B-ville pipedream, what classes could an A Sedan compete in? [Archive]

Kevin Lee

10-24-2003, 03:29 PM

Here's the scenario. Suppose a "friend" has been collecting parts here and there for a salt project to be built a few years down the road. The desired vehicle was to be a flathead powered belly tank but a 28-29 sedan body is dropped in his lap. Could it be competitive at all?

What classes allow heavy modification to stock sheetmetal? Severe chops and reshaping of the body from the firewall forward. Are these classes full of people who have buckets of money to dump in a motor? Is there a class that runs relatively mild or small engines with a heavily modified body? Easier for me, uhhh...I mean him, to chop a top than build a monster engine. Will louvers make me go faster? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

My guess is it would be fun to run any car down the course no matter what the outcome, just looking for ideas to use down the road.

hammeredabone

10-24-2003, 03:36 PM

Grim, Sorry I can't answer your questions but I am willin' to send you hack saw blades!
Why not do it up like the flying purple people eater in the Robert Willams drawing?
If you did, I know a guy that would weld up two nos 40 hoods together just to see ya paint that eyeball on em'
Gordon

Unkl Ian

10-24-2003, 03:48 PM

I think in the Long Lost Classic(tm) HAMB thread on aerodynamics,it was concluded that the shape of a sedan made it uncompetitive at Bonneville.Sedans are better suited for the street,more room for a cooler in back. http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif How about selling the sedan body to help finance the belly tanker?Aside from the cost of the body,a belly tank wouldn't be any more expensive to build that a coupe of sedan.

Kevin Lee

10-24-2003, 03:48 PM

Never gave that poster a close look until now. All I have is a tiny postage stamp sized version in the back of Juxtapoz. Hmmmm...I like it.

Unkl Ian

10-24-2003, 03:51 PM

[ QUOTE ]
What classes allow heavy modification to stock sheetmetal? Severe chops and reshaping of the body from the firewall forward.

[/ QUOTE ] Something like this ? http://www.chevyasylum.com/bsf2003/wf/031018/031018_001r8.jpg Only a sedan.

Kevin Lee

10-24-2003, 04:02 PM

Don't remember the sedan part of that thread, Ian. Do you remember why they got the thumbs down? Just bored and throwing out ideas here since I'm dedicated to finishing my roadster before anything else is dealt with anyway. And that includes trying to locate a tank - that's going to take some energy. You happen to know where one is? And if I'd sell the as yet nonexistant sedan for anything it would be to finish my current project. Short story is if I get the sedan for "nothing" it stays for now. If I have to work at it at all I don't have the resources to do it right now. Pass.

Kevin Lee

10-24-2003, 04:08 PM

Ecchhhh... NO. Don't like it. It may go fast as hell but I'm too visual an animal to like that. I'm thinking the Williams poster that hammeredabone mentioned or a sedan like "that other car" that used the '40 hoods. Even a track type nose with less "track" and more "lakes".

dusty

10-24-2003, 04:38 PM

So grab a couple of sheets of aluminum and head to dustys place for an afternoon of hammerin and e wheelin.!! Build that tank. How did the cherry picker work for ya. We just got in yesterday from a couple of weeks of r&r.

Kevin Lee

10-24-2003, 04:58 PM

Glad to know someone is getting rest. The cherry picker worked famously. Suppose I should give that back now huh? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif I've got the motor out again for the final welding on the frame and mounts. Got all of my pedals to fit in there too...under the floor. Baby steps but getting closer.

dusty

10-24-2003, 05:28 PM

Will be ready soon to pull the body and motor and get some paint on the frame and body interior. Still have a few patch panels to do so no immediate need. I will come down and get it if its in your way as I know the space limitations you are working under however, you are more than welcome to keep it to use until I am needing it. I am working up here in Gladstone these days remodeling a house. You know the backround on the work situation. Any way, I am not in your area these days. Hope to see ya tomorrow.

Kevin Lee

10-24-2003, 05:49 PM

It's not in my way at all. It's back in the Parts Cave along with the body. Motors are shoved to the back wall along with the rolling parts and I actually have room to walk around the frame as I work. I'm sure I'll be done by the time you need it. In the meantime let me know if you need anything. See you tomorrow.

dusty

10-24-2003, 05:59 PM

I did notice the way you skirted around that tanker thing I suggested!! hehe

Unkl Ian

10-24-2003, 10:25 PM

My apologies to the Chrisman Brothers.

Phil1934

10-25-2003, 03:54 PM

I believe Worm was selling fiberglass tankers. They were building one up last time he posted regularly. HEY WORM!

av8

10-25-2003, 07:39 PM

U was thinking along the same lines, Unk. Kent Fuller has been edumacating me with regard to hot-rod aerodynamics, and he maintains that some of the less-likely iterations actully work better than the classic favorites. For example, he feels a roadster pickup is a better shape than a simple roadster. A roadster has a low-pressure area aft of the cockpit and this is an area that's received a great deal of attention from the seriously fast competitors, with solutions ranging from lover farms to break up the boundry layer, to parking the 'chute packs their to spoil things.

