28 replies to this topic

[JG]

Matt, why don't you stick a standard bb on it, just to see what happens.

[smiley]

Matt, why don't you stick a standard bb on it, just to see what happens.

That's going to be interesting.
I struggeled major with my 2.5 tullet cat section fitting to anything 2" backbox, due to tullet u-bend not compatible at the flange.
Interesting to see how the 3" u-bend will do.

[Phear]

For the record my repacked tullet plus de-cat silencer made 90db at Keevil yesterday which I was well chuffed with. Granted that was only at 4200 not 4500rpm (I don't think the tester could see the rev counter properly). When I repacked my tullet I put less in than you have there. They sent me 2 bags of the stuff and I used just over 1.

[techieboy]

For the record my repacked tullet plus de-cat silencer made 90db at Keevil yesterday which I was well chuffed with. Granted that was only at 4200 not 4500rpm (I don't think the tester could see the rev counter properly).

When I repacked my tullet I put less in than you have there. They sent me 2 bags of the stuff and I used just over 1.

I get similar static readings. Static testing has never been an issue with this exhaust (unlike one or two of the Pipers, I had), it's drive-by's (and just driving full stop) that I struggle with, when the car is properly under load.

Reading everything I could about Acousta-Fil last night, there seems to be general consensus that the best density for the packing is somewhere between 130gsm and 150gsm. No idea what that looks like in regard to the number of layers but the calculators out there all seem to suggest something like a 2.6 metre length of it. That sounds like a lot to me.

Matt, why don't you stick a standard bb on it, just to see what happens.

Explosions.

[Mike (Cliffie)]

The drive by is more affected by the supercharger scream under load than exhaust. My new airfilter set up has really quashed that scream and I reckon I could do a Bedford day now.

[techieboy]

Yep, the fully enclosed filter setup I fitted for the National made a decent improvement. SC whine (on a stage 3 pulley at least) has definitely been knocked down a bit - seems to take a little bit longer before the whine comes in and it's definitely altered the character of the noise by filtering out some of the higher frequency noise and just generally sounds a bit more muted. Only problem with that is it's highlighted just how annoyingly sh!t the exhaust sounds.

[Kieran McC]

Are you using a 3inch Tullett system all the way from maifold to rear box? What Db readings does it give on static and driveby? Looking to replace mine still looking at different options

[Phear]

Are you using a 3inch Tullett system all the way from maifold to rear box? What Db readings does it give on static and driveby? Looking to replace mine still looking at different options

I am using a full 3" tullet system and as stated above got measured at 90db static. Haven't been anywhere that does driveby yet.

That is with a de-cat silencer though and it was probably 3-4db louder with a cat.

Edited by Phear, 17 July 2012 - 06:27 PM.

[techieboy]

Yes, full system, manifold all the way through. Unless you're trying to wring every last bit of power out of it, I wouldn't bother in it's current guise. It's annoyingly loud in regular use with a horrible grating drone and liable to get you black flagged at anywhere with a vaguely tight drive-by limit. Mine's currently at a local exhaust place for them to chop off the tailpipes and modify the tailpipe section for a single exit with an inch longer exit, so that I can reliably attach a db killer/baffle to it for places like Donington, Goodwood, Combe (still no hope of making it on track at Bedford, which is 10 minutes away). I'd be more inclined to stick with the 2.5" system, which is all that's really needed or better yet, replace your knackered Milltek with a Milltek turbo backbox.