Calling all turbo daily drivers
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Calling all turbo daily drivers What are you guys doing to keep your turbocharged dailys running cool in the hotter months.
I have a fullsize GMT400 with one of the bigger radiators and a summit branded electric fan. Now that's it's warmed up it's running hotter than I'd like. Not overheating but I need to get it in check.
I just drove 10 miles at 70 MPH and the fan stayed on the whole time....
What should I try next????
Stock thermostat is in currently. Maybe swap to a cooler one???
Now that I have an intercooler in front of the radiator I wonder if that is choking off the air flow to the radiator... The IC is BIG....
Also just noticed that my radiator cap is puking just now.... Maybe that's the source of my problems??
I also thought about a cowl hood. Would that help??
I have a fullsize GMT400 with one of the bigger radiators and a summit branded electric fan. Now that's it's warmed up it's running hotter than I'd like. Not overheating but I need to get it in check.
I just drove 10 miles at 70 MPH and the fan stayed on the whole time....
What should I try next????
Stock thermostat is in currently. Maybe swap to a cooler one???
Now that I have an intercooler in front of the radiator I wonder if that is choking off the air flow to the radiator... The IC is BIG....
Also just noticed that my radiator cap is puking just now.... Maybe that's the source of my problems??
I also thought about a cowl hood. Would that help??
Can be as simple as a bad rad cap. Don't underestimate fans. You either needs stock fans or the derale 16925 or equivalent and move at least 3500cfms to keep a turbo engine cool during the summer with ac. Assume you still have the air dam installed? Should be running a 180 or 160 stat.
I use a stock truck thermostat, a 195* one. It pretty much stays around that temperature unless I am hot lapping it at the track or doing multiple tire vaporization tests in a row.
Cheapest aluminum ebay double pass I could find.
My fan is set to come on at 210* and turn off at 190*
It'll puke into the overflow a little when I turn it off, as the heat from the heads transfers to the coolant, the coolant expands and builds pressure. It draws coolant back in as the motor cools.
Just make sure you don't have a bubble and remember it's not a SBC that you have to run at 160*
Cheapest aluminum ebay double pass I could find.
My fan is set to come on at 210* and turn off at 190*
It'll puke into the overflow a little when I turn it off, as the heat from the heads transfers to the coolant, the coolant expands and builds pressure. It draws coolant back in as the motor cools.
Just make sure you don't have a bubble and remember it's not a SBC that you have to run at 160*
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What is controlling your fans? Is it set to bring them on at the proper temp? What temp is the truck running at? What is your timing under cruising conditions? And as stated, airflow is paramount. Although it's likely driving over 35 or so wouldn't require a fan at all on that style of front end.
Stop and go traffic you need as many big, high quality fans as you can fit. Ebay fans are SH$T, get good ones. But like apache said 70 on the freeway you shouldnt need it. I know my tahoe p01 ecm was setup to disable the fans at 50mph. The other tunes ive seen than had efans were similar.
Also something simple, make sure the fan is blowing the correct way. It should be moving air towards the engine, seen that 1 before lol
Also something simple, make sure the fan is blowing the correct way. It should be moving air towards the engine, seen that 1 before lol
Make sure it's burped properly, ls engines can be a total pain in the *** to fill with coolant.
Taurus fans work great and can be had on the cheap. Might try water wetter too, stuff actually works as advertised.
Taurus fans work great and can be had on the cheap. Might try water wetter too, stuff actually works as advertised.
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Thanks guys. Much appreciated. I will start with the simple obvious thing and get a new radiator cap on it first.
Here is how I have been filling the cooling system:
First raise the front of the truck to encourage air bubbles to purge out.
Second pour coolant straight into the upper radiator hose so you are pouring coolant directly into the engine.
Then I fill the radiator, start it and let it run to operating temp. Shut it off and let it cool down and top it off. Rinse and repeat this step.
