1G Fan size help.. my coolant temp is out of control

[enriquez2000]

I dont have an fmic yet.. i have a koyo radiator with some 13" slim fan that was given to me with it.. no idea what cfm its pulling.i still have the ac fan in place so it comes on in an emergency as intended.

I drove home 2 nights ago(97* out) and check engine started going on and off after i got into atop and go traffic. Plugged in lap top and coolant temps were 240. My gauge in car never moved beyond halfway so since i needed to replace it i went ahead and got a new thermostat to put in while coolant was drained.

Well today it was 85... had laptop on the whole drive to monitor. Temps got to 223 once i hit stop and go again.

At this point i feel the fan isnt pulling enough so im wondering what i should get...

There is a 1710 cfm 13" spal, but that leaves little room for a second fan. I saw some 12" spal that are 1200cfm i think. 2 of thise would net me 2400cfm.

Ive heard bad things about the mishimoto kit with shroud but no personal experience.

Basically i want to buy only once and not do the trial and error thing so im looking for solid input. Ideally id like temps no higher than 205 after the fmic goes in. But definitely 240 with no fmic is bad news already.

 

[donniekak]

You can set up fans on a 1g to come on at a certain temp with link. You just have to wire them into relays connected to the fps, and egr solenoid outputs. Mine come on at 180, and 190. I run a 165 thermostat. Most of the time in Phoenix I can stay under 200*.

 

[Dsmkauai]

^^ Nice to know thx bro

 

[ceedawg]

I made one of these for my car out of abs plastic works like a charm to kill turbulence so that the fans and the air coming in can properly cool the cores. It goes from the bottom lip of the front of the bumper to just behind the radiator. Not hard to make at all. Wish i had posted pics. PS i actually tucked it in the front lip of the bumper under the fmic. Came out so nice it looks factory.

http://m.ebay.com/itm/APR-Mitsubish...ind-Splitter-2008-Up-/231973600616?nav=SEARCH

 

[motomattx]

Being that its summer lose the thermostat for a day to see if the car is capable of cooling with the current cooling system, you wont even lose any coolant if you pull it when its cool.

 

[miguelmcv]

If you have link you can set them to turn on at any temp you want, including having them on at all time, it doesnt matter if its a 1g or 2g, the system is the same( link).

 

[ceedawg]

I would.never go without a thermostat just take care of whatever issue is keeping the car from running cool. No.bandaids!!

 

[donniekak]

If you have link you can set them to turn on at any temp you want, including having them on at all time, it doesnt matter if its a 1g or 2g, the system is the same( link).

The 1g system isn't controlled by the Ecu in the stock setup. It's controlled by a thermo switch in the radiator and the ac switch.

 

[motomattx]

Running without a thermostat is not a bandaid, the thermostat is largely for creature comforts such as heat and faster emmisions compliance, cars and every other engine existed for decades without them including modern motorcycles and atv's, back on subject though you can run without it for a day or two to see if your cooling system is capable of bringing the temps in line, it takes all of 60 seconds to pull it out and no to little coolant loss and its FREE best of all.

 

[lasershark]

Why not just run then always on? That's how I run mine and have for over 10 years

Just curious... Same fans and they've held up for 10 years?

 

[enriquez2000]

If it was a cooling system issue i doubt i would see temps dropping so well while driving. In the morning i can watch them drop from 190 to 174 by staying on the county roads with no stopping.

Stop and go is the only issue im having at all. Even in an 85* day on county roads with no stopping ill be down to 190. As soon as i hit city traffic things start going up. Havent hit 240 like i did but its also not 100* again. Highest ive seen is 216 since thermostat and making ac fan come on with the other. Again its 85 out not 100 though.

 

[ceedawg]

Running without a thermostat is not a bandaid, the thermostat is largely for creature comforts such as heat and faster emmisions compliance, cars and every other engine existed for decades without them
including modern motorcycles and
atv's, back on subject though you can run without it for a day or two to see if your cooling system is capable of bringing the temps in line, it takes all of 60 seconds to pull it out and no to little coolant loss and its FREE best of all.

You leave out a whole lot as to why these cars,fuel injected cars should continue to run with thermostats!
Here is a quote
if you run too cool, you'll have the problem of running in open loop all the time...you'll be lucky if you get 12 mpg.
The arguement on the pros/cons has gone on for years and would take up volumes. That said, the cars were designed to run with a thermostat, and it won't do any good to run without one as far as any noticeable advantages...personally, I run a 180...it gets the oil hot enough to burn off any condensate and other crud, you have acceptable heat for the passenger compartment, and I feel its a nice balance of the run it hotter/run it cooler arguement...but that's just me. Hope this helps!!

 

[Dsmkauai]

Just curious... Same fans and they've held up for 10 years?

Ya and there the oem fans , it's actually been longer I got my gst back in 99 . I've also been running my slim fans this way with no issues for a few years now too.

