Hey guys,
I will start working on Spike's aero, And we know that fooking industry doesnt make shiat for our car.
Anyways I found someone that makes universal rear difusers in the states.
They go for 299.00 I will be ordering one in a couple of days.
The only thing is that the shipping is 145.00 to toronto I have talked to they are willing to work out the shipping if I can get more people.
They are made of fiber glass.




And here is how they woul look roughly.







-Manuel

will my car get turned into a supra roughly too =] Sorry manny Couldn't resist.


I take it 1gs don't have the curves to pull off a difusser.

Of course you can put a diffuser on a 1g. However, you shouldn't just add a diffuser, you need to balance the aero with a correct amount of front downforce by a splitter. Otherwise you'll just understeer more.

I plan on running aero on my car next summer and 1g's have a good rear rake which is nice for a diffuser.

Yes what tashko said.
Here is what I'am planing, rouhgly.

This stuff has become my newest interest, soo much to know when it comes to aero and how such small things can make such a difference. Balance is very important and an underbelly can make a world of difference in the handling of a car. Manual, remember i told you i had fallen in love with lotus Elises and must own one? Look up pictures of the underside of one of those. Theres is way too much going on under a DSM to achieve that. Get a front splitter, rear diffuser and fab up a belly pan and call it done is what i would do.

I got a couple aero books this christmas and look forward to reading them in the next month or 2.

Anyone have a wind tunnel i can borrow?

There's a big wind tunnel just out side your door. String, tape, and two friends with a video camera in another car. Easy to see low and high pressure points...

aren't m3s the same too smooth under belly?

Once my car is running I think under side might get something done. Although if parts break all the time its another thing in the way =]

Well, since there is no interest on this, can we move this to the handling section?

hmmmm, i've been dealing with a company in ajax that does cnc sheet metal bending for work. Wonder if they'd be interested in laser cutting some sheet metal for me? Maybe its arts and craft time with a couple sheets of bristol board, scissors and masking tape...lol. The guy that i'm dealing with there seems quite nice and like most fab shops their quite slow these days. Heck, machine shops phone me all the time asking me if i have work for them. Manual, before you get your hopes up, i'm not doing this till my car is up and running hopefully in february.

Anyone ever built an engine diaper? A lot of organizations require them, esecially in drag racing.

Lol Manuel. Yeah, probably should get moved since we've hi-jacked your thread. Maybe the discussion will peak some more interest in a GB.

I've slowly started to make <some> progress on my 'aero to-do list' but what I have to get done before April is:

- 1ga composite hood (just started sanding the plug for the mould tonight)
- 1g composite bumper/air dam
- 1g composite splitter (have the cardboard template ready)
- 1ga diffuser
- 1g side skirts

The 1g bumper splits the air stream in two locations and only the bottom location, which doesn't provide much real estate, will provide any downforce on a splitter. My feeling is that a 1g splitter will only require a mild diffuser to balance it out.

The other thing I started wondering about how the pitch and roll will affect the function of the side skirts. Once you start letting high pressure air under the car in the middle of high speed turn at maximum compression, are you going to experience a noticable loss of aero grip? Same with accel/decel, the pitch change on the splitter will generate more front grip under braking which will mess up the brake balance at the same time the rear diffuser loses some effect. Under acceleration squat, a flat bottom will trap air under the car and tend to 'lift' it. If you don't put enough rake in your suspension set-up it would be noticable at high speeds depending on your spring rates & power.

Anyway, some things to think about in your sleep.

I'm also waiting on rules for 2009 to be issued for Autoslalom, SoloSprint, SCCA Solo, and CSCS since I have to make sure all my aero mods meet all the requirements.

I'm pretty sure all of this 'aero' stuff will be pretty useless until your speeds exceed 100mph. Probably faster...

Actually, aero stuff starts producing around the 80-100km/hr mark. Items such as air dams and spoilers are effective at lower speeds since they help aerodynamic efficiency rather than generate downforce.

As with anything to do with cars, it's a trade off. Aero will need more power so that the increased cornering speed you gain isn't lost to reduced top end on the straights.

