XXO/BVGC '38 Chevy Coupe Build

[Milwaukee Midget]

Nothing like a freshly machined block, glistening in the autumn sun.

Skip the paint - CHROME IT!  Too pretty to paint.

 

[38flattie]

The Flatcad engine build kind of took a life of it's own, and progressed from what I intended. There are many aspects I dislike, and would never do again, regardless of the consequences. Vintage is vintage, and I'm mad at myself for straying.

Colin finished his 4-71 intake and blower drive system, and it's installed on Dennis's car. Now that is the perfect Flatcad engine!

[Rex Schimmer]

Buddy,
In the class you are in almost anything goes for the front end and what you have is probably more work to improve its aero than just a start over. I would think that you need to have the front of the body completely blended into the grill area and smooth back to the cowl then the axle and wheel can be a separate part with aero additions. I am attaching a pic of the front of a modified roadster, and to the guys that own this car please excuse me for not remembering your names, but you can see how they have completely covered the axle and inter wheel to improve the air flow. You could actually add some wheel covers but you need to be very careful as their shape and location can make them a pair of high speed turning vanes that could be a problem.

Rex

[Glen]

Rex, wheel covers/fairings in front or behind the tire put the vehicle into a streamliner class on a lakester, on a roadster not allowed. The axle cover is ok.

[38flattie]

Glen, I thought I checked, and wheel fairings were legal in comp coupe? I'll look it up again.

Rex, you bring up a good point about the fairings turning into wind vanes. What would you suggest? I like the idea of an axle cover, and I'm going to explore that idea.

We could make this more aerodynamic, by smoothing everything from the grill to the cowl, but we would lose some of the '38 'look'. It will cost us some aero, but I want the ability to put the fenders on from time to time, and keep that 'look'.

We'll smooth things out, while doing a balancing act to maintain the overall look it has now.

Pinkees Rod Shop, in Windsor, CO.,  has agreed to sponsor us!

Pinkees owner, Eric, will be making side panels, to cover the open area normally covered by the fenders. We planned it out this morning, so that the panels would transition from the 'fade away' area, to flush in the front. This way, I can still run fenders when I want.

Throw those ideas out here about the front tires- I'm all ears. Ideally, I would go with a straight axle, but then I would need 13" tall tires, to maintain the same stance height.

[Tman]

Eric is a good guy. Tell him Trent from Rapid City says hi.

[Glen]

Glen, I thought I checked, and wheel fairings were legal in comp coupe? I'll look it up again.

Rex, you bring up a good point about the fairings turning into wind vanes. What would you suggest? I like the idea of an axle cover, and I'm going to explore that idea.

We could make this more aerodynamic, by smoothing everything from the grill to the cowl, but we would lose some of the '38 'look'. It will cost us some aero, but I want the ability to put the fenders on from time to time, and keep that 'look'.

We'll smooth things out, while doing a balancing act to maintain the overall look it has now.

Pinkees Rod Shop, in Windsor, CO.,  has agreed to sponsor us!

I know they are legal in comp coupe, I said roadsters and lakesters.

Pinkees owner, Eric, will be making side panels, to cover the open area normally covered by the fenders. We planned it out this morning, so that the panels would transition from the 'fade away' area, to flush in the front. This way, I can still run fenders when I want.

Throw those ideas out here about the front tires- I'm all ears. Ideally, I would go with a straight axle, but then I would need 13" tall tires, to maintain the same stance height.

[Rex Schimmer]

Buddy,
I took one of your pics and butchered it up to show your car with an idea for some front wheel covers. My thinking would be to make them as a fixed fender, that would not turn with the wheel to avoid the turning vane affect. This would require that they be wide enough to allow the wheel to turn inside of them which means you would probably need to reduce your turning angle to around 5 deg either side of center. Although the frontal area of these would be several times the area of the tire/wheel, if they were designed and fabed correctly they could have a Cd that would be 5 to 10 times lower so the end result would be a pretty large reduction in drag. You would also probably need to increase the front track width to allow plenty of room between the "fenders" and the body.

Rex

[38flattie]

Sorry Glen- I'll work on my reading comprehension skills!

Hmmm, interesting Rex! I was thinking of a 'half fender', and just addressing the air behind the tire. Your design would be doable on the car- where do I find the info to build it properly??!!

Smaller tires would be a big plus-what are the smallest diameter tires available. I couldn't find any under 22", without going wide

[Rex Schimmer]

Buddy,
I like the 1/2 fender idea also as it could also be fixed to avoid the "turning vane" and it would be much easier to build and mount. I think if you look at some of the Goodyear land racing tires I think there are some 21-22 inch tires, but you are right you don't want wide. If you can get air to get past the wheel and then fill in behind with a faring  there should be a good improvement in the aero of the wheel assembly. I am a big fan of non-rotating wheel covers on both the back and the front of the wheel and if you have a good shape behind the tire you certainly can improve the aero. I have seen some CFD on the air around a rotating wheel, in this case it was a road racing wheel/tire, and it appeared that filling in the void at the bottom of the tire was the best approach.

Rex

[Glen]

The Mormon Meteor Has rear half fenders on all 4 wheels. Cleaning the air behind the tires has been known for years. Elmo Gillette and I talked about this years ago. Sharp old man.

[maguromic]

Buddy, Do yourself a favor and give Woody a call, the placement and shape is going to be very critical.  Great build and keep it up.  Tony

[Tman]

I think for all the hassle I would clean up some stock fenders aero wise and bolt them back on.

[38flattie]

Thanks Glen, I'll try and find some pics of the Mormon Meteor!

Rex, I too, really like the idea of 1/2 fenders, and think that is the route I'll pursue. I'm working on fixed inner wheel discs, that bolt on with the hub assembly. I think these things, along with a dam or cover for the axle, will be a huge improvement over what I currently have.

Tony, funny you should mention Woody. I've been talking with him about doing a computer bench flow for me, as well as checking water flow through the heads. I don't know why I didn't think of him for this, but I will be talking to him about it now!

I think for all the hassle I would clean up some stock fenders aero wise and bolt them back on.

Trent Trent, Trent- man, you just don't get it!

Anyway, My  wife an a appointment tonight, so I grabbed the car and snuck over to my buddy Thom's house.

A little pizza, a little Jack,some welding and grinding, and the hole left from cutting off the frame horns and shock mounts disappeared.

[Tman]

Notice i said clean them up I mean REALLY go to town with some surgery. Ask Eric about it, he has the skills. In my mind they would look stock from the side but real narrow and like airplane spats from the front, similar to whats beeen tossed around.