tube80z

The Rouelle info was for the TC2000 touring cars not the WRC car pictured. The TC2000 YPF Ford featured a duct that reintroduced the cooling air (now heated) behind the wheel in a low pressure area. I was watching DTM this weekend on speed and it appears they have a similar arrangement. Why this increased downforce wasn't discussed. It could have been that it helped to increase front diffuser flow are allowed a higher pressure in the front of the car. Sorry, Claude has a way of saying things to get your attention but then often doesn't completely elaborate.

Get a tilt hitch. Makes a world of difference. Cary

Try this http://www.wrc.com/jsp/index.jsp?lnk=300&featureid=1020&desc=Features:%20Aerodynamics. I think this has the movies but my browser refuses to play them for some reason. And the full text article and links here: http://www.wrc.com/jsp/index.jsp?lnk=221&featureid=1418&desc=WRC%20explained:%20Aerodynamics Cary

I have it and I'd say it's worth that much. It's aimed more at the club racer and how to measure and find improvements. It's somewhat like the aerobytes series in Racecar Engineering minus the wind tunnel. But it does have some practical advice. The quality of the book is horrible though. So if you can find it cheaper I would go that route. Cary

Some more cars to check for inspiration are the Argentinian touring cars. Search for TC2000 for some pics. The YPF Ford has a very advanced radiator ducting system that Claude Roulle talked about in his seminar. It was good for 25% reduction in drag and 30% more downforce. The Ford radiator setup is also featured on the WRC.com site in a video with the cars designer. There's also a really cool discovery video that features the prodrive cars and shows them being built. And this was the season they had major issues with water splashes so they feature the ducting and what was done to fix it. Cary

A friend of mine experienced in plastic welding says they aren't too bad. The issue is the tips that are used more than anything else. He has a number of custom ones and this welder was modified to use those. As far as heat source and air mixing it seems good enough. Cary

I think you'll find in this day and age most things are measured the way they are because of convention. SAE has a standard set of definitions that are commonly used in the automotive world so people understand what each other are talking about. Cary

Canola oil works really well too. Just make sure to wash it off before it hardens. And a 5/8 bridge reamer does a really quick job of this if you have one. Cary

But the way the tested made weight much less of a factor. In a semi-steady state test the only factor would be an increase in rolling resistance. And from the results it appears that's a very minor factor. Now if the test would have been accelerating up to a certain speed then the 800 pounds of clay would have made a much larger difference. All that said I was pretty shocked with the result too. I'm still willing to bet you could have used a lot less dimples and gotten the same results. But it wouldn't have looked so cool. I wonder how many people are out there trying to figure out how to dimple their cars Cary

From what I saw in the water tank the dimples didn't seem to be any different than vortex generators on the roof line and back of the car. I'd be willing to bet you'd see a similar reduction using them in strategic places. Lexus already does this underneath their cars so at least one manufacture is on board. With regards to racing cars if it worked and was allowed by the rules it would probably be done. And usually drag is traded for downforce, which makes a much larger difference in lap times.

Yes. Years ago at the Fall endruo in Medford a guy showed up with a group B vega rally car. It had wings, 4wd, and a supercharged cosworth engine. It was the first car I ever saw that could drive over the old high curbs and shifted three times down the front straight. I only wish I had picture. Another time we had a Deacon Monza show up. A Lemans running Porsche 934 and Jose Garza's Indy car. There's been some really bizarre to really cool equipment show up over the years. BTW -- Enduro is this weekend. C

Try searching for bump steer spacers and you'll have a lot better luck.

I've found goof off works much better than brake cleaner once you've got all the big pieces off. And you can buy it by the gallon. Cary

Take my advice with a grain of salt (or a few pounds as the case may be). You haven't mentioned tires and that's the first thing I'd look at. Try and find a car that uses the same tires and see what they are using for camber gain. My gut feel is that 50% recovery from roll is too much. I'm guessing that it's going to be in the 20 to 30 percent range. If you have too much with modern radials it will give you snap oversteer. And the way you'd end up fixing it is running really stiff to keep thing from moving. With regards to motion ratios you will want to keep those very close front and rear. That will make shock tuning much easier. And I'd also make sure you're new rear suspension moves the RC in such a way that the car tends towards understeer on corner exit. If you can think about having some adjustment in the rear for RC height as that can be a powerful tuning tool. Hope that helps, Cary

Flip the pads after each weekend and you'll not really have this issue. Cary

Thread moved to a better home. Cary

See the sticky at the top of this forum for Bilstein options.

I use a similar set of pads from PFC and I'd opt for less rear torque and heat range. If you have an infrared probe check disk temps but I'd guess the rear is less than the front. In PFC I've had good results with 01 on the front and 97 on the rear. Trying 01 all around seemed to cause balance issues as the rears were in and out of the range where they worked. I know this isn' the same pad as you're looking at but the idea is the same and I can't say it worked that well for me. Cary

You can use the 280ZX pump and bracketry. A friend used this with the subaru rack and it worked just fine. Cary

550s actually. And you could feel the splitter from about 35 MPH on up. We really needed to balance it out as it would cause the front brakes to work too well at speed. It really needed an equally large wing in the back. Sorry to say we have no real data other than the feeling and how deep we could go on the brakes with it on. The car was setup so that at speed it would be level and have rake as we went onto the brakes. Under power it was slightly nose up but still seemed to help. Cary

Taking the rack apart isn't that hard to do and you could clean up the old grease that's probably gotten a little nasty. On my previous car that made a large difference to the steering feel. The old grease was more like wax. Cary

The only bit of caution I might add is that if you have tripples (or even SUs) sometimes the intake noise is greater than the exhaust. In that case an airbox will help. Cary

On some rally car prep sites they have been talking about using liquid nitrogen for removing sound deadener/undercoating. Google should give you many hints. If I had to do this again I'd seriously think about it.

By Shutter do you mean it vibrates severely? If so then I'd expect an out of balance wheel/tire or an out of round wheel/tire. Poly rack bushings and a solid steering coupler can often make these symptoms worse. Cary

They are vented, attached is a pic of the Ferrari front brakes from Malaysia this year. The rotor floats on a hat, which floats to the hub on a splined interface. Cary