RussB

David Vizard's books have helped me in the past (check his name on Amazon). His "Tuning BL's A Series Engine" book is the bible for Mini tuners. More recently he's worked with SOHC Fords and small block Chevys. He tests everything with a flow bench and/or dyno. He's been quoted: "I don't have opinions. I have a dyno."

I wonder if any Audi tuners have used Vizard's cam matching program?<ul><li><a href="http://www.davidvizard.com/camshaft.html">http://www.davidvizard.com/camshaft.html</a</li></ul>

ryoung

Unless the software has (or allows you to enter) the detailed specs on the intake manifold, exhaust manifold, head port dimensions, etc -- IMHO, trying to optimize a cam profile by itself is imposssible.

I have used "Engine Analzer Pro" from <A HREF="http://www.performancetrends.com/">Performance Trends</a> with much success on a racing motor, but you'll need a lot of data on your motor to use it without guessing.

RussB

Vizard mentions that to specify a cam, port volume and length is helpful but not essential. Here's his input data form: http://www.davidvizard.com/FORM.html

Before discounting this, do a Google search on both the web and newsgroups on his name. He knows whereof he speaks.

PT's site looks interesting.

Here are Vizard's notes regarding data that's needed by his program to select a cam:<ul><li><a href="http://www.davidvizard.com/Notes.html">http://www.davidvizard.com/Notes.html</a</li></ul>

ryoung

they were very good, and he does know what he's talking about.

Still ... even if the <A HREF="http://www.davidvizard.com/FORM.html">Form</a> is accuratey completed, it looks like he totally ignores the tuning effects of the intake manifold and exhaust runners/collector and the flow capabilities of these, the muffler, and the mass-air flow meter.

What are you trying to accomplish? Is this for street or track? Have you had your head on a flow bench? IMHO, Vizard will get you in the ballpark; but if you want to extract maximum HP from your motor, get the Performance Trends product. Beside probably doing a better job on the cam, you'll also easily be able to identify the weak links in the motor for your next upgrade.

RussB

My '84 5000 will never be a rocketship, so I just concentrate on making it reliable, comfy, economical, and pleasant to drive. It's slow, and that's fine with me.

I have other (non Audi) vehicles that are closer to toys that I use when I feel the need for speed: a Westfield Eleven car (1100 pounds, 1380 cc, Cosworth pistons, overlength Carillo rods, flowed Bryan Slark big valve head, Weber 45DCOE carb, Kent 286 cam, high lift alum roller rockers, lightened, toughened, and balanced everything that turns, header, big sump, straight cut gears, limited slip, etc.); close to stock Ducati 916 bike; Honda CBX bike with sport bars and pegs, Morris mags, PM brakes, triangulated aluminum swingarm, Ohlins shocks, etc.

While assembling the Westfield's motor about ten years ago, the engine builder (Tom Straubinger) and I bought miscellaneous parts from the company (APT, in Calif) that Vizard owned at that time, and bounced cam selection ideas off him via telephone. (I gather that he's since moved to Charlotte, reflecting I suppose his growing interest in making Detroit iron go fast.) His A-Series book helped enormously during the engine build.

I just learned of Vizard's cam selection program and was curious if any Audi speed freaks had used it. I see lots of messages here regarding boost tricks, but very few messages regarding cam selection.

Has anyone documented their flow bench results of modifying Audi heads, or dyno results of various cams?

ryoung

About 5 years ago I bought a head from Vizard @ APT for the Ford 2L OHC motor in our Formula Continental.
... And the Westfield must have been a blast!

<img src="http://www.pccchicago.com/images/paul/midohio/MidOhio_wallpaper2.jpg">

RussB

Do you still have it? Did you build its motor yourself? What cam did you use? Has it run since then without catastrophe?

I found Bryan Slark near Salsbury, UK, while I was over there. His heads were at the time winning in Mini saloon racing, so I bought one with slightly smaller valves than his all out model.

I still have the Westfield. It's fun to drive IF THE ROADS ARE EMPTY so I limit to early morning weekends and occasional autocross.

Was the head on yours done by Vizard, or just resold? Did he provide flow numbers? How has it worked for you? Are you the car's driver?

Russ Bellew