I recently refitted my bumper but left the arch liners a bit lose to let air escape like with vents. To my surprise there was quite a difference. I'll be cutting them up soon.
Another place I'm goingto try and vent is in the actual wheel arch behind the wheel (where the side repeaters are on normal cars) as looking at the flow inside the bumper there's a fair potential for venting there.
However, after stiffer springs were installed there was no longer enough downforce being created on the front end to overcome the pressure build up behind the inner fender and within the front bumper. The reason being that the springs were pushing up harder than the air was pushing down.
Keep in mind there is a HUGE difference between downforce and negating lift.
Most "hobbyists, i.e. 90% of the people" think that by adding some sort of aero mod, working or non working, is generatnig downforce.... This is 100% wrong, you are infact lucky if you can get a mod to negate lift.
Case in point is the wheel wells, by "venting them" you help negate lift generated by the highpressure in there at speed. This is not downforce!
Downforce is anything that will make your car "Heavier, than stock" by the pure act of going trough the air.
Keep in mind there is a HUGE difference between downforce and negating lift.
Most "hobbyists, i.e. 90% of the people" think that by adding some sort of aero mod, working or non working, is generatnig downforce.... This is 100% wrong, you are infact lucky if you can get a mod to negate lift.
Case in point is the wheel wells, by "venting them" you help negate lift generated by the highpressure in there at speed. This is not downforce!
Downforce is anything that will make your car "Heavier, than stock" by the pure act of going trough the air.
I am still interested in this though... so don't be so quick to judge. Controlling pressure is just as important as manipulating pressure if you ask me.
Regardless.. I have a swap 3SGTE Celica, I'm interested in more information on these front wheel well vents. I have a feeling it might be a good small step to help the floating feeling the front end gets at higher speeds.
My understanding is that is on the front side of the wheel well? If looking at drivers side front wheel, at the 9 o'clock position of the wheel well? Correct me if I'm wrong. I would think it would be on the rear end of the wheel well, but thats why I'm asking, I am obviously not a scientist lol!
any help finding information on this though? I am having a hard time finding anything under wheel well vents or vented wheel well, automotive wheel well vents, etc..etc. on the internet search engines.
Any hole that vents towards the wake of the car works fine. That is why you see many race cars use louvers to make "wakes" by having abrupt angles exposed to the air stream. These generate low pressure pockets directly behind them, and in a way "suck" the air out of the wheel wells. What really happens is that high pressure air migrates to low pressure areas.
Understanding how this works is key, since if you do, you can solve it in a lot of different ways.
I talked to the owner of a Renault R5 Turbo one time and he pointed out that the vents on the rear fenders (by the taillights) are actually scoops. Air does funny stuff.
Any hole that vents towards the wake of the car works fine. That is why you see many race cars use louvers to make "wakes" by having abrupt angles exposed to the air stream. These generate low pressure pockets directly behind them, and in a way "suck" the air out of the wheel wells. What really happens is that high pressure air migrates to low pressure areas.
Understanding how this works is key, since if you do, you can solve it in a lot of different ways.
Your saying louvers (or cut vents) towards the wake of pressure. I just want to confirm then, that means venting on the wheel well on the front side, not the rear of the wheel well exiting. Correct?
I am talking about either the top or the rear of the wheel well.
The louvres themselves most often sit on top of the fender with a clear path to the tire.
On others they have a couple of vertical louvres, in the bodywork just behind the wheel well. Some even just cut a section out, and angle the bodywork inwards, to get the air out.
I am talking about either the top or the rear of the wheel well.
The louvres themselves most often sit on top of the fender with a clear path to the tire.
On others they have a couple of vertical louvres, in the bodywork just behind the wheel well. Some even just cut a section out, and angle the bodywork inwards, to get the air out.
I think what Trance is asking, and pretty much what I want to know, is that if you do this mod to the wheel well (plastic piece), you should cut vents in it toward the front bumper of the car. So, if your looking at the drivers side front tire, pretending its a clock, you would want to cut the vents somewhere from 9-10o'clock. Is this correct, or is it towards the rear of the car, more towards 2-3o'clock. Based on what your saying (and the picture of the RX-7) it sounds like these vents should be in the rear, by the door (2-3o'clock).
