enlighten me a bit please. can you speculate or see if air is prevented from pressing down on the G's cover? are there exit points for air or water?

 

i wonder what kind of material besides ABS and CF would be desireable for this project. someone said something about lexan, which would def be cheaper, but would that really be shapeable enough? or is perfectly flat what is best? i have some lexan in the garage i think, maybe ill take a look at this later

 

i have another brand of lexan that i planned to use. polycarbonate is the material. lexan is the company. mine is in a roll, so kinda flexible. i plan to use it flat. i believe you can heat and bend it. you don't really want any flex in it while driving.

 

I plan to get some abs sheets together this summer, and fab up a front undertray they can mount up to the front of my Stillen lip. I'll extend it to about where the oil filter is so that stuff can be easy accessed. Now the rear, I looked at the rear today while doing some exhaust work. I can't really tell if the spare tire well hangs lower than the fender at any point. If it does thats a problem because I want to use a flat sheet (obviously) to span the fenders and attach at the rear bumper. Ill have to make a cut out for my ricer (EVO2 style) muffler now though. in any case I believe it is doable. With gas prices its worth a try. I plan to epoxy and layer the sheets for strenght and just use L brackets to attach them to the car.

 

I know this thread is a million years old but I haven't forgotten about it and it's still on my to-do list. A month or so ago, I actually did buy the material I plan to use. I walked up and down every aisle of Lowe's and Home Depot. I finally settled on some white flexible sheeting that is marketed as waterproof wall paneling. I have jacked up the car and scoped. I am just concerned with blocking heat dissipation. I also think that a Stillen front lip does 80% of what we are trying to do anyway, right? Since it directs the air down lower and also around the car. So I am still unsure as to where to place the paneling. I do know I need one in the back because I have an Ionic one-piece and I'm sure I am getting a parachute affect right now.

 

Are you talking about an Ionic Roof spoiler? I have one on as well. IMO we would do better to focus on proper placement for hood vents. I read all those article on autospeed and it seems hood venting may offer more benefits than the underpanel with less work.

Also



Lots of posts, but whichever pics where on here have been deleted.

 

The stillen lip does direct the air lower, but turbulance is still created behind the leading edge of the lip. My solution is to attach the unpaneling level with the bottom of the lip and extend it to the back of the bumper like a "real" splitter if not to the where the stock splash guards end. Ill attempt the rear panel/diffuser first as I think it will be easier to complete. I've scaled down my previous idea to just a square sheet the width of the spare tire well running the lenght from the just behind the rear beam to the rear bumper.
I plan to mount it level or with a slight rake under the spare tire wheel and make a seprate piece to cover the angle from the back of the well to the bumper. Ill start mocking the thing up with cardboard soon hopefully.

 

Got some cardboard out today.

 

that looks like it would creat MORE drag, not less....unless the flat surface continues forward of the axle. Otherwise it's just an underbody parachute...

 

Its just cardboard and not the final design by far... The leading edge will be turned up so it wont catch air above it and wider. Also, the panel will be higher than the bottom of the gas tank so thats even less of a problem for turbulent air. There is no way a panel could continue infront of the axle being a solid axle car and all. Anyway unless the underbody a diffuser is OEM, and even then they dont go infront of the rear axle.

 

you could have it be two piece with the panels running more or less into each other when the car is sitting normal, but split from the rear axle so it doesnt interfere with the movement.

 

No, how would a roof spoiler create a parachute affect? I'm talking about an Ionic one-piece rear ground effect.

You totally lost me. Why are you comparing hood vents to aerodynamic paneling? One is for heat dissipation (probably at the expense of aerodynamics) and one is for ....well.... aerodynamics (the topic of this thread).

P.S. Here is a link to my one-piece Ionic rear and my hood scoop.

 

Good job Pulsar!

 

http://www.infinitihelp.com/diy/gsed...ment_video.htm

You can see the G35 panel there.


http://g35driver.com/forums/showthre...t=air+diffuser
Other diffuser pics

 

what about blocking the front grille openings? at least during the winter?

air slamming into the engine bay instead of flowing over the car causes a lot of turbulence. granted during the summer the rad needs that cooling. but i would want to somehow prevent it from flowing down to under the car and hitting the panels we make.

seems pointless to smooth out the bottom if i have a huge lower opening slamming air on top of it.