 

[motomattx]

You leave out a whole lot as to why these cars,fuel injected cars should continue to run with thermostats!
Here is a quote
if you run too cool, you'll have the problem of running in open loop all the time...you'll be lucky if you get 12 mpg.
The arguement on the pros/cons has gone on for years and would take up volumes. That said, the cars were designed to run with a thermostat, and it won't do any good to run without one as far as any noticeable advantages...personally, I run a 180...it gets the oil hot enough to burn off any condensate and other crud, you have acceptable heat for the passenger compartment, and I feel its a nice balance of the run it hotter/run it cooler arguement...but that's just me. Hope this helps!!

These cars were also designed to make no more than 210 hp, with more hp comes more heat and more cooling system mods to deal with that heat! for that matter Magnus Racings car was designed to run with a thermostat also, however it doesnt have one last time I checked. No car in the summer is going to run in open loop due to not having a thermostat, thats simply ridiculous to even suggest, the car will still get up to full operating temp or better it will simply take 3 minutes or so longer to get it there, I have worked as a dealer tech most of my life I'm pretty sure that I know what I'm talking about here. When a car comes in for an overheating issue after the fluid levels are checked and a quick check for leaks the first thing that happens during diag is to remove the thermostat and take it for a drive to see if it still overheats, if it does then we know that we have a headgasket failure or a pump that is damaged in some way, if it doesnt then we know that we have a partially blocked radiator or worse, its a free easy way to diagnose the problem.

 

[GST with PSI]

You don't want the aluminum "box" type shroud like the one Mishimoto sells. The design is garbage, and they just hinder airflow at speed.

There's a reason the FAL shrouded kits are so expensive, because they are actually designed and constructed properly. Compare the design of a FAL shroud to the crappy Mishimoto one, and you'll see what I'm talking about.

Just use a combination of solid mounts and push ties if you can't use solid mounts alone to mount the fans. Your fans will work better that way, rather than mounted to a crappy aluminum box shroud.

 

[EvilGST]

These cars were also designed to make no more than 210 hp, with more hp comes more heat and more cooling system mods to deal with that heat! .

Not exactly. This would only really apply during a quarter mile pass, even then thats not going to be enough time to reach the limit of the factory cooling system. A 420hp DSM by comparison with standard compression will not produce any more heat just cruising and daily driving. Road racing is the only scenario I can think of where a high hp DSM will require increased cooling capacity.

 

[ceedawg]

And my car is 500+ awhp and I still have the thermostat. Im sure the 730hp Dodge Hellcat and 640hp Corvette Z06 have thernostats as well.

 

[enriquez2000]

I keep seeing head gasket and clogged radiator thrown around... this issue would happen at cruising and stop and go traffic i would assume. I am ONLY getting slow creeping coolant temps in city and dont overheat(other than the 100* day we had)

 

[godschylde777]

I keep seeing head gasket and clogged radiator thrown around... this issue would happen at cruising and stop and go traffic i would assume. I am ONLY getting slow creeping coolant temps in city and dont overheat(other than the 100* day we had)

You have a cooling system issue. I can guarantee this. Pull the radiator and have it flushed. Do a preasure check on the entire system. A blown head gasket would cause your issue. I have read this entire thread. They are telling you the same thing. I'm not trying to be a bone head, it's like you want them to tell you what you want to hear. There is something is wrong with your system. You are overheating without a fmic. Just check it before you buy anything else.

 

[Lou98GSX]

when i have an overheating vehicle at work this is how i approach it . first thing i do is put a scan tool on it and watch the coolant temp and wait till the thermostat opens . what will happen is the temp will go to maybe 200 and then drop down and then i know that the thermostat is working cause all the coolant from the radiator is now going in the engine . next thing is wait for the fan to come on and see if the temps go down or just sit there . if the temps don't go down and the fan is running then you could have a clogged radiator, bad water pump , blown head gasket or even a thermostat that is not opening all the way . very rarely you have a bad water pump but you can check it when the vehicle is cold you have the upper radiator ready to come off at the thermostat housing while another person in the car is ready to start it you then pull the radiator hose off and if the water pump is working your going to get a gush of coolant coming out of the hose . it's a little messy but it's worked for me . in my almost 40 years experience i have seen 2 bad water pumps where the impeller was not turning . plenty of radiators and head gaskets. reading your post and the issue you are having i don't think its a radiator or a water pump . i would rule out the head gasket and another thing is i don't know if the 1g is like the 2g where you have 2 speed cooling fans . it could be that your fan is only working on low speed and when you need the other speed it doesn't work . another thing i just thought of is check your heater core cause coolant has to flow through there and back to the engine .

