Reduce under the hood temps?
 

Saw this post:

http://www.ft86club.com/forums/showthread.php?t=50460

Valid?

Are you trying to reduce intake temps or underhood temps? IMO his testing is flawed, the intake temp is mostly based on the air it's picking up and will go down with moving. If underhood temps, mount temp probes around the engine bay and do some repeatable testing.

I'm assuming the op's intake manifold is getting heat soaked in the thread link you posted.

You could probably achieve the same with a hood with vents. Of course that would be more expensive and won't stop rain from entering.

If you are chasing lower under hood temperatures Robispec says
in reference to this:

is your car overheating? Is heat soak effecting your supercharger?

if the answer to both is no....then WHO CARES.....sure in theory its better, but 10c (20F) drop isn't that big of a deal......

The stock cooling system in my FRS works really well, no issues even in 105F days at Thunderhill.....even with the AC on in the hotpit.....car ran perfect...

I will be trying a different thermostat soon

Completely invalid. He's raising his temps. Remember hood cowls on muscle cars? They're there cuz they suck in air. Removing the gap behind the hood does the same thing, reducing airflow through the radiator. It only helps when you're parked.

Get a vented hood if you need to lower temps. We can help you with that. We're also testing a CSG radiator :)

What's the deal with venting a hood then having water, dirt, bird poop flowing down the vents when parked in the rain? Is that the trade off for venting the hood?

It's not ideal on a DD.

Since a vented hood isn't ideal for DD, I'm curious if anyone perhaps has a separate track only hood? Kind of like how many people have a separate set of track wheels & tires and track only brakes that they put on for track days. Obviously a vented hood isn't going to fit in the trunk of the car along with your spare wheels and equipment, but you could always switch out the hoods at home before leaving for the track event. That way you get you extra the cooling and downforce at the track where you need it, and the rest of the time you stick with your stock hood for DD where you get the protection from the elements.

I would think that swapping out hoods should take no longer than swapping out a set of wheels. I have a buddy who only puts on his rear spoiler for track days, which is probably no more than a dozen days out of the year.

Sure we all love our cars and look for any excuse to go canyon carving, but in our normal DD I would think that a non-vented hood would still be ok for most of us. I'm not FI and I live in beautiful Santa Barbara CA where it's never too hot or cold. So I don't know, maybe a vented hood is a necessity if you're FI and in Texas or Arizona. Here in Santa Barbara though, the weather is nice but we got a lot of trees. So there are a lot of leaves and crap flying around in the air that get stuck in the wiper area of the car. I definitely don't want that stuff getting into the engine bay. There are enough smells coming from there as it is.

Most authentic hoods have trays to catch things that go into the vent... although I haven't seen any authentic vented hoods for the FRS/BRZ myself yet.

Either way, it hasn't been a big deal in my experience.

I must admit to being a little in lust with Robipec's vented hood

@omegared19 has Prova vents installed an cut out the inside. Dropped engine bay temps significantly he said.

Hello Mike,
Yes, it does help temp drop temps when park and sit in the pit lane.
Can you tell me how to test the "reducing airflow through the radiator."?
I would like to test it.

Thank you

Ace

Ace,

Tape string/yarn at the back of the hood where it is raised, and you'll see that the air is going into the engine bay, instead of exiting out. This happens because there is a high pressure zone where the hood meets the windshield, and the net effect is that LESS air is being conducted through the radiator.

You can log engine and oil temps through the OBD2 port

-Mike

Okay, I will take video of testing at next practice at Dec/14/2014.

Also I am looking for ""How to data log?" Do you have kit to sell?

Ace

Cheapest way is to use a Bluetooth OBDII module with an android app "Torque".

We use a Aim solo DL in our cars.

You still have plenty of vents underneath the car, so the flow through the radiator may not necessarily be reduced, but in order to increase the flow through the radiator you would need vents on the hood and they should be closer to the bumper than to the windshield.
http://hanchagroup.files.wordpress.c...11/frs_001.png
(the red areas/lines show low pressure regions.)

This should work:
http://www.carbon-fiber-hoods.com/co...by_Seibon.html

If you want a more permanent gauge than your phone (to see your temperatures) you could install this: http://www.ultra-gauge.com/ultragauge/

(I have done opposite on my daily driver, I installed a grill block to reduce my fuel consumption and accelerate engine heating in the winter and use it to watch my temperatures and even though I blocked almost the entire grill I can barely get the cooling fan to turn on in a traffic jam.)

How effective would cutting out the fender trim pieces so they vented air?

I've read people saying they can feel a lot of hot air escaping, but what about at speed?

I'm planning on trying this before going for a vented hood.

I actually wanted to post this in this thread.
http://www.ft86club.com/forums/showp...23&postcount=2

If you added a lip just before the panel underneath the engine you would provoke low pressure region behind that lip, which would suck air out of the engine compartment (if you removed the panel).

(Just as this spoiler/lip on the trunk provoke as low pressure region behind it:
http://images.machinedesign.com/imag...0000049861.jpg )

This wouldn't be aerodynamically efficient but as long as you don't care about top speed or fuel economy it wouldn't matter.

I would love to see someone try out some options with the fender vents being functional as well...I think Prova's fender vents are actually wire mesh, but you still need to cut out and enlarge the open area behind them...

I'm also curious with fender vent cut out. if anyone has photos of where they cut out, that'll be super helpful!

I'm confused... you claim the IAT's dropped 10* on your other thread, how do you know that if you're not logging them??

I use OBDII reader on my iphone.