Vertical or What Roof Rails

[Cajun Kid]

I hope I can structure this question so some of you can picture what I am "trying" to ask.

I know the roof rails have to be parallel. I was told to use 90 degree angle,,,  But since the roof of my Studebaker is not flat... is the vertical part of the roof rail supposed to be 90 degrees vertical to the roof or the ground ?

Am I over thinking this ??

Charles

[Glen]

They should follow the contour front to rear and at 90 degrees. The whole purpose is to spoil the air from causing lift. Yes they work.

[Cajun Kid]

I got the "follow the contour"  but 90 degrees to what,,, the roof sheetmetal ? or the ground ?

Maybe my eyes are crooked ?

Charles

[Stainless1]

Either one would probably spoil lift if you get sideways.

[Bville701]

Does this help?

[Cajun Kid]

Bville,, yes that helps,,, the Stude just has more contour, both front to back and side to side ( crown )

I will do my best...

Oh by the way,,, Nice Job on mounting your  ISP Stealth Head and Shoulder Restraint System,,, looks very good, strong and safe.

Charles

[Bville701]

LOL  Charles, that's not my car. I just looked it up on google to see if I could help you out, but yes that person in the picture did a great job.   

[Cajun Kid]

Well I thought since you lived so close to Disney Land,,, you would have more than just the old  E ticket for a ride. LOL

Whomever car that is they did a good job on the Head Restraint,,  they added more bracing from the shoulder to the cage side diagonal bar.  nice touch..  Not that I am an expert,, but ISP is 45 minutes from me and I am very familiar with there stuff and the mounting.

Charles

[dw230]

If I may, I think you were told to use the 90 deg. material because of the ease of use.

The 'parallel' mentioned in the rulebook is the measurement side to side, front and rear they must be equal. They rails must also be equal in the cross measurement, right front to left rear and left front to right rear.

Mount as close as possible to the outside edge in order to get the maximum benefit if needed.

DW

[Cajun Kid]

DW,, thanks for the input,,

I have .080 flat aluminum  1.5 " wide,, was going to brake a 90 degree bend in it to get the max 3/4" rail height.

By moving the rails out.. then I have multiple contours to contend with,, the Studebaker roof is far from flat,,, I will have a front to back contout (no problem,, it does not change the angle),, but the side to side and rolling crown contour  chnages the degree... so to keep the vertical rail "straight up"  90 degrees to the ground/sky.. then the angle is more than 90 degrees to the flat bottom mounting surface ??

Charles

[Bville701]

LOL Charles, I use to work at Disneyland (go figure). But the modified roadster we run is the best E ticket ride I've ever been on.   

[stratman59]

Charles,

We had to bend our angle more than 90 degrees to a 90 degree angle on the installed roof rail. I think the closer you get to 90 deg. installed angle the better they will work if needed.
Just my stinking thinking.

Robbie

[jdincau]

     Since the purpose of the rail is to trip the airflow when the car gets sidewise having it 90 degrees to the local contour produces the most airflow disturbance.
      On the other hand having it 90 degrees from horizontal will produce the least airflow disturbance when traveling in a straight line.
      You have to decide whether the theoretical reduction in drag is worth the expense of making a rail with a continuously varying angle.
Just another guy with an opinion.

[Peter Jack]

Charles:

You're in the right part of the country. Go look at a cup or nationwide car and follow their lead. You could probably even find someone who could tell you why they do it the way they do.

Pete

[McRat]

It's not going to cause much drag.

Use this:  www.mcmaster.com type in: 8982K562 , it's $5 for 8 feet, and McMaster is known to be very expensive.

It will readily conform to the roof in both directions.  Put it on like a drip rail on a VW bug, and it will even help in the rain.