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HardHead93
It got a little warm today in southern New Mexico so today was the first day I drove the 3sgte swapped Celica in stop and go traffic with the AC on. Normally without the AC on, the engine temps bounce between 189 and 199 degrees F. When I turned the AC on it climbed to 209 degrees in the course of 5 minutes before I turned the AC off. Once I turned the AC off the temp quickly dropped back into the normal range in about another 2-3 minutes. I am reading the temps off an aftermarket water temp gauge with the sensor on the upper radiator hose. Below is a picture of the type of gauge I am using. It is a Glowshift MaxTow water temp gauge.


When that gauge reads 215 degrees the stock dummy temp gauge in the car starts moving towards the H. I am running an Ebay 2-row radiator with aftermarket fans and I have a FMIC. Should I keep the aftermarket fans or go back to a stock radiator with stock fans? Also, the Ebay radiator is pretty dirty from constantly taking it in and out of the car during the build process, could that be the culprit? Is there something else I should check on that may be causing the engine temps to climb with he AC on? Below is a picture of the 2 different radiators.


Is there really an advantage to running a 2 row radiator with a 3sgte?
Bitter
The stock fans will move WAY more air. The AC adds a fairly large heat load IN FRONT of the radiator meaning it's getting pre-heated air through it, that's why having high airflow is so critical when running the AC system AND trying to keep the car cool. I think swapping to stock fans will probably take care of the issue, but it would also be a good idea to clean the AC condenser and radiator with some AC coil cleaner per bottle directions.

Some cars have pusher fans on the AC, you could piggy back a single slim fan to the stock fans via a relay and mount it up front to blow inward (between the IC and condenser , there could be some airflow drop through the thicker radiator core, but that's a lot of added electrical load for possibly no gains in cooling.
HardHead93
QUOTE (Bitter @ Mar 17, 2017 - 8:49 PM) *
The stock fans will move WAY more air. The AC adds a fairly large heat load IN FRONT of the radiator meaning it's getting pre-heated air through it, that's why having high airflow is so critical when running the AC system AND trying to keep the car cool. I think swapping to stock fans will probably take care of the issue, but it would also be a good idea to clean the AC condenser and radiator with some AC coil cleaner per bottle directions.


So stock fans with the stock radiator? I tried to put the stock fans on the 2 row radiator and they do not fit.
Bitter
Cause the rad is too thick or the mounting studs don't line up?
HardHead93
QUOTE (Bitter @ Mar 17, 2017 - 10:35 PM) *
Cause the rad is too thick or the mounting studs don't line up?


The mounting studs do not line up. I broke one factory fan and had to go get a second one from the junk yard. I just put the factory radiator back in with the factory fans and it seems to be cooling really well.
Bitter
It shouldn't be hard to use some aluminum bar stock to make a bracket to bolt to the studs and then bolt the fans to the bar stock, should you later desire the bigger radiator.
HardHead93
So I ran the stock radiator with the stock fans yesterday and the heat issue during stop and go driving with the AC on got better but then I started having worse heat issues with sustained driving on the freeway. My water temps were climbing to 213-215 degrees F when before the highest they would go with freeway driving was 204. I think this is pointing to an air flow issue. If I don't figure out how to get more air to the radiator it doesn't matter what fans or radiator I am using. After doing some research and talking to a couple of people I know with turbo cars (they drive Honda Civics but I will forgive them tongue.gif ), it looks like the front mount intercooler is blocking air flow to the radiator.




When I installed the intercooler I kept the crash bar in place because the fog lights attach to it. A lot of FMIC installs on our cars have removed that bar. I can see that being a culprit for blocking air flow. Is that true? If I remove the crash bar, is there a way to mount the fog light brackets so I can keep them? The whole point of my turbo build was to have a more powerful engine but not at the cost of losing functionality (fog lights, cruise control, AC, etc.). As you can see from the first picture I also installed an additional bumper duct to help with cooling but it is not enough. I have switched back to the 2-row radiator because it seems to cool the best for the majority of the type of driving I do. Any ideas for fixing this problem would be greatly appreciated.
Bitter
I think you need to keep the crash bar, it's super important should there be an impact.

I would ditch the fog lights and move the oil cooler to one side in the fog light opening, should get enough airflow and small fan on a thermostatic switch could be attached if needed.
Then the next step would be to get the stock fans mounted to the 2 core radiator and open the area above the crash bar in the bumper so airflow can bypass the FMIC to the radiator.




