Back pressure causing misfires from Stage 1 remap

[galaxie500]

https://www.youtube.com/watch?v=phmlSQ9zhnY

Interesting video from a German tuning Shop. On one hand it seems very plausible that the manifolds are restrictive. On the other, I haven't read any reports of misfires from stage 1 remaps on here. Is he talking sense or up-selling his £3k racing manifolds?

I want to keep my car for a long time and was considering a remap but going by his advice the minimum for longevity would be some form of upgraded charge cooling, manifolds and exhaust. It does seem daft upgrading the exhaust and not doing the manifolds but there doesn't look to be a solution yet for charge cooling?

EDIT- just watched again, it's not completely clear but back pressure may just be a problem with bigger turbos?

[Tadass910]

Better if you change exhaust to cattles for more free flow, for example Miltek none resonated exhaust and leave stock Downpipes, instead of leaving stock exhaust and adding cat less Downpipes, then you will face real back pressure, or for example Akrapovic which has more restrictions than Miltek none resonated exhaust, for best flow would be cattles Downpipes + none resonated exhaust. But I think none resonated exhaust + stock Downpipes doesn’t do much back pressure

[Paulm]

2 trains of thought here. after you do the plugs and coils etc

1. There was a tech bulletin issues around valve springs causing a misfire
2. Oil scraper ring sticking causing a misfire

My RS6 stage one with milltek did it as did my RS7 stage one. both 2015 cars. reducing torque midrange more or less fixed it. I say midrange it was around 5500rpm my cars misfired.