 

this site seems to cover everything?

http://ecomodder.com/forum/showthrea...utions-47.html

grille blocking
http://ecomodder.com/forum/showthrea...-block-60.html

1974 C&D article
http://www.ecomodder.com/blog/2008/0...ves-mpg-by-25/

goldmine, aero forum
http://ecomodder.com/forum/aerodynamics.html

 

so i went under the front bumper today to investigate. i can definately attach the shield to the subframe. i planned to stop just shy of the oil drain plug. BUT i found the tranny plug is halfway to where i wanted to stop. then right behind it is an air scoop going behind the tranny.

i wanted to make it so i wouldnt have to ever remove it, but i could if necessary. so i don't really mind covering the tranny plug, but i doubt it's a good idea to block this "scoop"

plus i don't want my polycarbonate to melt touching the exhaust

edit
my sheet is 80"x30" i need ~70" across the front, so 30" stops just in front of the woven section of exhaust leaving clearance for the scoop. i'll have 10"x30" excess which is perfect to block my lower grille. cutouts for the wheels leaves me with 2- 7"x17" pieces. i can place them beside the foglights.

i guess i should just get those screw tabs Nissan loves to use. then i can easily attach it to my FG bumper cover (so i have to dril) and subframe pre-existing holes.

 

if i ever get mesh to cover my lower grille opening, i want to attach lexan behind it. i would also like to somehow attach a horizontal, maybe diagonal piece above to direct air coming in the main grill upwards only. i would only be blocking off 1/3 at the most of my radiator.

i just have no idea how to attach behind my lower grille while still looking ok. i guess i can use some sort of glue. being clear it should look ok, but being without any mesh for 2 years, it cant look worse.

the horizontal piece i have no clue at all. maybe i'll use black coroplast and just gorilla-tape it to the main bumper? then it can rest on the radiator at an angle. maybe i can tape it to the center beam of the rad...

any thoughts???

should i use zip ties, glue or L brackets and screws for the poly behind the lower grille?

 

I don't plan to run this one on the car, its my first "real" model. Feeling out spacing and angles more than anything else. I'll try to get some pics of it mocked up in place tommorrow.

 

i'm guessing that's for the rear?

 

Yeah, Im just focusing on the rear at the moment.

 

Sorry, you said Ionic and the first thing the I thought of was my roof spoiler, I don't think they make anything else for the 6th gen. One track mind I guess.

I am brought up hood vents in relationship to aerodynmics because of this article, http://autospeed.com/cms/A_2162/article.html and I also thought we were talking about better gas mileage, cooler engine = better mileage? I know my engine gets pretty hot and often thought about some sort of venting or scoop or something to help cool it down.

That's a lot of work you did on your Maxima, looking good.

 

One thing that has prevented me from doing my underbody panel for 2 years is where does the air go that cools the radiator?

Part 1 Testing Pressures
AutoSpeed Part1

air enters the grille opening to cool radiator


but if we seal off under the engine, where can the air go?


stock it leaves underneath


if we seal underneath, we should allow some venting, and ideally vent the front of the hood



but i am no way going to cut into my hood!

Part 2 Making an undertray
AutoSpeed Part2

Part 3 Helping air escape
AutoSpeed Part3


So no one has overheating problems sealing everything off? I understand this article is saying that once air enters to cool the radiator, without an exit, pressure is so high, no more air will enter.

To me we should have a vent somewhere located, probably towards the front, maybe behind an AIR DAM, for engine air to escape???

i think i read someone has air come out into their wheel wells since it is already turbulent? so cut into the fenders' interior???

 

well looking at my oem undertray that no longer fits, my new one would only go 7" further back.

but helping the air escape the engine quicker should still help cool the radiator, especially if you block some of your grille. some guys sealed their rads to suck the air in and vent it out into the wheel well. this eliminates all the pressure and drag in the engine bay.

 

i fit my grille block front pieces. covered behind the main grille and the bottom sides. diverted air from below into the radiator. now less air will get underneath. and more air will flow over.

now i just have to measure, cut and attach my under body polycarbonate piece back to the oil drain. that will keep air from coming up into the engine area, reducing more drag.

 

Very nice, looks good too. My ABS should be here next wednesday to my underpanel. The stuff was cheap too $37 or a 8'x4' 1/8" sheet. I may do one for the entire car now.lol

 

ABS will be a lot sturdier, but my 8'x4' of coroplast that i used for this cost me $15.

but i'm using polycarbonate for my underbody. i think it ran me $60 shipped for 2- 30"x80" sheets. was 2 years ago so i forget. but i see it more readily available on eBay now and cheaper.