A tonneaued roadster pickup has a positive-pressure area aft of the cockpit, and by playing with the angle of the tailgate it just might be possible that it can become an effective Kamm-back tail.

Now, compare the profile of the back of the Model A sedan body with the profile of a C5 Corvette or a Ford GT-40 . . . Hmmmm, isn't that interesting.

I think the idea has real merit. And nice illustration, BTW.

Unkl Ian

10-25-2003, 08:58 PM

Don't remember where I found this.The text is hard to read,but what is important is the pictures.Figure a looks like a Model A"The rectangular cylinder(Figure 7.15a) has rampant seperation at all sharp corners,and very high drag."The coefficient of drag is 2.0 "Rounding it's nose(figure7.15b)reduces drag by 45% but the coeffieient of drag is still high."Coefficient of drag is now 1.1 "Streamlining it's rear to a sharp trailing edge (figure 7.15c)reduces drag by another 85% to a practical minimum for a given thickness."coefficient of drag is now 0.15 "As a dramatic contrast,the circular cylinder(figure 7.15d) has one eighth the thickness and one threehundredth the cross section,yet has the same drag." This illustrates the importantce of streamlining exposed axles and steering. I was just reading on the land speed mailing list,a tear drop has a coefficient of drag of .05 when moving with the rounded end forward.Turned around backwards the coefficient of drag increases to .4

Deuce Rails

10-25-2003, 09:14 PM

You'll want to run in the Competition Coupe and Sedan category if you want to make the modifications you mentioned.

If your flathead is running without a blower on pump gas, your class would be XF/GCC. The record for that class is 156.701 mph, owned by Webster Racing, set in 98.

I think you can beat it.

E-mail or PM me if you want any more info.

--Matt

Unkl Ian

10-25-2003, 09:19 PM

Is there a maximum amount of chop for those classes?

Unkl Ian

10-25-2003, 09:43 PM

Freebie airflow simulator. (http://www.grc.nasa.gov/WWW/K-12/FoilSim/index.html) Land Speed mailing list archives (http://www.team.net/archive/land-speed)

Phil1934

10-26-2003, 05:21 AM

That picture is testing the Navy did. The bowling ball with less drag has sand glued to it, which explains the rough skin on a shark. However that's in water not air. aAwater droplet rounded in front and tapered in the rear is an ideal shape. Also what a Kammback car is, Kamm found out the taper in the back can be removed without much increase in drag. Also I doubt the Cd of 2 as a sheet of plywood is 1. Therefore a reduction in frontal area is good no matter the increase in Cd.

Deuce Rails

10-26-2003, 07:57 PM

[ QUOTE ]
Is there a maximum amount of chop for those classes?

[/ QUOTE ]

Yup. For Competition Coupe and Sedan, the minimum windshield height is 5". The front and rear chop must be equal.

Interestingly, the class rules demand a chopped top, a full belly pan, and lengthening of the body from the cowl forward by 12". Also, the engine must be set back a minimum of 25% of the wheelbase, but not more than 50% of the wheelbase. The rules do seem to encourage cars looking like the one Unkl Ian posted.

If you can't meet these requirements, then you need to run in the classic category, which allows all cars from 1928 to 1981, IF you have all stock panels. It's a lot easier to do well in this class with a 49-50 Ford or Mercury, and even easier with a later Camero. A Model A wouldn't be too competitive here.

Grimlok, you may also want to look at the Vintage Sean classes. You can do a 3" chop, but not other major modifications.

(Thanks, Unkl, for the fun airflow simulator link.)

Unkl Ian

10-26-2003, 09:30 PM

Gene Winfield.I think I would tuck the headers inside the bodywork.Since the are shaped like a big tear drop,any chance an Isetta would be legal?

Kevin Lee

10-27-2003, 03:40 PM

Just wanted to bump this since the Sedan could be falling into place. All real effort is still being placed on the roadster so whatever happens happens - but if the sedan materializes I think I may go for the competition coupe/sedan class. Unblown on gas sounds like the most realistic. If nothing else I get to chop and heavily modify a sedan body later next year.

Deuce Rails, you will have an e-mail.

Tman

10-27-2003, 08:00 PM

Duece Rails, For competition Coupe, you only need ONE of these items.Top chop, belly pan, nose lenghtened, 25% engine setback.

Deuce Rails

10-27-2003, 09:02 PM

[ QUOTE ]
Duece Rails, For competition Coupe, you only need ONE of these items.Top chop, belly pan, nose lenghtened, 25% engine setback.

[/ QUOTE ]

Shit, Tman, you're right.

I completely missed the introductory part where you only need ONE of those rules. I'm sorry if I passed along bad info.

--Matt