You could also look into water spray systems to mist water through the FMIC or onto the radiator to add cooling on a demand basis, like maybe trigger it off the radiator fans so when they turn on you get a mist of water sprayed over the radiator for additional cooling. Evaporating water off the IC and radiator can dump a bunch of extra heat, but it would need to be a pulsed spray, like 1 second on, several seconds off. They make systems for that, but it's been years since I read about them.
HardHead93
QUOTE (Bitter @ Mar 19, 2017 - 12:54 PM) *
I think you need to keep the crash bar, it's super important should there be an impact.

I would ditch the fog lights and move the oil cooler to one side in the fog light opening, should get enough airflow and small fan on a thermostatic switch could be attached if needed.


Sorry, the picture with the bumper off is old. The oil cooler was removed when I went from a 5sfte to a 3sgte. I will look to widen that vent I cut in the bumper and potentially install another. I agree, the crash bar is very important, I will keep it. Ideally I would like to get this bumper.


It has extra vents in it and would solve my air flow issues. The problem is I am not too sure about the Duraflex brand's quality and I hear a lot of those bumpers tend to crack really easy.
Bitter
Ever seen a GT4 front bumper?
http://www.6gc.net/forums/index.php?showtopic=63523
Look at how much more open space there is and that big extra opening up top, you need something like that.
Box
Anything under 240 is within operating spec on most any modern engine, so if it only gets up to 215 you're over worrying. Ideally you're in the 185-210 range on most engines. Thing is though the best place to read water temperature is in the head since it's most accurate, so odds are you're higher than what you're currently reading. You could go to a GT-Four bumper and hood as well as the TMIC if you could find one, it worked for every factory GT-Four so you know it'll work for you. Though many do fine with a FMIC and the GT-Four bumper and hood.
HardHead93
QUOTE (Box @ Mar 19, 2017 - 8:47 PM) *
Anything under 240 is within operating spec on most any modern engine, so if it only gets up to 215 you're over worrying. Ideally you're in the 185-210 range on most engines. Thing is though the best place to read water temperature is in the head since it's most accurate, so odds are you're higher than what you're currently reading.


When i was running a standalone on my 5s and could pull temp readings right off it, I had this sensor/gauge in place and it was pretty close to the same as what was coming off the stock temp sensor on the coolant neck (my gauge was reading 1-2 degrees higher). On the 3s the stock sensor is in the same place on the coolant neck that comes off the cylinder head so I am probably in the same boat. What ever my gauge is reading is pretty close to what the ECU is seeing. It is good to know that the temps (around 215 degrees F) I am seeing could have me worried for nothing.

QUOTE (Box @ Mar 19, 2017 - 8:47 PM) *
You could go to a GT-Four bumper and hood as well as the TMIC if you could find one, it worked for every factory GT-Four so you know it'll work for you. Though many do fine with a FMIC and the GT-Four bumper and hood.


I already have a custom vented hood.


I like the GT-Four bumper but it seems like everyone is doing that conversion who has a 6th gen Celica. I would like to use a bumper that gives a different look than everyone else but still provides the venting I want. Is there any reputable company that makes a quality aftermarket bumper of the style I am looking for? I am planning to repaint the car later this year and I would do the bumper then.
slavie
Stock fans are better - they have scoops to pull the air from the entire surface of the radiator vs the aftermarket coolers on the 2-row you have. I mean, just looking at those fans on alum rad, they do not apply to at least a third of the radiator.
If you could fabricate a way to attach stock fans, that would of course be your best bet.

Aside from that, you either need to increase inflow, or reduce the pressure on the back so that the air can outflow more easily. First would require chopping up the bumper or getting an aftermarket one. I know you said you don't like the GT4 bumper, but those are really good - crash bar is much narrower (if you get the whole front bits, not just the cover) and you have a lot more air inflow.

Another idea is to look at your engine splash shields (under engine covers). A lot of people junk them thinking they block airflow. But, toyota put it there for a reason - smoother airflow under the car will create lower pressure under the car and allow the air from the engine bay to escape more easily. Removing the under engine covers creates turbulence, and may make matters worse. You can search around the internet and there are threads where people measured the temp differences and say a drop in temps WITH the covers.

Finally, your FMIC looks pretty restrictive. Not sure how much you can do here, but just pointing it out. GT4 A2W intercooler is more like a regular radiator rather than having flat bars like the A2A FMIC.

