FC Zach's '87 Sport

[FerociousP]

prob pretty close to the best you'll see without more insulation of the pipe from the engine/rad air... of some sort of positive pressure ducting setup going to front of bumper.

now to get it tuned!!!!!!!!!!!!!!!!!!!!!!

[FC Zach]

Originally Posted by FerociousP

now to get it tuned!!!!!!!!!!!!!!!!!!!!!!

Yay! ! !

[FC Zach]

Originally Posted by TitaniumTT

Looks like it knocked about 10* out of the bay?

Yeah

Originally Posted by FerociousP

prob pretty close to the best you'll see without more insulation of the pipe from the engine/rad air...

Placing order now for Mazdatrix's heatshield. As soon as I pick up some good wrap I cover the header too.

Originally Posted by FerociousP

of some sort of positive pressure ducting setup going to front of bumper.

"with getting fresh air to that box, try not to overthink it." ditto
I do get positive pressure with the current setup. . . with and without the rear of the brake cooling duct plugged, obviously better when plugged however I'm optimizing the flange I made that's screwed on the brake duct to direct air better so the brake duct isn't plugged.

I am only doing that because I don't want to replace the factory duct. . Is it the best? no, but it's the route I'm taking

[infernosg]

Good to know about the weatherstripping. I have a vented hood so I'm guessing that will serve the same purpose. I didn't know Mazdatrix made an exhaust heat shield. Too bad it doesn't look like it'll work with my exhaust manifold so I'll have to make my own someday.

[TitaniumTT]

Originally Posted by FC Zach

Yeah

Kewl!

Originally Posted by FC Zach

Placing order now for Mazdatrix's heatshield. As soon as I pick up some good wrap I cover the header too.
[IMG]http://www.mazdat

I am only doing that because I don't want to replace the factory duct. . Is it the best? no, but it's the route I'm taking

Come on Zac, build that ish yourself!

Originally Posted by infernosg

Good to know about the weatherstripping. I have a vented hood so I'm guessing that will serve the same purpose. I didn't know Mazdatrix made an exhaust heat shield. Too bad it doesn't look like it'll work with my exhaust manifold so I'll have to make my own someday.

Negative... it works the opposite way. Removing the weatherstripping allows ambient air to get forced INTO the bay. Common misconception especially among the hondah crowd. At speed, the joint between the hood and the windshield is a high pressure area, removing the weatherstripping allows air to get forced into the bay. It then follows the path of least resistance and gets pulled through the tranny tunnel.

Stationary, sure, heat is going to rise so those ridiculous 2" gaps with spacers they add will relieve some of the heat from the bay because heat rises. However, as said before, at speed it's forcing air into the bay.

A vented hood on the other hand works in the opposite way. Assuming basic aeronautics are followed, the rise in the hood will create a bit of a low pressure zone and pull air from the bay. Of course this isn't the case on my car because the hood is ducted straight to the intercooler. The only purpose my drop vent hood serves is to keep the intercooler as chill as possible.

Last time I was @ LRP with the FC the ambient temps were about 104*. My charge temps of course were in the 300's, IAT's were about 120. Something something ram air something something vented hood something something expensive core.

Also of note.... my radiator fan literally broke to pieces that day... ripped it out (again literally with my bare hands and no tools) and got back on the track... coolant temps never got above 180* when it was 104* outside and tracking the car Aero can be fun!

[FC Zach]

Learn something new everyday Brian. I was sure that was a low pressure area, either way it works.

As for the heatshield. . I don't have a metal break and the fabricator I know would likely charge me ~$50 like he did for the heatshield. I also don't have that hardware that Mazdatrix uses so basically I couldn't build that for what they're charging.

[FC Zach]

Here's the latest mods. I used weatherstrip on the box and added a little scoop to the feed for the box.

[TitaniumTT]

[FC Zach]

I have to disagree somewhat with the illustration mainly in the rear bumper area. .

For example if one was to have shitty taillight seals, wouldn't exhaust pull into the car like any other vehicle. Like mine does LOL

[FC Zach]

Especially with the windows down if that makes s difference?

[infernosg]

Originally Posted by TitaniumTT

Negative... it works the opposite way. Removing the weatherstripping allows ambient air to get forced INTO the bay. Common misconception especially among the hondah crowd. At speed, the joint between the hood and the windshield is a high pressure area, removing the weatherstripping allows air to get forced into the bay. It then follows the path of least resistance and gets pulled through the tranny tunnel.

Stationary, sure, heat is going to rise so those ridiculous 2" gaps with spacers they add will relieve some of the heat from the bay because heat rises. However, as said before, at speed it's forcing air into the bay.

A vented hood on the other hand works in the opposite way. Assuming basic aeronautics are followed, the rise in the hood will create a bit of a low pressure zone and pull air from the bay. Of course this isn't the case on my car because the hood is ducted straight to the intercooler. The only purpose my drop vent hood serves is to keep the intercooler as chill as possible.

Last time I was @ LRP with the FC the ambient temps were about 104*. My charge temps of course were in the 300's, IAT's were about 120. Something something ram air something something vented hood something something expensive core.

Also of note.... my radiator fan literally broke to pieces that day... ripped it out (again literally with my bare hands and no tools) and got back on the track... coolant temps never got above 180* when it was 104* outside and tracking the car Aero can be fun!

Makes perfect sense to me (engineer). I'm familiar with cowl induction but for whatever reason I didn't put 2 & 2 together. My vented hood is arranged in a similar manner with the radiator and shroud except they're not connect at the moment. I just have the shroud exit pointed in the direction of the hole in the hood.

Originally Posted by FC Zach

I have to disagree somewhat with the illustration mainly in the rear bumper area. .

For example if one was to have shitty taillight seals, wouldn't exhaust pull into the car like any other vehicle. Like mine does LOL

Yeah, that part confuses me. I've owned a lot of hatchbacks and SUV's and the rear window/hatch always gets covered crap. Vortices coming off the sharp corner tend to curl the air back around. I don't have bad taillight seals but is it possible the fumes are only entering when the car is stationary?

[almoststockfc]

No spoiler in the illustration

[FC Zach]

That makes a difference but I'm trying to remember if Robert's 7 had a spoiler, he had bad exhaust flow in his car too.

[RETed]

Originally Posted by FC Zach

I have to disagree somewhat with the illustration mainly in the rear bumper area. .

For example if one was to have shitty taillight seals, wouldn't exhaust pull into the car like any other vehicle. Like mine does LOL

It's pulls it in from the side rather than the rear...


-Ted

[FC Zach]

I learned a couple things today, mind blown about where the high and low volume areas are contrary to where I believed they were.