Will the new gen benefit from aftermarket headers like the last gen did?

[rowen0fpts]

...or does what they did to fix the toque dip negate a header’s benefit?

Also, are aftermarket headers (catted specifically) something we’ll be able to do on the 2022 immediately? Or will it mess with our warranties? Thus making us have to wait.

[dragoontwo]

We won't really know until the products are developed, and are able to tune the ECU.

[Spuds]

It's a safe bet a less dense cat mesh will improve flow and therefore power.

[mazeroni]

You have to think about it from feel and on paper metrics.

The torque dip in Gen I is relatively bad because it is both deep and wide. It affected acceleration and the feel of the car so greatly. So flattening the torque curve even a little was noticeable both in the seat and on paper.

With Gen II, the dip exists, but the baseline torque is still better than peak torque in the GEN I engine, and it is narrower. The car feels and is fast in stock form. So flattening it further will likely improve performance on paper, but I doubt you will feel in from the seat in the same way.

If you want a header with Gen II, I'd look at it from a sound perspective primarily.

[rowen0fpts]

Originally Posted by mazeroni

You have to think about it from feel and on paper metrics.

The torque dip in Gen I is relatively bad because it is both deep and wide. It affected acceleration and the feel of the car so greatly. So flattening the torque curve even a little was noticeable both in the seat and on paper.

With Gen II, the dip exists, but the baseline torque is still better than peak torque in the GEN I engine, and it is narrower. The car feels and is fast in stock form. So flattening it further will likely improve performance on paper, but I doubt you will feel in from the seat in the same way.

If you want a header with Gen II, I'd look at it from a sound perspective primarily.

I should have been more specific. The sound is primarily what I would be after. Once I heard that the original TRD exhaust wasn’t going to be a factory option on this car, I think I’m going to go with the Perrin 2.5 res, but worry that without a header it’ll just be way too quiet and barely noticeable.

[OwlDance]

So I'm parroting what I read on these forums a while ago and drawing my conclusions hypothetically but basically it has to do with header runner lengths and exhaust scavenging etc.

A development article stated they were able to move the FA20 header catalyst a little bit backwards compared to the FB20 while maintaining identical warmup times to lengthen the headers.

The ace350 gets really good gains alongside the JDL421, each of which has long exhaust lengths, the former at least making a torque peak where the dip used to be.

With these two things in mind it's obvious to me that the torque dip is the result of the short OEM header lengths which are constrained by catalytic converter warmup times to meet emissions standards, of which is nullified by having a longer header and the removal of the header catalyst.


I doubt they've included any new fancy technologies to bypass header warmup times so in my opinion we should see roughly similar gains, probably slightly less in magnitude.