Also, I find that sometimes taking the steam tube hose off and leaving it off until coolant dribbles out of it helps.
I have the PCM controllilng the fan, I don't have my laptop in front of me at the moment so I will check later tonight what the commanded temps are that I have them set at, I can't remember.
I need to look into the timing for those load cells also, not sure.
Yep, driving over 35 the fan is staying on which tells me it's either not enough airflow OR the leaking radiator cap.....
I think the fan I have on is Flex-A-Lite Syclone S-Blade Electric Fans 398.... 2500 CFM.
I hope I didn't build a winter only daily driver lol.... So the consensus is that you CAN keep one of these turbo engines cooled in the warmer months???? I had no idea how much underhood heat one of these ******* makes. Now I know!!
Here is how I have been filling the cooling system:
First raise the front of the truck to encourage air bubbles to purge out.
Second pour coolant straight into the upper radiator hose so you are pouring coolant directly into the engine.
Then I fill the radiator, start it and let it run to operating temp. Shut it off and let it cool down and top it off. Rinse and repeat this step.
Also, I find that sometimes taking the steam tube hose off and leaving it off until coolant dribbles out of it helps.
I have the PCM controllilng the fan, I don't have my laptop in front of me at the moment so I will check later tonight what the commanded temps are that I have them set at, I can't remember.
I need to look into the timing for those load cells also, not sure.
Yep, driving over 35 the fan is staying on which tells me it's either not enough airflow OR the leaking radiator cap.....
I think the fan I have on is Flex-A-Lite Syclone S-Blade Electric Fans 398.... 2500 CFM.
I hope I didn't build a winter only daily driver lol.... So the consensus is that you CAN keep one of these turbo engines cooled in the warmer months???? I had no idea how much underhood heat one of these ******* makes. Now I know!!
Last edited by ElQueFør; Apr 16, 2018 at 08:51 PM.
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Thanks guys. Much appreciated. I will start with the simple obvious thing and get a new radiator cap on it first.
Here is how I have been filling the cooling system:
First raise the front of the truck to encourage air bubbles to purge out.
Second pour coolant straight into the upper radiator hose so you are pouring coolant directly into the engine.
Then I fill the radiator, start it and let it run to operating temp. Shut it off and let it cool down and top it off. Rinse and repeat this step.
Also, I find that sometimes taking the steam tube hose off and leaving it off until coolant dribbles out of it helps.
I have the PCM controllilng the fan, I don't have my laptop in front of me at the moment so I will check later tonight what the commanded temps are that I have them set at, I can't remember.
I need to look into the timing for those load cells also, not sure.
Yep, driving over 35 the fan is staying on which tells me it's either not enough airflow OR the leaking radiator cap.....
I think the fan I have on is Flex-A-Lite Syclone S-Blade Electric Fans 398.... 2500 CFM.
I hope I didn't build a winter only daily driver lol.... So the consensus is that you CAN keep one of these turbo engines cooled in the warmer months???? I had no idea how much underhood heat one of these ******* makes. Now I know!!
Here is how I have been filling the cooling system:
First raise the front of the truck to encourage air bubbles to purge out.
Second pour coolant straight into the upper radiator hose so you are pouring coolant directly into the engine.
Then I fill the radiator, start it and let it run to operating temp. Shut it off and let it cool down and top it off. Rinse and repeat this step.
Also, I find that sometimes taking the steam tube hose off and leaving it off until coolant dribbles out of it helps.
I have the PCM controllilng the fan, I don't have my laptop in front of me at the moment so I will check later tonight what the commanded temps are that I have them set at, I can't remember.
I need to look into the timing for those load cells also, not sure.
Yep, driving over 35 the fan is staying on which tells me it's either not enough airflow OR the leaking radiator cap.....
I think the fan I have on is Flex-A-Lite Syclone S-Blade Electric Fans 398.... 2500 CFM.