Thanks TOM.. I am picturing the LeMan's cars on the site you gave me with the venting on the top of the fender. My original picture in my head though would be venting in the front of the wheel well (9 o'clock) as you spoke about being in the front of the wake. Now we are looking at the vents aft the wheel well, a la the RX7 (2-3 o'clock).
I believe this is a valuable discussion and would like to continue it.
Unfortuntely reaft vents in the body work like the RX7 is not possible for me. It would be more possible to have slit in the top of the wheel well into the engine bay, but then again that just sends the air into the bubble that is the engine bay. The only benefit is that there are louvers on the alltrac hood right above that area, it could work very well for flowing air!
I am very interested in getting the front end of my celica to want to hunker down more than is currently does. A front air dam, new reangled bottom adjustable air foil and a flat bottom piece in the front I believe would help this. Though, I would like to take in as much good information as possible.
Here is a simplified drawing of how it works.
The red is high pressure, the green is low pressure, so using "wake" slits, or louvres you generate low pressure pockets, the high pressure can migrate too, and hopefully those will be either on top of the car, or the side...under the car is a no no.
Trance4c: you are correct flat pieces, air foil and a air dam would greatly help.
Venting the wheel wells on a regular street car is like putting on a huge GT wing on it...a bit useless.... The things you already have planned should help a lot, maybe a couple of speed flaps too.
As shallow as you can (+/- 2 degrees from flat)
so deeper in the front and just a shallow lift towards the rear, this will create a bit of low pressure that will help a great deal.
As shallow as you can (+/- 2 degrees from flat)
so deeper in the front and just a shallow lift towards the rear, this will create a bit of low pressure that will help a great deal.
This is the way the car will be going, as you can see I will be altering the front bumper for a lower air foil and then a drop down piece made of flexible plastic a la C5 corvette from air dam. Then I will be creating a flat bottom panel piece to fit the shape.
so I've been looking for weeks for front fender vents and finally found something. I found days of reading about the engine bay vents....nothing about the front.
any pics of front fender pics or how and where they were placed on the Front fender?
I thought about having louvers stamped at the top of the fenders close to the cowl (3-4" forward) on the 45* surface. i would add vents /holes to the liner at the 2 o-clock(drivers) position to vent the wheel wells to the fender vents. has any one done something similar? pics?
would this be considered an aero mod? to reduce drag?
so I've been looking for weeks for front fender vents and finally found something. I found days of reading about the engine bay vents.......and i could care less.
any pics of front fender pics or how and where they were placed on the Front fender?
I thought about having louvers stamped at the top of the fenders close to the cowl (3-4" forward) on the 45* surface. i would add vents /holes to the liner at the 2 o-clock(drivers) position to vent the wheel wells to the fender vents. has any one done something similar? pics?
would this be considered an aero mod? to reduce drag?
If you follow what bill has said before on this subject you will get part of your answer. as for aero effectiveness you will need access to wind tunnel testing equipment/ a wind tunnel.
What I can tell you is:
1. Creates a low pressure area in the wheel well. (good)
2. Vents heated air out of the wheel well. (good)
how you go about doing it is up to you and what other info you can find.
A. This in turn reduces resistance (drag) that is built up in the wheel wells up front. Without proper ventilation your wheel wells are a high pressure area.
B. it also increases brake cooling efficiency. Supplement that if you want with ducting routed to provide air to cool the brakes (brake cooling ducts).
Either holes in the fender liner OR cutting out the section you wish the duct the air through the fender and applying a mesh will work, to what degree your particular idea will work I cannot tell you without actual wind tunnel data.
What bill did seems to work great for him though so I advise you try talking to him.
You could feel air flow being sucked in the holes in the front of the door where the wires go out for the power stuff in the door. So I knew that pressure was being built up in the fender, and being sucked into the lower pressure interior of the race car. So I cut the slots with an angle grinder and bent them with some flat vice grips. The flow stopped through the door.
This helps high pressure air build up, keeps well temps more towards ambient helping brake and tire temps.
i dont know why it isnt working. I tried 30 times to fix it. Google issue.
just shows the vents from the back.
On my MK1 race car I pulled the rear of the fender out so it overlapped the door front edge. You could also do what I did on the MK2
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