Modifed Sports

[SPARKY]

My neighbor is thinking about modifying his '68 Opal GT to run in Modified Sports:

1. How much may one chop the top--there is no mention of windshield height that I can find other than in Comp Coupe section.

2. Driver seating position?  May the drivers cage be put in the center similar to a Funny Car with a roof  escape exit ?

[jackson]

Those sound like D. Warner questions.  If I was him, I don't know how I would answer.  On the positive side, I think Bill Ward ran a whole lot faster than I think I would in one of those short little Opels.  I don't know how he kept the horse in front of the cart in that one.  There may be something to that body style that we don't know.

[836dstr]

At one time I had planned on building an Opal GT (had one sitting in the side yard with a bad engine). I thought the aerodynamics would be pretty good. You see some Opal GT front ends grafted on other LSR cars. I was a little concerned about the short wheelbase also. I had talked to Bill Ward and found out he ran the stock wheelbase.

I looked at the Rule Book during my first El Mirage meet trying to figure out what body class I could run in. I found out that Modified Sport was the only place it fit. I misinterpeted what the rules said about modification in front of the cowl. I read it as requiring the stock wheel base. I thought that getting a fiberglass frontend (still available) and extending the wheel base a couple of feet would make for a nice Race Car. I went so far as to get a Catalog for 'glass front ends, can't remember the name of the Company.

Subsequently (after giving up on the project and selling the car) I saw several Sports Cars running as "Roadsters" @ El Mirage with long wheel bases. Went back and reread the Rule Book and saw that modifications in front of the cowl was allowed. I think this would make a good Race Car.

Tom

[JackD]

We built an Oatmeal GT with a 1200 cc Kawasaki turbo motor in it and trimmed it to look like a Mini Corvette.
It runs Autocross and really scoots without much noise.

[836dstr]

The Opal GT has a pretty laid back windshield and rear window. With the way the window frames on the doors fair into the top it might be tough to do a chop job that would look good, and probably wouldn't gain that much of an Aero advantage. Wouldn't it be cool to have the modeling ability and access to a wind tunnel to check this stuff out before hacking and welding.

A question, did your friend plan on entering and exiting the car thru the escape hatch in the roof? The GT isn't really that tall, and if the top is chopped, getting in and out of the car with a full cage and side bars would become difficult. Then there's issue of getting the driver strapped in at the starting line. Probably not a big deal, but just trying to think ahead.

With a properly built cage I'm wondering how the escape hatch would work.

There was another stock bodied Opal GT at Bonneville this year that I believe ran in a smaller engine class. I don't know how they did, but it was a great looking car. Bill Ward was running a "C" motor in his car. Maybe someone can put you in touch with them. Nothing like starting out a little way up the learning curve.

GOOD LUCK and keep us posted on the car build!

Tom

[SPARKY]

It already has a sun roof, so the hatch is a natrual---after pondering what you and others wrote ---I looked at the car again---maybe we need to look into riding semi side saddle---so that it would be possible to see forward easier--sit diagonally across the car, enter from the pass side make a left hand steer and a pass side brake and throttle  

[836dstr]

Sparky,

As you probably know already, ergonomics and drive "comfort" are big issues in going fast. I'm trying to envision what you mean by sitting side saddle in the car, but I guess you mean having the drivers butt in the seat on the right but the clutch/throttle/brake on the left which would not be a problem if reversed. The rule book states that the driver must sit in the stock position, so butt on the left and pedals on the right would work. It's a narrow car so the offset would be minimal.

Being a 6'2" driver in a '27 Street Roadster was a challenge for me. Two different roll cage configurations and 3 or 4 changes to shifter/switches/chute release positioning finally got me to the position where I can be suited up and strapped in for an hour or so and still be comfortable. The big difference for me was to get the shoulder bar or main hood wide enough and all the controls within a 6" circle of my right hane.

The guys I mentioned being at Bonneville this year were Black Opal Racing #6666  E/FMS out of B.C. Canada. Maybe you can get a contact # thru BNI, same with Bill Ward.

Keep the driver physically comfortable in the car, and you will have a happy driver!

Tom

P.S. If you extent the front end and move the engine forward, you could also move the firewall forward and allow the driver to sit in a natural position straigh ahead.Maybe I should have built the Opal GT afterall, I'll always wonder what might have been.

TG

 

[Richard Thomason]

Don't even think about putting the driver in a truely weird position. He/she needs all the help they can get at speed. An educated and experienced posterior is key. Don't put the body and/or head sideways to the direction of travel. The inner ear can be fooled but only for so long. There is a lot more involved in driving at speed with no references than one realizes. I have seen people get off the track, and have to stop and essentially get out of the car to figure out where they were.

[Glen]

Richard is right, it's in the catagory of rear steer, don't even try that. The
tech committee would reject either of those two.
 Glen