[Andreas]

As the subject, are there any to buy ready made or do you have to figure out for yourself?
Any pictures would be great, saw in the classifieds section here that dyno daddy was selling the rear bumper with the venturi cut out, didn't care to much for how that looked and wondered if there are any other options.

 

[Joel]

I'd be interested to know if any of these tunnels can actually have any significant effect on a Viper at all. The underbody shape just does not suit any attempt at venturis. In my opinion it would have to start much further forward than is actually possible on a Viper. Now big wings, front splitters, canards etc, these will all have an effect. Has anyone got any figures to indicate the effect of different aerodynamic aids either separately or as a complete package.
The only tunnel that looks like it might have a chance at some success is the SVSi one moulded into the rear bumper. But I'm not sure about its appearance !

 

[FE065]

I tend to agree with Joel. Bolting something on the back when the air underneath hasn't been managed leading into the venturi tunnel isn't going to do anything. Except ruin the looks of a fine car.. A front splitter and side skirting would reduce the amount of air going under the car. Which would reduce high speed lift, and provide more vehicle weight aka downforce for traction.

 

[GTS Dean]

The GTS-R uses a rather extreme splitter and rear diffuser to control wake turbulence. I have closely observed the undertray development of IndyCars, IMSA GTP and WSC over the past 20-odd years. Since the early '90s, there really hasn't been any sort of "tunnel" under the main body of the cars at all. The rules have mandated flat bottoms, and have only allowed venturi tunnels from the area around the rear axle and rearward. What I have noted is some rather extreme sculpting of the bodywork tops and sides to control pressure gradients both through and over the top of the cars. Flat bottoms make the aero center of pressure very pitch-sensitive, but this drops off dramatically as the clearance to the pavement increases.

 

[Andreas]

I guess my question was misunderstood after reading GTS Deans post, you have to excuse my English since it is not my native tongue I have problems with most technical terms therefore I used Venturi, what I am basically looking for is a rear diffuser, over here in Sweden we often misuse the word venturi for that too.

So then my question is who makes diffusers for the viper? I saw the one that SVS carries but it don't like it to much, in this case I like the more raw that is used on the GTS-R.

 

[GTS Dean]

Well, since I started off on a tangent anyway, why not give it some gas?

http://vca2.viperclub.org/forums/sh...5&Old=allposts&Main=7633&Search=true#Post7636