Exhaust Packing

Message

Tipper2 · #1 Post by **Tipper2** » Fri Apr 15, 2016 10:23 pm

Hi,

I've just started visiting here after posting on AF1 (and being invited a couple of years ago by Aladinsanuek- thanks) and picked up quite a bit of much appreciated info from reading back through old posts.

My build is almost done but the art titanium race cans cans I've got are too loud, a sure sign of old age (twenty years ago I'd have been trying to make them louder).

Has anyone tried Acusta-fil exhaust packing? It's supposed to expand when it heats up to get better sound absorption.

http://www.ebay.co.uk/itm/Acousta-Fil-E ... OSwaNBUfQ5~

Cheers.

#2 Post by **mangocrazy** » Sat Apr 16, 2016 8:27 am

Looks very interesting. I like the fact that it's quilted, which means it should be easier to use and should also last longer. But unfortunately the only way to know is to try. You could always call or email the seller and ask for more details. They might even be able to quote a db improvement figure if it's been properly tested.

Tipper2 · #3 Post by **Tipper2** » Sat Apr 16, 2016 4:55 pm

I'm away from home for the next week or two but plan on ordering some when I get home and measure my cans.

There's a db meter on my phone so will do before and after measurements to see what difference it makes.

#4 Post by **mangocrazy** » Sat Apr 16, 2016 8:03 pm

Sounds like a plan... Keep us posted.

Tipper2 · #5 Post by **Tipper2** » Tue May 03, 2016 7:00 pm

Opened my cans up today and found out why they where so loud- one of them had next to no packing! What little there was had gathered in an inch-wide ring in the end cap.

I used an app on my phone and got 94dB before re-packing and around 89dB after, definitely a noticeable improvement. Hardly surprising considering one of them was just an echo chamber.

The stuff was easy to use and came pre-cut. There's an online calculator to keep you right before ordering.

http://www.thermalvelocity.co.uk/calc/calculator2.html

It might drop a bit more once I (eventually) get out for a blast and get the cans up to a good temperature. I'd definitely use it again- much easier than the old fibreglass stuff.

#6 Post by **mangocrazy** » Tue May 03, 2016 7:03 pm

The db scale is logarithmic, so reducing from 94db to 91db would halve the sound pressure level. Reducing to 89db is close to making the SPL one quarter of what it was before. So quite a result...!

Tipper2 · #7 Post by **Tipper2** » Tue May 03, 2016 7:07 pm

It was measured using a phone app so more of an indication than a measurement but obviously much quieter than it was. I'm happy anyway!

#8 Post by **mangocrazy** » Tue May 03, 2016 7:10 pm

Yeah, not exactly laboratory kit, but a good indication. Nice work!