Exhaust Flow and Aero

[Slide]

^^^ same question as above. I am thinking about the flat bottom, diffuser design and its relationship to the exhaust muffler and exit. I am currently going to cut the rear bumper higher (so it doesnt act like a parachute) and the diffuser can extend a little longer. However I need to decide if I want the exhaust to run all the way to the back, and if so, exit out the center or tuck up and maybe come out the sides of the rear bumper...

[SPARKY]

what kind of car?

[Slide]

2013 Subaru Sti Hatchback. We are trying for 206 mph in the mile (airstrip attack/mojave mile etc)

[gkabbt]

^^^ same question as above. I am thinking about the flat bottom, diffuser design and its relationship to the exhaust muffler and exit. I am currently going to cut the rear bumper higher (so it doesnt act like a parachute) and the diffuser can extend a little longer. However I need to decide if I want the exhaust to run all the way to the back, and if so, exit out the center or tuck up and maybe come out the sides of the rear bumper...

Here's a Yahoo link for Mike Reichen's Mitsubishi EVO.

https://search.yahoo.com/search;_ylt=A0LEV1pBH0VWiwUAH_tXNyoA;_ylc=X1MDMjc2NjY3OQRfcgMyBGZyA3lzZXRfaWVfc3ljX29yYWNsZQRncHJpZANKNkRqZExDbVRmNnh1WVFqWk1CLmZBBG5fcnNsdAMwBG5fc3VnZwMxBG9yaWdpbgNzZWFyY2gueWFob28uY29tBHBvcwMwBHBxc3RyAwRwcXN0cmwDBHFzdHJsAzIzBHF1ZXJ5A21pa2UgcmVpY2hlbiBtaXRzdWJpc2hpBHRfc3RtcAMxNDQ3MzcwNjI1?p=mike+reichen+mitsubishi&fr2=sb-top-search&fr=yset_ie_syc_oracle&type=orcl_hpset&fp=1

He went 237 at Maxton and IIRC has been in the 215 at Wilmington and over 200 at Loring.
His car should give you some ideas for front end aero. Also, IIRC his exhaust does exit out the back.

HTH,
Gregg

[Slide]

You are awesome! Thank you!!!

[SPARKY]

I would put the exhaust straight back under the car  aimed back down the track--

I know a blown classic altered that picked up 5+ MPH by changing the exhaust from blowing out to blow back---also you will not have to put a steering correction to offset the side thrust of the single exhaust!

[manta22]

If a post is a "cut & paste" it would help to cite your sources.

Paragraphs, paragraphs, paragraphs!

Regards, Neil  Tucson, AZ

[Slide]

Hey greg, was checking out those links. Apparently the exhaust on that Evo exits the front bumper... man that thing is quick (for us 4 cylinder awd guys that is!)

[gkabbt]

Hey greg, was checking out those links. Apparently the exhaust on that Evo exits the front bumper... man that thing is quick (for us 4 cylinder awd guys that is!)

Those are old pictures when he did have the exhaust out the right side.

Here is a pic of from Loring in July:



In this pic you can just barely see vapor coming out the exhaust at the back:



I'll see if I have any better pics.

Gregg

EDITED TO ADD:
Here is my Google+ link to the above pics:
https://plus.google.com/photos/115248360774022016668/albums/6175608284824009201

[gkabbt]

Not really that good of a pic but you can barely see the exhaust. It is below the battery charging leads and is next to the second strake.



HTH,
Gregg

[Slide]

Yep! I see it now.'looks like he has it just sticking through the diffuser.