[BTCC] Question on supertouring/S2000 engines

[Sodemo]

Ever since I started to go to touring car races i've always loved the sound of the naturally aspirated cars. The cars seem to have two distinctive sounds. One is a "buzzing/growling" engine note, and the second is an exhaust note.

A video to illustrate...
http://www.youtube.com/watch?v=cg-VYT01vnk
0:16-0:22
1:16-1:19
At the above timecodes you can hear a very distinctive engine type noise (there are more throughout the video, I have just listed these above as two examples). It seems as though these cars make this noise as they are moving towards you, or the camera, and when they are moving away from you or a camera, this noise becomes the exhaust note.

Another video...
http://www.youtube.com/watch?v=1Lt1PkMZrCM
0:28-0:33

I guess my question is really; what is done to these engines to make them sound like this. Is it a specific part which is changed to give it this growling/buzzing sound?

I hope people don't think im mad, and actually understand what i'm on about.

Many thanks,

Ben.

[touring fan01]

Induction noise is the one you hear coming towards you.

[medius]

Yep, its the air flowing into the airfilter. Take a standard road car and change the airbox and filter it comes with, to a cone-type filter or airbox that allows more air in, and the induction noise is greatly increased. Supertouring cars had carbon fibre airboxes, and ducting to channel air from the front grille into the box. Here's some pics of a BTCC RML Primera I took a couple of weeks ago.





I prefer induction noise over exhaust note

[Sodemo]

Thanks for the replies on that.

Whilst we are on the subject, what differences are there between the regular S2000 petrol (non turbo) engines and the supertouring engines of old. What could you do with the older engines that you can't with the newer (slower) S2000 units?

[Bevan-L]

Originally Posted by medius

Yep, its the air flowing into the airfilter. Take a standard road car and change the airbox and filter it comes with, to a cone-type filter or airbox that allows more air in, and the induction noise is greatly increased. Supertouring cars had carbon fibre airboxes, and ducting to channel air from the front grille into the box. Here's some pics of a BTCC RML Primera I took a couple of weeks ago.





I prefer induction noise over exhaust note

Alot more to it, they also made use of slide throttle bodies etc.

Here is one without the airbox so you can see it better.