Adding a spoiler to help with aerodynamics

[Punchanello]

Hello all! I am trying to figure out how to make my Civic del Sol a bit more efficient. I have a factory spoiler that I purchased a while back, and I'm getting ready to put it on my car but I'm not sure if it will increase my drag or potentially help me out.

The del Slow has a turbulent trunk lid due to the design shape. I've seen on here a few people have tried to do a Kammback mod or something similar to help them improve the airflow. I was wondering if the factory spoiler would help "straighten" the air out and send it on its way off the end of the trunk. I'm not too aerodynamic savvy so please excuse me if this is an all too ignorant question.

Thanks for any and all help,
Punchanello

[cfg83]

Punchanello -

I will let others chime in. but based on this :

Aerodynamic Streamlining Template: Part-C

I think you're Del Sol spoiler needs to "meet" the lines on this template :



CarloSW2

[vacationtime247]

That spoiler isn't going to help aero at all on the del Sol. Might look cool, but that's about it.
VT247

[Punchanello]

Thanks for the input fellas. My thought as to why it may help out was that it would (or should) fit inside the tear drop template. Granted there would be a gap and a drop between the roof and the spoiler. I was just kind of hoping that adding something to the back end of the car could help reduce the drag a little without having to cover the whole trunk.

The other thing I've looked into is extending the back of the roof out just a little bit... Sorta like taking a lip spoiler off of a hatchback and filling in some of the drop off area behind my roof. Thoughts?

[Piwoslaw]

Punchanello, look through the threads that jedi_sol started - he's doing quite well with his Del Sol.

As for the rear, try a small Kammback, just enough to point the airflow leaving the roof in the right direction. Then you can fool around with raising and/or extending the trunk lid. There is some info on this, the first two I could find are:
Flat Bonneville-type spoiler
Groar's 1997 Megane Modding Thread

[jedi_sol]

I suggest keeping and installing the spoiler....but only to use as a mounting point if you do decide to go with a kammback. Otherwise, I'm still trying to figure out possible mounting solutions without the need to drill into the trunk.

Also, in addition to driver/driving mods, proven aero mods i've done to my del sol that will not effect functionality.

1. Rear wheel skirts
2. Underbelly tray
3. Front wheel covers

4. Side mirror delete - obviously will greatly effect functionality, but the mod does give a big improvement with aero.

Kammbacks on a del sol are promising. Here are some of my previous attempts in the past:

Project: Del Sol Kammback Trial Mockup



**The dead zone between the roof and the cardboard poses an aero problem, so a kammback will definitely need a smooth transition between roof - kammback.

[aerohead]

Originally Posted by Punchanello

Thanks for the input fellas. My thought as to why it may help out was that it would (or should) fit inside the tear drop template. Granted there would be a gap and a drop between the roof and the spoiler. I was just kind of hoping that adding something to the back end of the car could help reduce the drag a little without having to cover the whole trunk.

The other thing I've looked into is extending the back of the roof out just a little bit... Sorta like taking a lip spoiler off of a hatchback and filling in some of the drop off area behind my roof. Thoughts?

Punchanello,go to GOOGLE IMAGES and do a search for the car above in the caption box.
This Lotus is a pretty good fit under the Template and scores Cd 0.29,not bad for 1967!
I would follow Collin Chapman's lead here.

[euromodder]

Originally Posted by aerohead

Punchanello,go to GOOGLE IMAGES and do a search for the car above in the caption box.
This Lotus is a pretty good fit under the Template and scores Cd 0.29,not bad for 1967!
I would follow Collin Chapman's lead here.

Following Colin Chapman's lead in car design isn't a bad thing, but are you sure about the original Europa , Phil ?

It may appear to follow the template, but it's just the side-plates.
Most of the rear deck is flat, ending in a Kamm-back.

[UFO]

Love that Lotus! It could have a Cd of .5, I'd still drool.

[COcyclist]

Originally Posted by euromodder

Following Colin Chapman's lead in car design isn't a bad thing, but are you sure about the original Europa , Phil ?

It may appear to follow the template, but it's just the side-plates.
Most of the rear deck is flat, ending in a Kamm-back.

Phil did a similar thing to the back of his CRX with good results. It is not aerodynamically perfect but the back end of the horizontal part matches the template and still let's you see out the back glass. It' like a pickup with a tonneau cover being more aero than a pickup with the back gate down.