Exhaust packing for IVA

[KevinW]

I made baffles for my sidepipes : 5mm steel rod from B&Q and 3 half moons welded on pushed into the baffle pipe, one mounted each end facing up and one in the middle facing down to force the exhaust gases into an S-shape rather than flowing straight through. Dramatically reduced noise. They are still in as it keeps my neighbours a bit happier.

I lost a few horses doing this, bu I don't really care, as I have more than I need for my driving ability.

[GazRichards]

Hi guys, I just thought I'd share some info.
I got my Dax through IVA last Wednesday after a few minors on my first submission.

This post is about noise.

I have a 1977 SBC with open side pipes which, having no idea how loud it was, I originally filled with 50g each of fibre wadding.

This setup failed IVA at 101 dB.

I repacked each pipe with 200g of wadding and sailed through at 88dB.

It sounds awful, way too quiet, but it passed.

The examiner said 100g would have been enough, so now it's passed, I'm taking 100g out and will report back on dB measurement.