is no more difference between uel and el header map for stage 2.

What is acceptable knock value and what should be the afr in case i will switch to stage 2 with modified header?

[churchx]

Header's cat is most hindering performance, as cat relatively close to cylinders (to heat up sooner to working tempsfor better coldstarts emissions) is far from optimum header design, especially runner lengths wise. Decatting frontpipe nets relatively little. Though if decatting header (for which ecu tune to fully extract performance from better scavenging and to disable cat readiness checks/CEL is more then beneficial), i'd consider aftermarket catless header for even more design improvements (such as larger diameter runners of length better optimizing curve) and for having stock catted header around if one might need it to pass some MOT emissions checks in future.

[MRBRZ1]

For sure the after market header is the way to go,the issue is that I can't get it in my country for now and trying to find the way to avoid the middle power dip somehow.

[churchx]

there are two good ways to avoid it, one, applicable to daily driving on public roads is to keep rpms below it to keep along traffic flow and for economy purposes, another, for track, to keep rpms in powerband above dip. Imho torque dip "issue" is waaaay too overblown. Also decatted stock header won't get rid of dip. For that is specific design of aftermarket headers (btw, not all of them).

[Tanstin]

I was actually looking into this a few weeks ago. Yes! This will net you approximately 80-90% gains of a typical EL header. Stock is surprisingly well built by toyota, with cats being the main restrictive component. Tune is needed to truly take advantage of it tough. You can buy an old stock header for $150, then get OFT Stage 2 EL for another $300 used.

Keep in mind, this isnt an ACE 350, so dont expect too much, but it'll definitely be noticeable in the torque dip rpm range

https://www.ft86club.com/forums/showthread.php?t=96235

Sent from my SM-G950U using Tapatalk

[MRBRZ1]

Does modified oem header will have CL?

[Contender]

Originally Posted by ramer.m@gmail.com

Does modified oem header will have CL?

Old thread but, I will reply like many here lol

If you tune then...No

[NoHaveMSG]

Originally Posted by ramer.m@gmail.com

Does modified oem header will have CL?

Yes. Unless you have a tune which eliminates the CEL for cat efficiency. P0420 is what needs disabled.

[MRBRZ1]

Thanks for your response

[nikitopo]

Pretty funny how many people are irritated with the mid torque dip. Looks most would be happier with a mild turbo and not having to drive the engine in higher RPMs. Each on its own merit.

[ROADRACER]

Originally Posted by nikitopo

Pretty funny how many people are irritated with the mid torque dip. Looks most would be happier with a mild turbo and not having to drive the engine in higher RPMs. Each on its own merit.

Its not like there is actually much power dip. If this "problem" wasn't posted about so often, I don't think anybody would even notice by how the car runs.