 

[GST with PSI]

Running without a thermostat is not a bandaid, the thermostat is largely for creature comforts such as heat and faster emmisions compliance, cars and every other engine existed for decades without them including modern motorcycles and atv's, back on subject though you can run without it for a day or two to see if your cooling system is capable of bringing the temps in line, it takes all of 60 seconds to pull it out and no to little coolant loss and its FREE best of all.

You leave out a whole lot as to why these cars,fuel injected cars should continue to run with thermostats!
Here is a quote
if you run too cool, you'll have the problem of running in open loop all the time...you'll be lucky if you get 12 mpg.
The arguement on the pros/cons has gone on for years and would take up volumes. That said, the cars were designed to run with a thermostat, and it won't do any good to run without one as far as any noticeable advantages...personally, I run a 180...it gets the oil hot enough to burn off any condensate and other crud, you have acceptable heat for the passenger compartment, and I feel its a nice balance of the run it hotter/run it cooler arguement...but that's just me. Hope this helps!!

In addition to the reasons ceedawg mentioned, you need a thermostat to restrict flow. Without the thermostat installed, coolant can be allowed to circulate through the cooling system too fast to remove heat head from the block, and for the radiator to remove heat from the coolant. By removing the thermostat, you could actually exacerbate your overheating issue, not correct it.

Although, like you said, I suppose it's free to try in a last ditch effort to figure out the problem. Bottom line, unlike some other vehicles, DSM's need thermostats to operate normally.

 

[EvilGST]

In addition to the reasons ceedawg mentioned, you need a thermostat to restrict flow. Without the thermostat installed, coolant can be allowed to circulate through the cooling system too fast to remove heat head from the block, and for the radiator to remove heat from the coolant. By removing the thermostat, you could actually exacerbate your overheating issue, not correct it.

Although, like you said, I suppose it's free to try in a last ditch effort to figure out the problem. Bottom line, unlike some other vehicles, DSM's need thermostats to operate normally.

This is so commonly overlooked I'm glad you mentioned it.

 

[MoarAWD]

Also, just a heads up for fan shrouds:

If the shroud is on the outlet side of the fan, facing away from the radiator, it does nothing for the flow coming through the radiator. It only creates laminar flow downstream of the fan.

A very well-designed fan shroud that will create laminar flow at the fan inlet will use 5-degree polynomial (6 equations, 6 initial conditions) nozzle designs at the fan inlet and constant-area shroud on the outlet.

I mention this because there are A LOT of really bad fan setups that claim better airflow, but end up being no better (or even worse) than the OEM.

 

[motomattx]

In addition to the reasons ceedawg mentioned, you need a thermostat to restrict flow. Without the thermostat installed, coolant can be allowed to circulate through the cooling system too fast to remove heat head from the block, and for the radiator to remove heat from the coolant. By removing the thermostat, you could actually exacerbate your overheating issue, not correct it.

Although, like you said, I suppose it's free to try in a last ditch effort to figure out the problem. Bottom line, unlike some other vehicles, DSM's need thermostats to operate normally.

I havent ran a thermostat in four of the Dsm's that I've owned and I have never had any problems with any of them cooling wise including the 1000hp car that I street drive, so I wouldnt say that you by say that by any means you NEED a thermostat in these cars anymore than you need one in any other car, they warm up a little slower (in the winter) which is fine by me, other than that no big difference, I leave them out personally because its one less thing to have fail and leave me stranded or worse, I have seen many a failed thermostat in my time as a tech and more than a few warped heads or worse from it, the moving through the cooling system too fast theory was shot down by either a radiator manufacturer or a water pump manufacturer on their faq page, I will see if I can find it, in essence they said the radiator was nothing more than a big heat sink and that the coolant was in constant contact with it and the flow speed does nothing. Here this might not be the original one that I found back in the day but its the same concept from another manufacturer : http://stewartcomponents.com/index.php?route=information/information&information_id=11

Another decent thread on the subject: http://speedtalk.com/forum/viewtopic.php?f=1&t=31811

 

[ceedawg]

90 degrees yesterday in NYC. in rush hour stop and go traffic,temperature fluctuated 192 to 203 degrees. This car used to run into the 220's before not anymore. Shes doing well since I did the mods to the front bumper,undertray and ducting. Oh I have my thermostat as well. Car warms up faster ,no waste of fuel nor time for the condensation in the motor to hang around. No fear of thermostat going bad in my case. Out of ALL the cars I have had 3 DSMs,AMG C55,2 BMW M3s all have had thermostats and no overheating issues. Warped heads never a concern. German cars run hot as well.

 

[enriquez2000]

Its been about 60 in the morning and im 164 to 180 in stop and go. 85 on way home and i hovered 210 to 216 after making ac fan kick on with slim fan.. todays gonna be a scorcher so hopefully i stay below 220. Im 90percent i just need to redo fans. The ac fan dowsnt sit flush on the koyo like it did stock so im losing cooling pull