Hope this helps.
Box
The Duraflex bumper you posted earlier is a knock off of the C-ONE bumper, but an authentic C-ONE bumper is hellaciously rare.
HardHead93
QUOTE (Box @ Mar 20, 2017 - 3:49 PM) *
The Duraflex bumper you posted earlier is a knock off of the C-ONE bumper, but an authentic C-ONE bumper is hellaciously rare.


Ahh man! I really like the look of that bumper. mad.gif
Box
There out there, but usually they're overseas and shipping is a fortune. That and it seems like most don't know how to package anything so it ends up arriving broken more often than not. You could do like some people have done and combine the GT-Four and facelift bumper, "SS-IV" is usually what it's called if memory serves correctly.
Bitter
I still think if you dump the fogs and put two air scoops there with some duct you could get air up to the top of the radiator bypassing the FMIC and might be OK, certainly cheaper to try that out than to get a new bumper and paint for the new bumper. if it doesn't work then you've at least tried.
Box
I want to say someone used to make vents for the Celica specifically you cut out the regular bumper and then they fit in place over the cutout, they were sorta in a GT-Four style.
HardHead93
I widened the opening on the carbon fiber bumper vent I installed. It seems to provide the additional needed air flow that bypasses the intercooler with the AC on. The water temps don't seem to be climbing as high anymore. That was in 90 degree weather. The true test will be when we start having 100+ degree days during the summer.
Box
Or in order to satisfy my OCD and provide additional cooling you could install a second vent mirrored to the first one. tongue.gif
Bitter
I agree.
HardHead93
QUOTE (Bitter @ Mar 25, 2017 - 4:56 PM) *
I agree.


To be safe I think I will order another one and put it in.
HardHead93
This morning I got around to adding the 2nd bumper duct so I can get air flow to bypass the radiator. The cooling is a lot better.


It was pain in the butt because I had to measure over and over again to ensure it lined up with the other duct before I started cutting. It came out good, phew!
Box
Much better. thumbsup.gif
Bitter
If it ever stops working as good all you need is some nasal spray.
HardHead93
QUOTE (Bitter @ Apr 1, 2017 - 7:31 PM) *
If it ever stops working as good all you need is some nasal spray.


Now that you say it, it does look like a big nose. I hope it doesn't need an inhaler. biggrin.gif
Box
If you want giant nostrils on a car look no further than the '98-02 WS6 Trans Ams and Formulas. tongue.gif
HardHead93
It has gotten a lot hotter here in southern New Mexico over the last few weeks and the AC, engine temp problem has come back. When I drive around town especially on the freeway with the AC on the water temps climb into the low 220s and would probably go higher if I did not turn off the AC before it got to that. As soon as I turn the AC off the water temps drop back into the low 200s within a few minutes. Also when the AC is on it blows cold but will get warm (not hot but definitely not as cold as it should be) for a few moments before getting cold again. This leads me to the following conclusions:

1. This problem occurred with the stock and 2-row radiators which leads me to believe the radiators are fine.
2. The car runs in the 180-205 range when the AC is off so it is not an air flow issue.
3. Since the problem goes away immediately when I turn off the AC, this leads me to think it is something with the AC condenser. Maybe it is clogged or malfunctioning.

To be safe I am going to replace the radiator with another brand new 2-row one, replace the AC condenser, and clean the intercooler. If this does not correct the problem I do not know what to do.
Bitter
Sounds like the system pressure is going high due to lack of cooling, is it missing fins? My 7G Celica condenser was missing most if the fins in the lower 1/3 of it, replacing with a good new Denso unit restored my AC to blowing ICE cold at all times. An over charged AC system can cycle off due to high pressure as well, under charged will blow extra cold or not work, but at the expense of causing low lubrication to the compressor due to lack of oil flow in the system. Which leads to the least happy possibility, there's debris in the system causing high side pressure to go too high.

But AC is a heat pump. it pumps heat from the cabin to the outside. If the system isn't working correctly because of a charge level issue it won't be moving the heat. It sounds like the AC is working properly and overloading the cooling ability of the radiator OR the FMIC is introducing too much heat into the condenser and radiator for them to all work properly. It's a shame you can't move the FMIC forward into the lower mouth and divert the air passing through it downward and out before it hits the radiator. That would still be blocking too much airflow. I think the GT4 bumper may be the only fix, that or figuring out some kind of dual SMIC setup like some VW's use.
Box
I'd check the condenser and system pressure before I start replacing things. Another thing would be to make sure your radiator fans are kicking on when the A/C is turned on, I forget how exactly it works for the 6th gen but either one fan should turn on or both will come on as soon as the A/C is turned on. Not sure why that wasn't mentioned ages ago, but it's easy enough to double check.

