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Maxlean
11-15-2023, 06:23 AM
Firstly, I want to thank Steveo for his amazing work with EEhack and all the other utilities and information that helps make $EE tuning so fun and easy. My question is really for Steve. His site, ecmhack, has a page about specific adjustments that are generally made for long tube headers pertaining to the relocation of the o2 sensors. Well, this page appears to have broken links for images where he is demonstrating what adjustments should be made. Steve, can you fix the example images or perhaps post them here?
Thanks
Scott

steveo
11-15-2023, 06:51 AM
hey there
well the pictures are gone, i never noticed!
i moved the site and lots of stuff broke
anyway there's the O2 INT DELAY - MV ERROR and the O2 INT DELAY - AIRFLOW tables.
one is vs airflow one is vs 02 mv
i would take the airflow table, which is in ms, and wildly ballpark out how much longer the exhaust gasses will take to reach the o2 than the original manifold.
if your header primaries or collectors are larger, that makes things take longer.
if your o2s are further back, also makes things take longer.
you can't calculate fluid dynamics with high precision since you aren't a physisist so i'd be like 'hey, o2 sensors are about twice as far away as stock' and just double the delay times.

steveo
11-15-2023, 06:52 AM
oh another point is a longer delay is less harmful than a short one. lots of people have shown than through experimentation. so if you are unsure set the value higher not lower

Maxlean
11-15-2023, 07:16 AM
Thank you for the quick response! So the majority of change is to the airflow table? When does the mv table come in? I've got a Y body that has long tubes that have the sensors in the collectors, of course, but do not use o2 wiring extensions. The original sensor pigtail length and harness side are all stock, so I'm guessing the mv table can be left alone in my case?
Scott

steveo
11-15-2023, 02:14 PM
i would increase the delays a bit
the time it would take for the exhaust gas to reach the o2 is definitely longer with long tubes