Anyone have any experience with this:

http://www.aprperformance.com/index....d=70&Itemid=44

I'd be curious to know actual benefits at track speeds. Obviously we can bench test thing to death thinking about what it COULD do but, I am curious to hear abou some real life experiences.

As a bonus, for those of you running dual duty, like myself, any noticeable MPG gains with this?

Thanks
Adam
CLT Racing

 

until you find someone who has a wind tunnel.. you might as well be bench testing.

 

https://www.evolutionm.net/forums/sh...=rear+diffuser

Fireball did some testing with the rear diffuser and gained some top speed on the straights.

 

was it the same day? weather conditions? denser air? was there a tail wind? did he get better? etc.

 

I just installed mine today and just from the looks, you will probably be able to get a few extra mph on straights, especially the one at Road America where Fireball did his tests. I can guess that because the air will not be able to get trapped behind the rear bumper. Also, you will get some additional downforce which may hurt your straigth speeds. So I really have no idea what I am talking about.

 

You know as much as I know, from reading that thread. It's going to be hard to find someone who has performed a thorough objective test, that is why I tend to take personal reviews with a pinch of salt.

 

good questions. w/o concrete data with some sort of baseline in very similar conditions, it's impossible to know the utility of this piece.

 

Downforce doesnt always equal drag. Drag always limits top speed however.

 

Yeah I guess it is hard to simply determine the actual benefits of this piece. I guess I'll take the dive and post up any noticeable or detremental effects.

I did speak with APR and of course they say it is a noticeable difference at track speeds with regards to the amount of downforce it helps to create but, nothing on any sort of MPG gains for daily use Evolutions.

 

just bought one, I added holes in the bumper behind the plate (take the plate off for racing) so I don't get a parachute, hoping for 10-15mph in the "kink" at CMP.

 

Can't help you on the track benefits. I bought it to keep the snow from packing in under the bumper. It's proven to be pretty durable. I like to bash my car around in deep snow. After getting my 06 f-350 4x stuck for twenty minutes, I had to prove the evo wouldn't have got stuck in the same place. It didn't, but I knocked a side skirt off. Did improve my milage by over 1 mpg when you drive very easy(read that as no boost) on the hwy. Same exact trip/conditions 60 mph.

 

Sounds like your ready for a rally in the snow Well thats good that you gained 1 mpg. Anything is a plus in an Evolution

 

True, but also, the lower the car, and the flatter underneath the car=faster speed due to the fact that the air will be moving faster underneath the car, cause as you stated, the air doesnt get "distracted" if you will and find all those little crevises, therefore it's a straight shot, means less drag. I dont think the additional downforce hurts the speeds on the straight, in face it should increase it, since your cutting it thinner. That's my take on it......

 

Why would you want to ADD weight to your car? You've got Corey and Anthony to worry about in STU next year. :LOL:

 

I hear ya!!! I also compete in NASA's TTs heavily as well and was curious to see what the benefits are at track speeds.

You aren't too shabby yourself