Would removing the undertray help the radiator in FMIC applications?
 

I was thinking that with the open space below the airflow after the FMIC will go the path of least resistence - the open space.

Also, the radiator could get fresh air from that open space. Sure some of that will come from the FMIC, but I suspect that much of the post-FMIC air will be diluted with regards to air temps.

It might help to set the fan to kick in at 85C.

This is just a thought.

the air flow would be out the bottom so the radiator would get even less flow through its core...imo since I've never tested it:)

Tim

ask ivan or cory about this one, I have thought of a plan much like this one and wounder if it would work? BTW corys is fc so might make a difference

Most people end up making some ducting to bring air from under the FMIC back to the radiator. The TurboStreetFighter FMIC used to come with a setup just like that and it was pretty effective.

The best judgement I can make on that is that any sort of performance designed ducting will make it better in some way. Those of us with Vmounts can't use the stock undertray because its mounting arms hit the radiator. I'm working on my heat shields right now, but I think I will eventually make some sort of custom ducting to smooth out the underbody flow and vent it appropriately where the fans are aimed at the ground. With a front mount, I'd imagine it would be a good idea to have some scooping shields to aim air up into the radiator and it'd also be a good idea to have some sort of ventillation setup to get the hot air routed out to a better place than the rest of the engine bay. I think designing that idea would be harder on a front mount than a vmount just because the vmount pretty much routes the exhaust air directly out of the engine bay.

just make a duct thing for it...

right now its 80 in NY...driving my car i was seeing 150 -160 on my digi at 60mph

its to COLD....so if your really nuts about having any temp over 180 make a ducting system for it

ok for putting around with fans on, but fans are not designed for sustained high power runs (track).

stock undertray is already by-level. For fmic, could use this airway, with openings in front spoiler, to bring extra fresh air to rad. I think passage is used to cool oil pan now .. not sure how effectively. the current exit area would be sealed, and the false bottom would terminate aft the fmic, and sealed to it.

ccarlisi did a nice mod to the undertray to flow some air to the rad under his fmic. search for his user name and click to get to his web site.

no! quite the opposite actually.

i've FCs and FDs overheat while driven under hard conditions when you remove the undertray, lots worse when you have a FMIC.

For better cooling with any IC configuration;
1) get rid of those stupid nose intake corner pieces.
2) make blocking plates for the holes in that area.
3) install lower lip shark mod.

See pic below.

Like Tim said,
the undertray forces the air through the radiator. If you remove it, the air through the FMIC will continue in the path of least resistance, and thus you will have minimal ram-air through the radiator. You will still have some flow due to the fans, but under certain conditions (tracking) it would not be sufficient.
If you remove the undertray, air WILL NOT get sucked up from under the car and through the radiator.

I've run my fmic for about a year now with no undertray and the temps have decreased if any.
But... I also installed a PWR radiator to though. The only issue I see is that the engine bay gets dustier quicker.

BATMAN, I can't believe you're even trying to pass yourself off as some genius posting this. shit.

I believe you're also the moron trying to pass yourself off as the genius behind the buttplugs fiasco of last year.

In fact, I think you're just a Domino Pizza guy b/c that is the only reason for your car having 200+K miles.

so yeah, all things considered, ir un no underbelly, and see no adverse affects to my temps

i will be fabbing ducts though, so i'll post results when done

That doesn't mean your cooling capacity would not be better if you were to add an undertray, it just means you have enough cooling capacity right now. If you were to seal it properly you'd have even more.

Seems like we have one guy that doesn't have any problems........

and another one.

The car will run just fine with only 2 quarts of oil in it too. Does that mean it's optimal?

Still trying ur little jabs at me?

Who was that other guy that tossed u around in the other thread that u failed to rebuttal intelligently?

U should spend time making ur FERRARI avatar look better.

For handling due to less weight ;)

What guy, and which thread? Your Ferrari avatar is a bit blurry, Poman...LOL :biggrin:

https://www.rx7club.com/forum/showthread.php?t=327976

Enjoy :D

That's pretty incredible with a 180F tstat bro. :rlaugh:

Holy Moses, BATMAN! That's one long thread. I got bored after page 4. Anyhow, looks like typical Po-Man stuff. Peace :peace:

Looks like Po-man Ferrari is starting to build mucho "respect" amongst the community.

:D

Just curious as to how you would know this? I have figured that with a SIGNIFICANT amount of air being held off at the front of the car due to the front mount ic that it would make MORE sense to leave the stock undertray off. The only thing that I could see better than this would be a custom undertray which isn't exactly easy to do for a lot of people, I have no resources for this... now if somebody was to make one for my set-up then that would be "Optimal". And have a vented hood as well.

You know, not everything on the car has to be perfect if it is already running very fine. IMO

It's crossed my mind about the ducting issues (not the undertray) at speed. If the new 99 spec front bumper with it's larger radiator and I would guess similar ducting as our cars (undertray openings, foam around the radiator), then there is a finite amount of air that can pass through the radiator. The reason for the front air damn redesign was because of this. There was too much air going into the mouth and not going through it fast enough when at speed that it was spilling back out the front of the mouth and under the car causing turbulence. They redesigned it to channel the air around and to the side with a little of the canard effect on the sides.

Comments?

Tim

like the way I slipped the wrong spelling of dam in there:)

Tim

I have the Blitz FMIC installed with the stock radiator and removed AC Condenser. I noticed a large difference in average temps cruising and running it hard. I was so excited to show the local car guys my intercooler that i didnt bolt the undertray on. My fans were never off!!!! I was always idling at 96-100C put the undertray on and total difference. 85-93C average temps. The undertray is a necessity for cars like mine.

Interesting find:

Today I re-installed my 99-lip and left the undertray off.

The water temps shot up to 105-110C!!!

Then I installed the undertray with the 99-lip and temps dropped to 85C.

With no undertray and 99-lip there wasn't that much difference in temps. It would hover around in the mid to high 80's.