Exhaust manifold blowing

[Brunoandrade98]

So, my exhaust manifold has finally started to blow...

I haven't looked at it yet, but it will be likely the flexis. I can hear it blowing from the manifold, if I look underneath. Driveability hasn't changed much apart from the very occasional misfire while driving. I'd say it sounds like it's misfiring while it's idling but to be honest my 197 always sounded like that since I've owned it...

For me, the two realistic options (given the budget) is to either:

• Repair my own manifold / fit a repaired OEM one
• Fit a Toyosport de-cat manifold

Repairing my manifold or even fitting a good/repaired OEM one is a solid option, not too expensive and likely the winning option. However, I have a few questions in case I should consider a Toyosport manifold:

1. Would the car need to be remapped on a dyno or could it be remapped remotely? - who does that and how much would it cost, roughly?
2. How much louder does it make the exhaust? - does it sound much louder, drone-y or just downright shit?
3. How much power can you expect to gain from it? - if any...

Thanks in advance