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For anyone interested in optimal Intercooler, Radiator and Fan installation...
Over the years I've seen many threads asking the best/correct way to fit a FMIC, slimline fans and rad combo and there's always mixed responses/opinions.... Fans then IC and rad, IC then fans and rad, IC, rad then fans, etc..
A couple of weeks ago I was mapping an RST with an Airtec IC, Spal fans and Airtec radiator... fitted in that order, the setup was far from optimal so I thought I'd share my experience with you and try to explain why it wasn't good and show how to do it better, hopefully giving anyone that might need to know some useful info!
The first issue I had was high intake air temps (IAT, ACT, MAT), once the car was up to normal running temperature it was at 35c and after only three or four full load WOT runs it was at 60c and detonating like mad, even cruising at 50mph in 5th to let it cool down only brought it to back 55c.... this of course was terrible! There was no way to map around such high temps and I ended up with only about 16psi of safe boost which was very disappointing as the car had so much more in it.
The second issue was coolant temperature, it was hitting 120c and struggling to come down without the use of the cabin fans!
It was obvious at this point that airflow to both the IC and rad was not good!
So here's the problems...
First off there was very little IC surface area exposed to full air flow, just the small area you can see though the upper opening in the bumper, the lower one just exposed the end tank which is no help at all.
Then having the fans in-between the IC and rad creates two problems, air will always take the easiest route so having a huge gap between the IC and rad means what air flow you do have will take any other route it can instead of going through the fans and rad, the fans themselves actually cause a restriction blocking air flow to the rad (Remember your fans do nothing to aid cooling other than when your car is stationary or barely moving).
In addition to those problems the fins on the IC run top to bottom and the fins on the rad run side to side effectively blocking each other if they were installed back to back (this is crazy as they are both Airtec items and should be designed to work together?! ).
Finally the bonnet has been raised to facilitate using an EFI inlet on a Zetec and this totally ruins the airflow through the engine bay (No it does not aid cooling), again the air will take the easiest route out of the bay basically avoiding the rad as it's much harder to flow through than just going around and out the back of the bay.
The most efficient install (and how you'll find it on most OEM cars) is to have the IC almost flush against the rad ensuring the fins line up so that air can flow through both uninhibited (using draft excluding foam/tape to seal the sides and top and bottom where they line up makes a big difference too, but most RST IC/Rad combo's don't allow for this as they are not the same size), then install the fans on the back of the rad creating an area of low pressure ensuring that air is sucked through both the IC and rad, ideally a fan shroud would be used but I've not seen anyone that offers them.
Here's a picture showing what I mean, it's not for an RST and it's not perfect as about 25% of the rad will see no airflow when relying on the fans but you get the idea.
A heat shield of some sort to protect the fans from the turbo may be needed if you do not have much clearance (most don't), heat tape, turbo jacket, etc.
I hope this is helpful to some of you seeing high temps (both coolant and intake air) or to anyone about to install a FMIC etc.
With the bonnet shut properly most cars can actually get away with sub-optimal installs but it's still good to know how to do it for the best results!
I've a pace rs500 style cooler at the minute with a standard radiator twin spal fans on the out side ..temps are bang on ..but im changing next month to airtec radiator and IC this thread now has me worried.
My old ZT Cabby was also within acceptable limits with a Radtec IC, fans and then copper rad and lots of cars I tune are ok too with similar setups.
But it's always good to know how to do it better if we can, lower intake temps means we can run more boost and more ignition advance.... which of course means more power! All whilst keeping the car cooler and stressing components less
GRS or Radtec are good, in the example above the Airtec one is pretty poorly designed so I wouldn't use that but so long as the fins run left to right like the rad it's more about how you fit it, trying to get good airflow through everything.
I've a pace rs500 style at the moment on my car and its good with standard rad ..but I'm sticking the turbo over the box so I need a new intercooler that's on the right inlet side ..as the pace 500 is a reversed charge carrier ..ive got a brand new airtec rad to use ..im unsure wether to order airtec cooler or not now .
It is but I need a another cooler as said above I'm sticking the turbo over the box and I've rs16i modded inlet so needs to be the other side other wise I'd have kept it.
karl
you say having fans on the inside so we can run more boost and run cooler
im running 30 psi and have low water temps
never had overheating or running hot problems,apart from when i tried to use 1 8" fan!
mine will sit in traffic all day
what is the correct coolant temperature for a zt once the car is up to temp? mine seems to run a bit hot and the fans seem to kick in a little bit late!
karl
you say having fans on the inside so we can run more boost and run cooler
im running 30 psi and have low water temps
never had overheating or running hot problems,apart from when i tried to use 1 8" fan!
mine will sit in traffic all day
Not the fans specifically mate no, simply that having temps closer to optimal is better than having them near the higher end when it comes to extracting power, why have your air at 45c when you can have it at 30c?
