Ludo's Corsa A Question

[Rob77]

Hello all!

Just wondered if anyone could shed light on something that has been confusing me and a few mates...

The link below is to a video of Ludo's Corsa A doing two runs up a 1/4mile stretch.

What is it that make the weird noise when he changes gear? (Sounds like a horse neighing!!!)

There is a seperate dump valve noise (the traditional TSSSHHH), which can be heard when is doing the burnout at the start, but then the "horsey" noise too!

Someone I know mentioned compressor surge, where the pressurised air is forced back through the turbo, making the rally car chatter sound, but I thought this damaged turbos, and by the looks of the spec on the guys car, he wouldnt seem the sort of person to do something to damage the turbo!

Anyone got any ideas?

Rob.

www.corsacrew.de/runslurcy2.mpeg (http://www.corsacrew.de/runslurcy2.mpeg)

(If that doesnt work go to: http://www.corsacrew.de/Downloads.htm - The video is called "Ludo 11,8 sec bei /4 mile" and is at the bottom of the page)

[Jack]

Its the dv/wastegate. Watch the boost gauge, it goes tsshh at lower boost and chirp at higher revs. Mine does it. The ch-ch-ch is, as you say, pressure coming back into the turbo and hitting the fan blades which isn't good for the turbo.

Also looks like he has a boost limiter on 1st and 2nd.

[Rob77]

I think he runs an HKS SQV d/v, whether that explains anything or not I don't know!

[Philsutton]

thats exactly how mine sounds, mines is just on the standard waste gate.

[Novasport]

Thats fookin evil!!! but I like it, woo ha ha ha

[Rob77]

thats exactly how mine sounds, mines is just on the standard waste gate.

What dv do you run phil?

[Philsutton]

i dont run a dv well only the standard one that it came out the factory with. I dont get any of normal dv sound like you could hear when he was doing a burnout, mine just does what his was doing when going down the 1/4 mile all the time.