I take your suggestion and remove the front rotary symbol. Here is how I close the sides and bottom gaps:

 

hey sammy where did you get that foam from?

 

they are made by home depot materials: angle aluminum bar and heavy duty weather seal.

 

Sammy

Nice work.

Looking at this pic, you have made a nice bracket to securely attach the undertay to the radiator. I thought about affixing a brace from there but wondered how much pressure (at high speed) it might exert on the radiator fixings. Do you feel this is not an issue? Also do you feel it would be a problem to completely close the gaps between the radiator and undertray forcing “all” the air up through the radiator (ie some needs to pass under to extract heat)?

Look forward to hearing the results.

 

Nice job---you dont want to completely inclose it--at high speed the air would build up in front and cause problems.
Again --nice job.
olddragger

 

Oh i forgot to mention--once you remove the rotor symbol you will have to add a very thing/small support for the middle of the air dam. I used just a very thin threaded rod, painted it flat black and you cant even see it.
OD

 

actually there are 2 brackets there and the undertray is not attached to the radiator at all. one L-bracket is attached to the radiator to close the gap and the other bracket is attached to the undertray for better support so the tray won't be forced down too much by air flow.

 

totally agree. that's why the undertray has a few slots for air to exit and you want to keep them open.

 

Sammy,

I just ordered a radiator from BHR and want to take the same kind of on-track data at Buttonwillow on the 12th of July.

2 questions:

1...what scan tool is that...can I just plug it into the ODBII port...does it need external sensors?

2...how did you mount your cameras...do you have a DIY thread on that?

 

i am using the blitz r-vit ds engine data system and it just plug into the obdII port and output the data into the headunit via rca connetors. you don't need external sensor for water temp.

i have 2 bullet cameras mounted inside the car: 1 under the center mirror with a wide angle lens, the 2nd one is mounted on the roll cage. the 3rd camera is mounted on the rear bumper next to the license plate light.

all 3 camera signals are then input together with the blitz unit into a pip (picture in picture) processor, and then output to a portable dvr.

 

That's awesome...I would love to see it all in person...I live in Reseda 1/2 the time and Newport Beach 1/2 the time.

 

Sammy - Good job on the ducting. Ducting made a lot of difference on track on my FD when I had a more compromised cooling system using a FMIC with a Koyo rad. I noticed as much as a 5*C drop in coolant temps. That should be everyone's first step. Some of the more hardcore FD track guys drop a light in the engine compartment and look at the rad from the front of the car. If you see light peaking around seal off any gaps.


The problem with unducted FMICs in general on the RX7 and RX8 is that they slow down the air flow through the rad and also divert it up and around. Any heat exchanger that doesn't have air going through it will have its capabilities suffer.

With my custom Vmount on my FD running 10 PSI of boost at Buttonwillow in 90+*F ambient temps, my coolant temps never got above 96*C. In stop/go rush hour traffic, my coolant temps rarely go beyond 90*C which is where the low speed fan engages.

Before anyone contemplates going through this expense, you should do the free and easy stuff - duct and seal off all the openings around the rad and try to get direct air flow to the rad. You should also get the REmedy water pump or some kind of underdrive pulley so your coolant doesn't cavitate.

 

*scribed

a lot of good info here

 

anyone had any thoughts about mounting a third pusher fan in front of the intercooler (or the aircon condenser for that matter) .....

 

Pushers are WAY less effective than pullers.
Pullers can already become a restriction at speed.

 

Went to the same track this Monday and got the following data:

In the morning session:
Ambient temp 86F
Peak water temp 219F
Peak oil temp 240F
Runing duration 18 mins

In the afternoon session:
Ambient temp 96F
Peak water temp 222F
Peak oil temp 244F
Running duration 15 mins

Changes made:
Sealed the bottom & side gaps between the radiator & and shrould
Added a bracket on the underbody tray
Remove the front rotary symbol
10% coolant, 90 distilled water, 1 bottle of water wetter
Cut oil cooler vents on the splash shields open more

Conclusion: Water temp drops ~10F compared to the last track day

 

Not bad, not bad at all. And I assume you did push her to the high rpms? 8-9K?
That is also basically what i am seeing and if i want to cool her down, she does pretty quickly. My fans usually do not even come on when i pit after a cool down lap. I bet yours didnt either. Good job.
Yall keep your ears open for another cooling option that may be released in a week or two. Still in beta testing. From someone you are not familar with.
olddragger

 

i shifted mostly between 8-8.5k.

as a comparison, skyse3p's peak water temp was over 230F on the same morning section but he shifted mostly at 9k!

 

those high rpms are a killer.
Its time to release another little secret of mine.
pull and separate the a/c condenser just a little further away from the radiator The a/c at idle will not be as good butt......
Might help some, might not.???
I only have 2 more "stupid secrets" left.
olddragger

 

Which interrupts the airflow through the radiator at speed.

 

Nope
OD

 

Uh, yeah. Already did the due diligence on that.
If you want to separate the AC condenser from the rad, you have to put at least 6" - 8" between them before the net pressure after the fans is equal.
There just isn't enough room to do that correctly.

 

I grant you , that you have a lot more working experience with heat issues than i and you probably have tried everything you can think of, but remember when others didnt believe your oem hood cooling mod? They quoted good theory and well known principal? Wasnt true was it? A slight separation--probably less than a inch-- will not cause any great benefit itself, but it is the summation of all these little things that are helping some.
I did have a thought of another possible little thing. But a question please. When yall are using your car a/c out there is there enough humidity in the air to cause any drainage of water from the a/c unit? You probably know what i am thinking.
olddragger

 

excuse my sentence structure ---the wife gave me decaf diet coke this a.m.
OD

 

The slight separation actually causes the air before the radiator to come to a complete halt. Quite the opposite of what you are trying to accomplish.

No, it usually doesn't.
Even if it did, the water isn't particularly cool or in any great quantity - evern if you do live in a humid location