engine tune and exhaust sound

[stigmundfreud]

Now I am more than aware of the difference in sound that different components can give. I know that often people say the Wortec has a raspy sound, more ferrari than say the miltek and its more traditional sound.

As I've been reworking my tune getting things dialed in the exhaust note has changed notably (not majorly) and I wonder just how much of the noise is also down to the actual timing and ve maps?

[ringram]

Quite a bit actually. You can hear the difference. In effect more exhaust pressure is created with timing more optimal as expansion is greater and power increases. Retarded timing means lower cylinder pressure and IMO a less "angry" exhaust sound. Thats how I know Im getting close with the tune because the exhaust sounds harder and sharper. Mind you compared to timing found on the dyno road tuning is way off the mark.

[anonymous-user]

does that mean my car will sound more "angry" when I add the supercharger?

[ringram]

If you get the timing and exhaust right Im sure it will, Im not exactly sure why it sounds angrier, but timing will certainly increase cylinder pressures when optmised

Edited by ringram on Monday 20th August 14:01

[stigmundfreud]

I am getting very little knock with the hsv timing map. Are you saying that on the dyno I can tune that even harder? There is lot of areas I feel I could add timing to and then monitor - what is your prescribed way of adjusting the timing?

[stigmundfreud]

another question, just how big a part does the exhaust note depend on the actual exhaust tip? Obviously I know that if you play a trumpet the bigger the horn the deeper the sound. The Miltek tip is like the Mersey tunnel whereas I notice the Wortec (5.7 single exit) systems use two smaller tips.

Does the exhaust tip really play a big part? After looking under mine and anothers car its hard to see any real differences as to this - I am guessing the tip does play a part? Where can I get different tips from as I can unbolt mine I figured it would be good to try different tips