The same applies to the fans being on the back, it's a better setup and why OEM's mostly do it this way, why have them at the front restricting air flow if you don't have to?
Yours and many others as I said above are fine with less than optimal setups.... But it's always good to know how to improve things if we can
what is the correct coolant temperature for a zt once the car is up to temp? mine seems to run a bit hot and the fans seem to kick in a little bit late!
For thermal efficiency around 90c... Fans can come on anywhere from 100c-110c depending what your tuner has chosen.
If you're on the old CVH stat housing and fan switch you can get a couple of different temp ones.
For thermal efficiency around 90c... Fans can come on anywhere from 100c-110c depending what your tuner has chosen.
If you're on the old CVH stat housing and fan switch you can get a couple of different temp ones.
In that case mine is perfect I assumed the fans should come on a bit earlier then 100c. I think iv got the wrong temp sensor for my clocks as my clock reads just under the red but my rectech gauge says it at 90c
The gauge on the clocks can and often is miles out, the needle can just be pulled off and put back anywhere so there's a good chance it isn't correct all these years later.
But if your other gauge shows 90c then it's all good mate
I've got a MSD uprated fan switch and a 82c thermostat to fit to fit when I bang the new rad on .. I think ill move the fans to the back aswell.
Yeah they come on a few degree's earlier than standard (which I think is 110c IIRC) worthwhile upgrade.
Don't forget to make sure the fans are sucking and not blowing from the back! Dropping a small light piece of paper (Cigarette paper will do nicely) in front of the IC when they are on will soon show you which way they are going as it's sometimes hard to tell with just your hand.
Slightly off topic but with the intercooler/fans/rad I've normally been alright for temps although my bumper has been opened up somewhat, however I have murder with fan switches, after a while they start coming on at a lower temp then they won't switch off.
Just bought one from Burton power with a higher switch on temp but destroyed the gearbox before I had the chance to test it.
Good info. What about chargecoolers? Aren't they better suited to rst's?
IMO On an RST You do not gain anything over a properly installed IC but you have a lot more plumbing and of course another radiator and water pump etc to find space for.
Originally Posted by studabear
Slightly off topic but with the intercooler/fans/rad I've normally been alright for temps although my bumper has been opened up somewhat, however I have murder with fan switches, after a while they start coming on at a lower temp then they won't switch off.
Just bought one from Burton power with a higher switch on temp but destroyed the gearbox before I had the chance to test it.
Opening up the bumper will make a big difference as you can imagine.
Get Rick to install a relay and use your ECU to switch it on/off Stu, job done!
Got a relay in and the wiring for fan control, it doesn't work as that helmet that built the ecu has put a incorrect component in the circuit. My pal is gonna sort it, its on the list of little jobs lol
Some good info here, I'm replacing my airtec fmic with the latest grs one. Currently got airtec ic fans and rad on my s2 and coolant temps are great. Use an aftermarket gauge and ive never had it above 92 as the fans kick in early with msd fan switch and wiring loom. My charge temps are high and I can only run 15psi as any more and it will det at high revs. I've modified my ic and radiator brackets so the ic has some of the core showing at the bottom of the bumper and it's moved all the way over to the drivers side and I've moved the rad to the passenger side so it has a fair bit of core showing through the bumper. Just wondering is it possible to put the fans on the back of the rad on an s2 as the turbo and actuator are extremely close to the rad?
It doesn't run hot per-se, but higher than I'd like when giving it a kicking. I have a low temp fan switch from MSD and the fans kick in and out like they should. It's never got scary high, but I'm sure it could be better. When cruising the temps are really low, bottom of the gauge, when caning it, 3/4 of the way up the gague. It's putting me off doing track days so I'd like to try something.
Ive always wanted to change the layout for better cooling. The only worry I have is all that heat from the turbo melting/killing the fans if they're on the back. I guess you have never come across that?
Just to add, I'm an Airtec fan (see what I did there ). I like their products and they do work well.
I heat shield of some sort will help protect the fan nearest the turbo as they are plastic and may suffer a bit.
I've not had one melt no mate, by the time you come to a standstill you should have let everything cool down a bit anyway and when your in motion airflow should protect the fans a fair bit.
I imagine if you pulled up to a stop with a glowing turbo and manifold and just shut off then the fan nearest the turbo could get a bit soft?!
It's been a while since I've installed anything using standard pipework but if it doesn't reach then just your usual joiners and silicone hose to make things a bit longer mate.