My brother's Audi A4 has the dual side mount intercoolers, I thought it was kind of strange to do on an engine with a single throttle body but I guess it was done for space and cooling constraints. Shouldn't be too hard to replicate if you grabbed everything off a totaled VW/Audi. Could possibly mount them where the foglights are. I remember you saying you didn't want a GT-Four bumper so it might be the way to go.
HardHead93
Everyone, thanks for all the info. Based on what everyone has said, I plan to do the following:

- Replace the condenser and get the system recharged to the proper pressure
- Replace the 2-row radiator and attach stock radiator fans to it (Does it matter if I go with a generic Ebay one or Mishimoto, they look the same?)
- Replace the ATA with a WTA intercooler. This will eliminate my intercooler piping and allow me to mount the stock radiator fans. Also heat exchangers do not restrict air as much as ATA intercooler.
- I have an exhaust leak on the manifold gasket so I will fix that since I will have access

I looked around for a GT4 bumper in case all of this does not work and have come up with nothing. I will be gathering the parts over the next 2 weeks to do this. Is there anything I missed? Oh yea, and my intercooler fans kick on fine when I turn the AC on.
Bitter
I think dual SMIC is a better choice, if it's possible.
HardHead93
QUOTE (Bitter @ Apr 11, 2017 - 8:28 PM) *
I think dual SMIC is a better choice, if it's possible.


Why do I need dual side mounts? Wouldn't a single one be fine? I have only 1 intercooler pipe. I believe the dual side mount is for a V style motor with twin turbos. Plus MR2s run a single side mount on their 3sgte.
Bitter
To equal the area of your single large FMIC I would think you would need dual side mount?
Box
The A4 is an 2.0 I4 and has the dual side mounts, you run them in series. Here's a picture of one with the front end off so you can see them:
Bitter
And you can put small puller fans on them to keep heat soak down at lower speeds between pulls or on the dyno.
HardHead93
I am still not convinced it is the intercooler causing the problem. There are plenty of people who have done 3sgte swaps with FMIC and have had no problems. Here are some photos of when Tweak'd used to do engine swaps and they were all FMIC (without GT4 bumpers).





Also, also there are 2 other people on this forum (DarkDeath and ILoveMySilly97) who just recently did 3sgte swaps with FMIC and I have not heard them having problems like this. I really think something else in my system, like the radiator or the condenser is causing the problem. I think before I start going down the route of swapping intercoolers, I am going to replace those 2 parts. Plus, the side mount thing will not work for the Celica on the passenger side unless I remove the windshield wiper fluid tank.
Bitter
Paahhhh you don't need washer fluid. Well not there. You can put a generic tank anywhere.

Sounds reasonable. Maybe boil the thermostat to make sure it's fully opening.
HardHead93
QUOTE (Bitter @ Apr 12, 2017 - 1:18 PM) *
Paahhhh you don't need washer fluid. Well not there. You can put a generic tank anywhere.

Sounds reasonable. Maybe boil the thermostat to make sure it's fully opening.


I am about to order what I need. Does it matter if I get a Mishimoto 2-row radiator or a generic one? They both look the same. The thermostat is under warranty so I will just replace it. I am going to hold off on the intercooler for now.
Box
A lot of people remove A/C as well, so they wouldn't have a problem in that regard. As far as the radiator goes after looking the generic eBay specials and the Mishimoto do look strikingly similar. Not saying it's the case but odds are they're both made by the same factory and the best ones get the Mishimoto branding while the others get sent to whatever seller on eBay or Amazon. It's hard to tell from the pictures, but it does seem like the Mishimoto ones have cleaner welds. If it were me I'd look into the Koyo Racing radiator part# R1958.
HardHead93
QUOTE (Box @ Apr 12, 2017 - 5:28 PM) *
A lot of people remove A/C as well, so they wouldn't have a problem in that regard. As far as the radiator goes after looking the generic eBay specials and the Mishimoto do look strikingly similar. Not saying it's the case but odds are they're both made by the same factory and the best ones get the Mishimoto branding while the others get sent to whatever seller on eBay or Amazon. It's hard to tell from the pictures, but it does seem like the Mishimoto ones have cleaner welds. If it were me I'd look into the Koyo Racing radiator part# R1958.