That would work great for stopping my oil leaks too!

My plan pretty much is to concentrate on the front bumper. As in ducting for the rad, intercooler, oil cooler and a pair of brake ducts. The goal is is to seal everything up and force the air to go to all these places and not be wasted. I'm not near ready to start worrying too much about the aero benefits but I will try to make a splitter and a belly pan for the engine compartment.

Tashko, what do you think of the hood vent placed directly over the exhaust manifold? Good idea? I really don't want to cut a hole in my carbon hood.

You are so lucky, I am reading about it right now.
I will getting one of this pretty soon, I have been looking fordward to installing one this for a while now.

http://www.dsmtuners.com/forums/app...7-road-race-engineering-hood-vent-2.html

-Manuel

P.S, Do you have my bolts?

Air management is important. I'll have a sample of a part by the end of Jan. which I think you will have left off of your list. I'll let you know when it comes in and you can check it out...it's a simple part.

I would wait on making any holes in the hood until after you have done a splitter. I like clean hoods.

The splitter (I assume will extend to the front axle line) will create low pressure under the car. The hot air in the engine bay will be drawn down under the car along with air coming in from the sides (hence the reason for side skirts).

I think, ideally, your inlet will be drawing in fresh air from outside and not the engine bay. The engine bay airflow will be in through the rad, around the engine, and out down below the car at the trailing edge of your splitter.

As long as you can supply enough air to the inlet that it doesn't need to draw on the engine bay air you shouldn't need to cut holes in your hood on a street/track car.

Hopefully you won't be seeing high IAT after doing your air management, splitter, and protecting your air inlet from the rest of the bay.

The location of a hood cut-out should be based on where the low-pressure zone is. Generally, cars have a low pressure zone about 1/4 - 1/3 of the way up the hood which is caused by the air being pushed over from the front. This is were the string and tape comes in handy. You could find out exactly where to put extraction vents for the most benefit.

//edit

Just saw Manuel's post...I should start reading DSMtuners every now and then...I had to laugh at the guy that put a SPAL plastic fan in front of his exhaust and melted it. Gee, did he not wonder why the OEM fan on one side is metal and the other plastic?

Tashko the part i missed from my list is my air inlet to my air filter. I will probably be making a modified headlight that will allow airflow directly to the filter and eventually a box to enclose the air filter from the engine bay.

I'll probably end up getting the hood vent and placing it about 1/3 the way up the hood/over the exhaust manifold. Will have to do some testing to see where the low pressure zone is. found the low pressure zone on my golf the other day when i was too lazy to clean the large amount of snow off the hood of my car. You'd see the snow blow off in the high pressure zones quite quickly and in the lower pressure zones the snow would remain on the hood. As i accelerated to different speeds it would cause more snow to blow away but the low pressure zone towards the front of the hood stayed put till i reached speeds like 120km but some still remained even after being on the highway for 20min and reaching my destination. It was actually quite interesting to watch even as i made lane changes you pressure zones changed to cause snow to blow off.

The last thing is I really don't like how there not centered over alot of the guys hoods on dsmtuners because of the hump. The cars got to look good too

You will lose aerodyanmics Mike

Defeats the purpose of your diffuser

Has anybody with a hood vent reported problems with windshield fogging? I'd be curious if the hotter air from the vent does anything when it's blown accross the windshield.

EVOs come with them stock? sure there undercarriage isn't sealed but either will mine even with a splitter.

^^
We drive talons, not EVOS, big difference

Hmmm, I wonder if this diffuser business is even worth it to make a real noticable difference in a DSM. I mean if I had one on my car, I highly doubt I will even be able to say, "oh yea, feel that diffuser working ?" lol

Other than it looking nice, without some professional real world wind tunnel testing and placement, I think its useless. I mean the Supra looks like it can use it as those turds go at pretty high speeds and are tail happy, but on a DSM, for some odd reason I don't think you'll be able to say: "Yup you can certainly feel that diffuser!"

