What will a Gas Coupe that's .30 Cd stock be in race trim?

[PatMc]

Oil streaking would be excellent on Harley Davidsons and Dodges.  Will it work on vehicles that aren't "total loss oiling"?

[FoundSoul]

If you have a location near your home that is known for being windy and winds are generally from the same direction, like an on shore wind on a scenic over look or something similar you can do basic tuft testing by parking the vehicle facing into the wind and taking video or lots of still picture of the car as the wind blows. It also allows you to sit the car at a slight angle to the wind to see what the airflow does with a slight cross wind.

Larry

That's a good idea.... I bet I could use my shop actually for this-- I've got a pair of 4' tall 5hp 30,000cfm fans in the back wall behind the dyno.  They blow out normally, but I can probably use the motor controller to reverse it and have my own simpleton wind tunnel that would work for tufting at least.

[Dynoroom]

Oil streaking would be excellent on Harley Davidsons and Dodges.  Will it work on vehicles that aren't "total loss oiling"?

Come on Pat, all ya gotta do is drive behind the Harley and the process works........    

[jacksoni]

What lead me to start thinking on this was last week out on the salt I met a gentlemen running the same chassis in Gas Coupe who stated that the Cd was 'significantly lower than stock in GC race trim', and it got me wondering just how significant. 

It's only a few mph difference per 100th of Cd, but that's a few mph...  just trying to get my estimates as accurate as possible, and to gain a better understanding of all of this...

Been crewing for customers out there for years, just helped Lee Sicilio's team record with an exit speed of 283mph last week and every year come back more excited than the last.  Can't wait to get my own car out there and drive instead of just crew/help others.

Pretty sure I am the guy here as I remember the converstation. I based my statement on a couple of things. A stock Firebird is reported to have about a .34 Cd. Gary Eaker (owner of Aerodyne and A2 wind tunnels) ran in the late '80s with a tunnel demonstrated .23 Cd. The car I built before the 240sx was as close to his as I could get it. We talked with him about it as well as studied the published information. A lot of things can be done, of course. Keith Turks earlier vintage Camaro that was mentioned in this thread and was the subject of a HRM article I think was reported at about Cd .24 (IIRC, can't lay my hands on the article at this minute) Also, Don McMeekins runs a similar beautifully prepared car (240SX, car #280) and has had it a tunnel as well. Again my memory is he told me Cd in the .24 range. I apologize if I am misquoting him. As the 240sx is about 2ft lower frontal area and Cd at least as good as the 'Bird if not better, I think the proposed speeds are possible. I have been struggling with my engine and have only gone about 160 with the 240sx where went 170 with the same engine in the Firebird. Good Luck.

[FoundSoul]

Thanks for joining in the discussion Jack!  Sorry I didn't get back by with the 'geek, we got busy and the time we did roll past when we could have stopped you didn't appear to be in the pit so we rolled on. 

I appreciate all the feedback and I hope this thread will help others with the same questions as well.  I'm happy with an estimated .25 Cd number right now that I'll use for my math, if I can improve on that further then it's gravy. 

I'll be visiting A2 as well and will have more concrete numbers then of course.  I'm hoping to pull that off prior to SW2013 but we'll see how the year/budget goes. 

If we can help you at all with your project please let me know-- making engines run well is what we do!   

[jacksoni]

No problem- we made I think 17 passes chasing stuff ( a fuel pressure regulator that was not locked down so dropping pressure every run, and then a miss at high speeds that was a coil (or two). Have spent a lot of time, effort and of course $ trying to get the engine to run the same as 08 and 09, with little luck. Exact same configuration, fuel/ignition map etc the only slight difference being location of air intake on the front, which of course could be a factor. But problem has been in two different cars as well. I have a line on the problem and will see when that is investigated further. Will try to get the car ready for spring at Wilmington but likely will not be at 2013 with it (big vacation trip right before and effort toward Udo's Bonneville Bugeye which we ran in 2010. He has a nice little D motor to go into it.) Appreciate the offer. Put up some stuff in a build diary. Would like to see what you do.
    Oh, and the guys at A2 are great. We learned a lot with our time there.