Jump to content
HybridZ

Understanding Race Car Aerodynamics


Recommended Posts

Here's my not very popular take on intercoolers and radiators. They should be sealed together so that any air that goes through the IC has to go through the rad. Having the IC sit 6" in front of the radiator means that the air really isn't forced to flow through it, and since the fins are a restriction to airflow they don't work in that position as well as they would if the air had to go through. The air just goes around for the most part.

 

Ideally you would have an air box from the front of the car to the radiator opening, IC sealed to the radiator, radiator sealed to the core support. This would mean that all the air that comes in the front of the car has to go through the IC, radiator, or both.

Link to comment
Share on other sites

  • Replies 42
  • Created
  • Last Reply

Top Posters In This Topic

It was all gonna be sealed up like that anyways. But by eliminating the intake from the hood I don't know where else I could effciently put it unless I do the V-mount idea. I don't think it should be too hard to duct and seal the V-mount if I have sufficient enough at cutting and welding which I'm learning to do now in school

Link to comment
Share on other sites

Here's my not very popular take on intercoolers and radiators. They should be sealed together so that any air that goes through the IC has to go through the rad. Having the IC sit 6" in front of the radiator means that the air really isn't forced to flow through it, and since the fins are a restriction to airflow they don't work in that position as well as they would if the air had to go through. The air just goes around for the most part.

 

Ideally you would have an air box from the front of the car to the radiator opening, IC sealed to the radiator, radiator sealed to the core support. This would mean that all the air that comes in the front of the car has to go through the IC, radiator, or both.

 

Popular or not, this gets a +1 in my book. for street cars, AC Condensor at the same time (ideally, find a combination of the three that lets you run the AC condensor and the IC side-by-die in front of the radiator core)

Link to comment
Share on other sites

It was all gonna be sealed up like that anyways. But by eliminating the intake from the hood I don't know where else I could effciently put it unless I do the V-mount idea. I don't think it should be too hard to duct and seal the V-mount if I have sufficient enough at cutting and welding which I'm learning to do now in school

Plenty of examples to look at. If you put the intake into or next to your radiator duct, that's good. You can see pics of preith's beautiful car here: http://forums.hybridz.org/showthread.php?t=121944&page=2

 

You could also put it in the cowl like EMWHYROHEN: http://forums.hybridz.org/showthread.php?t=138065&page=9

Link to comment
Share on other sites

The subject of laminar to turbulent transition is exquisitely complex. Please don't believe that a few general principles are enough to give accurate estimates of boundary layer physics. That said, cars are incredibly "dirty" aerodynamically, and the extent of laminar flow for a S30 Z is negligibly small.

 

I would seriously doubt that one could perform enough aerodynamic enhancements to obtain measurable mileage improvement while driving a "legal" speeds.

 

I think for this thread we need to stay on track. He's not talking the fundamentals and intricacies of fluid dynamics to describe reductions in drag and improvements in downforce. And as you get closer to the skin of the car at any point you will always have laminar flow, just depends on how small of a thickness your looking at. We need to keep it fairly simple and for the most part he's on the right track IMO, so let's look at the general areas of HP and LP and how to route the air to make it work. We will leave the hair splitting to another thread.

 

Sealing the IC, TC, and Rad are all good ideas and well worth the effort. Foam works fairly well sandwiched imbetween them in small strips.

Link to comment
Share on other sites

Memory foam, I have alot of it. Works great, starts at 3 inches and you can compress it down to about a half inch. I cut it on my band saw about a 1/2 inch wide and glued it on the tanks and just stuck it in the core of my pete between the A/C and the Rad. Been there for several years now.

Link to comment
Share on other sites

The foam sounds like a good idea, but sorry to get off this line of thought but I got a couple more drawings. Still not the technical ones but I lost the printer cartridges to my printer and can print out the pics I wanna trace for them so I'm tracing pics I already have printed out. I changed the hood and added a wing. Who thinks the wing looks to ricer-ish? I'll be doing another one today but putting my 3-peice spoiler on it to see if it looks better. The side veiw one is why I'm tracing and not doing freehand, I'm not happy with my free hand drawings.

Picture 001_thumb.jpg

Picture 002_thumb.jpg

Link to comment
Share on other sites

Ricer to me means that you put something on that doesn't do anything, or you put something on for looks. If wings work and are used, then they aren't ricey. If they're bolted to the trunk of a Honda where the force of the wing will literally tear out the bolts or the car is a street driver that never sees the kind of speeds that would justify adding the wing, then that's ricey. That's my take anyway.

Link to comment
Share on other sites

Well, I want it as a street driver and take to the track every now and again. I want additions to be functional and appealing. Maybe I could have the wing and only put it on when at the track, every other time just have something in the mounting holes to prevent nature to seep through inside the car.

Link to comment
Share on other sites

I think wings look good on a z. Mean as hell looking. Take a look at Mike Kellys car. Wing and front air dam and vgs. My take on ricey is similar to Jon's, if your car cant move out of its own way and you have all of the crap on it and it is loud as hell, its rice. If it gets a move on, with all of the crap on it, is race. One letter seperates it all, and the z can definitely move out of its own way.

 

jimbo

Link to comment
Share on other sites

You were talking before about reducing drag, a wing like you have illustrated will increase drag whereas the common bobtail rear spoiler will give very little drag but a significant increase in downforce.

 

On the question of stability and the S30, with a decent front spoiler, an undertray and one of those bobtail rear spoilers you have the basis for a very stable car. The prime cause of instability with the S30 is air getting under the front of them and lifting the front up.

Link to comment
Share on other sites

You were talking before about reducing drag, a wing like you have illustrated will increase drag whereas the common bobtail rear spoiler will give very little drag but a significant increase in downforce.quote]

 

 

The wing actually had the least amount of drag per the wind tunnel data. See test #10,11,12 for whale tail, short and tall spoilers vs test #21 for wing.

 

http://forums.hybridz.org/showthread.php?t=121877

 

Aero is a package deal, we all can agree on that. The wing can make more downforce at the expence of drag. See the data and it confirms.

 

jimbo

Link to comment
Share on other sites

I think perhaps another comparison thats worthwhile is between tests #17 and #21. #17 is with upper half of air damn blocked off on a car with MSA III and no ZGs, test #21 is with MSA III upper half blocked off, APR wing on low setting, ZGs.

 

Test #17 drag: 89.7hp

Test #21 drag: 88.2hp

 

Adding a wing does not necessarily mean more drag.

 

Dave

Link to comment
Share on other sites

The wing does look very nice on the Z. Looking at all those photos of the build up your cars make me wish I could still be in Arkansas right now working on mine...I don't get to go back to work on it til the last week of March :( But I'm saving up as much money as I can to get it running again when I do go back.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...