lart951

does having the sunroof removed increases drag at high speeds?

dime1622

yeah, itll bump up your coefficient of drag a little bit - but our cars are pretty aerodynamic (Cd of 0.33 whereas the '86 911 was 0.39), probably would bump it up close to that of the 911. regardless, ive had the top off and made 140 without any noticeable difference in the butt dyno. flipping the flap at the front up at about a 45 degree angle should cut down on some of the air entering the cabin.

Redlyne_mr2

Turn up that little wind defletor.

lart951

I was just saying because yesterday

special tool

Luis - I know why you had problems. I have run across that guy - its Fireball Freddy in his '74 Foxbody """Cobra"""

lart951

Okay that's the car. I didn't know it was a 74, but hell was fast.

Btw Jim, I don't know how to tell you this but I am still a little unhappy about the work you did in my car. Yes I know you told me that you were going to reduce the groos weight. But don't you think you went too far? come on I need the engine & doors a least dude.
The wheels are you sure that's the right offset?

Daddio

Drag goes up exponentially with speed, so at 140 mph you have 8 times as much aerodynamic draga as at 70 mph, or 2X speed = 8X drag. So, whatever increase in drag you were getting by virtue of removing the sunroof, it was 8 X as much at 140 as at legal highway speed.

OTOH, lift also increases exponentially with speed, so whatever lift is normally generated by the curved roof by Bernulli principal, would normally be 8X as much at 140 as at 70 mph.

Removing the sunroof would spoil the airflow and therefore much of the lift over the top of the car, but would still help alot in vacuuming all the crud outta your car. Wearing goggles may be worthwhile in this situation.

lart951

The above run was done by profesionals in a controlled enviroment

testarossa_td

Yeah, that's the ticket....yeah....
The shot in your avatar....did you or somebody else shoot that?
And how?

azmi951

I got 100 on a section of track without it off then 105 with it on in the up position. It was a long straight.

Mercedesben

I am surprised that at 140 the hatch did not blow out!

lart951

Is a picture from the box cover of a 1:24 model, I used corel photo paint to changed.