I didn't even think about that brand. It looks like the stock radiator fans mount directly to this radiator. The following thread says so:

http://www.6gc.net/forums/index.php?showtopic=61443

Can you confirm if that is true because if that is the case, I will definitely go with that radiator?
Box
From all the listings they say the Koyo despite being a racing radiator is meant to be 100% direct fit and uses the stock fans, the only thing not direct fit is the radiator cap and you need one of their caps but that's not a big deal if everything else is 100% o.e. fit. Personally I'd trust Koyo over Mishimoto or a generic eBay just due to the fact Koyo is an o.e. part supplier, that and the Koyo looks nicer made for the same price as the Mishimoto. Here according to their quality page they state every radiator is made to use all o.e. mounting locations and fans: http://koyoradracing.com/about/our_quality.asp
HardHead93
QUOTE (Box @ Apr 12, 2017 - 7:13 PM) *
From all the listings they say the Koyo despite being a racing radiator is meant to be 100% direct fit and uses the stock fans, the only thing not direct fit is the radiator cap and you need one of their caps but that's not a big deal if everything else is 100% o.e. fit. Personally I'd trust Koyo over Mishimoto or a generic eBay just due to the fact Koyo is an o.e. part supplier, that and the Koyo looks nicer made for the same price as the Mishimoto. Here according to their quality page they state every radiator is made to use all o.e. mounting locations and fans: http://koyoradracing.com/about/our_quality.asp


SOLD!
Box
I found a few on eBay in the $270-280 range, but main thing is finding an authorized retailer so you get all of your warranty. At any rate if it were me I'd go with the Koyo over the others.
HardHead93
QUOTE (Box @ Apr 12, 2017 - 7:59 PM) *
I found a few on eBay in the $270-280 range, but main thing is finding an authorized retailer so you get all of your warranty. At any rate if it were me I'd go with the Koyo over the others.


I found a retailer selling one with the radiator cap for $304.99. It also comes with the warranty. I just made the purchase along with the condenser. I hope to get all this swapped out when it comes in. Thanks for the info, I would have never thought of looking at the Koyo radiators had you not said something.
Bitter
It would be wise to have a shop evac the AC system for you, then also have the shop recharge it correctly as well. If the receiver/dryer is old it should be replaced in the system as well.
Box
QUOTE (HardHead93 @ Apr 12, 2017 - 10:10 PM) *
QUOTE (Box @ Apr 12, 2017 - 7:59 PM) *
I found a few on eBay in the $270-280 range, but main thing is finding an authorized retailer so you get all of your warranty. At any rate if it were me I'd go with the Koyo over the others.


I found a retailer selling one with the radiator cap for $304.99. It also comes with the warranty. I just made the purchase along with the condenser. I hope to get all this swapped out when it comes in. Thanks for the info, I would have never thought of looking at the Koyo radiators had you not said something.

Cool beans. No problem, I'm not sure why but I all of a sudden had remembered Koyo made racing radiators for the 6th gen GT among a few other Japanese cars.

Ditto on having a shop pull a vacuum and recharging it as well as replacing the drier/accumulator, personally with most cars the drier is cheap enough that it only makes sense to replace it every time you have the A/C recharged.
slavie
"While you're there" jobs can be a real time hog, but, while you're there, think about replacing the seals in the AC connection points, at least the ones you touch. If your current refrigerant levels are really low, it must have escaped somewhere, which could well be the seals. Not sure if the new condenser comes with seals, but they're a few bucks anyway.

And yes, replace the dryer - they act like filters in the AC systems, and really are relatively cheap.

You can DIY AC vacuum, but need some tools (which can be loaned out at auto stores) and knowledge, so up to you. To discharge it first before you start taking parts though, a shop has to evacuate the system, definitely not a DIY.
HardHead93
Just about all the parts are in and I am getting ready to start replacing the AC condenser and radiator. I am going to have to take off the intercooler to get to all the parts on the car. This brought up a question. Since I will have the intercooler off, is it a good idea to put a puller fan on it? If so should I wire it with the rest of the radiator fans or have it turn on by some other method?
Bitter
Wire it to an IAT with a fan controller kit so it comes on at your target IAT.
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