Regarding the vented hood and windows foggin up, I think that is less of an issue than people driving their cars around with the heater cores and ducts removed

Definatley a great idea, but without REAL testing, I think its useless.

Well I guess I should go out and buy wind tunel, last time I checked Suaber were selling theirs.

Wrking on aero is not useless, Its like saying that adjusting your suspensions in certain way, wont give you better 1/4 mile times.


Everyday and I mean everyday, There is companys racing diferent types of cars from miatas to F1.
While the F1 teams and other high end leagues do use a wind tunel.

small teams like the ones in the SCCA cant afford a wind tunel and they still use difusers, skirts, splitters and anything that can help the car handle better. How? well they use common sense.

Look at this guys,
http://www.scca.org/hub.aspx?hub=4

You think the can afford a wind tunel? Probably not.

-Manuel

I would definitely be in for a bolt-on type ducting system for the 2G's to direct flow to the Rad/FMIC.

I just modified the stock ducting and supplemented it with some aluminum sheet metal and foam pipe insulators. It's sealed up pretty tight. You can find some photos here: http://www.putfile.com/album/194117

On a track like MoSport, or a track where you can get up to a reasonably high speed, the aero (if you can make it light enough and tough enough so that it doesn't come off) could give you an extra few kph through a turn, which can make all the difference in the world if things are close. But if you do it wrong, it could hurt you as much as help...

Heh. I still remember the first day I took my 1G to 235kph. Passing through 190kph and the rear started feeling a little squirrelly. Then at 210 or so it just PLANTED it. That's when I thought, "So THAT'S what the rear lip spoiler does..."

Tashko you think i could get some pics of your template...im also looking to put something together in terms of a front splitter for my 1g

Hey Elias,
All you need is carboard and a marker to make your own.

It is very simple all you have to do is make sure to mark where will you want your mouting points.

-Manuel

im sure ill tackle it once the weather is a bit warmer... i just wanted some pictures for refference it seems hes got a bit more of an in depth perspective on aero than i do ... unlike most dsm builders my goal isnt auto cross or 1/4 mile runs ... id like to achieve a top speed of 180 mph with my dsm and have it somewhat stable...anyone else have any experience with building such a dsm ? id like to see this thread stay alive in terms of advancement of aero for our vehicles

I am working on it, I cant do anything at the moment because is pretty danmed cold.
But this will give you an idea of how is should look when its done an over with.
But that is just the splitter, undertray and side skirt will complement it.




-Manuel

now thats what im looking to make or have made...the issue im having is preventing the splitter from flexing .. at the same time id like it to be as light as possible thats where things are getting tricky in my case..Manuel id like to see more pictures of your actual pieces as you progress it would be nice to see ...

It will not be for a while, But I will post pics and info on how is going.

-Manuel

Yo MAny.

Did you find a place where we could buy the Plastic Material???

If yes, how much???

Ghislain.

yO ghix,
I did find the plece but if I tell YA, Ill have to kill YA.
















































































































55bucks, 4x8' 3.5mm thick. I think I might need something thicker which they have too, thats only what I quoted.

-Manuel

What plastic are you looking for?

http://www.johnstonplastics.com/

Yeah, you gave me that info before thats the people I called.

The guy in the picture above made his of a material called something that I can remember.Not kevlar or carbon.

And he races this car,enjoy the vid
http://blip.tv/file/1607922

a question for anyone with an answer ...but a splitter that covers a large portion under the engine bay what does this do for temperatures in the engine bay area when heats attempting to escape ?

That is the main reason that I will be using a hood vent.
Plus I will not be using the splitter on daily driving, so i wont have to worry about sitting at the light an such.
I also will make it a bolt on insted of ribbeting or screwing.

-Manuel

what about venting on the bottom of the splitter towards the rear ? or would that disturb air passing under to much and take away from its effectivness ?

Yeah I think that would disturb the air, See I wanted to put NACA ducts for my brakes ducts atach to the underneat of the tray, but I dont think that would be smart.

-Manuel

why on the tray and not on the bumper ? you could feed tubing to direct airflow to the brakes ?