I hope I didn't build a winter only daily driver lol.... So the consensus is that you CAN keep one of these turbo engines cooled in the warmer months???? I had no idea how much underhood heat one of these ******* makes. Now I know!!
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From: Florida
when you open the hood does it feel like an oven?
i had a single turbo s10 and it was like that. i had to take it all apart and wrap everything with that lava stuff and that helped reduce under hood temps a lot which also improved engine cooling in general.
i had a single turbo s10 and it was like that. i had to take it all apart and wrap everything with that lava stuff and that helped reduce under hood temps a lot which also improved engine cooling in general.
When I put a new motor in or have the heads off I fill the motor from the steam tube itself. Never have any problems when doing it that way, upper radiator hose has left me with bubbles before but has also worked too.
Hood cut outs also work great for getting heat out of the bay. Looks ricer but my car is japanese so it fits.
Hood cut outs also work great for getting heat out of the bay. Looks ricer but my car is japanese so it fits.
The fans should be shutting off over 35mph or whatever the tune is set to. If they stay on at speed it becomes more of a restriction to air flow then it helps. Try adjusting the tune to shut the fans off at speed.
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Good point about hot being relatively subjective! I know the LS engines tend to run hotter in general than the old SBCs. I see temps around 187*F to 190*F going down the road.
I feel kinda dumb but I think there is why the fans are staying on.... I never changed them from the stock LS1 411 PCM values and there is a truck thermostat in there which is 187*F..... So no wonder the fan isn't shutting off.... Granted this wasn't happening a month or two ago when it was colder!
I have 3 choices under the fan tab in HPT.... 2 fans, Aux fans, No fans..... I currently have it on 2 fans.... Is this the correct setting even though I just have the one large flex a lite fan I mentioned???
The disable speed for fans under (First Stage) is set to 35 MPH..... So I wonder why that's not cutting it off????
It doesn't feel like an oven when opening the hood. Not yet at least. Maybe once it warms up some more in a couple months though lol. I have heat wrap on the manifolds, and the crossover pipe. Also running a turbo blanket.
Damn, filling through the steam tube? That must take a long time.
Also, I have a question for you guys about IATs....
Today Ambient was 83*F... Made a short run logging some data and saw IAT right around 100*F as long as I'm moving.... Pretty much the same IAT whether in boost or not. If I stop and idle IAT will rise to 113*F.... Heatsoak from sitting still I suppose.
At what temp does a hot IAT become a problem? I've read that around 20 degrees above ambient is acceptable for a intercooled NON-E85 setup WITHOUT methanol.... Is this correct?
I feel kinda dumb but I think there is why the fans are staying on.... I never changed them from the stock LS1 411 PCM values and there is a truck thermostat in there which is 187*F..... So no wonder the fan isn't shutting off.... Granted this wasn't happening a month or two ago when it was colder!
I have 3 choices under the fan tab in HPT.... 2 fans, Aux fans, No fans..... I currently have it on 2 fans.... Is this the correct setting even though I just have the one large flex a lite fan I mentioned???
The disable speed for fans under (First Stage) is set to 35 MPH..... So I wonder why that's not cutting it off????
It doesn't feel like an oven when opening the hood. Not yet at least. Maybe once it warms up some more in a couple months though lol. I have heat wrap on the manifolds, and the crossover pipe. Also running a turbo blanket.
Damn, filling through the steam tube? That must take a long time.
Also, I have a question for you guys about IATs....
Today Ambient was 83*F... Made a short run logging some data and saw IAT right around 100*F as long as I'm moving.... Pretty much the same IAT whether in boost or not. If I stop and idle IAT will rise to 113*F.... Heatsoak from sitting still I suppose.
At what temp does a hot IAT become a problem? I've read that around 20 degrees above ambient is acceptable for a intercooled NON-E85 setup WITHOUT methanol.... Is this correct?
Last edited by ElQueFør; Apr 17, 2018 at 09:13 PM.
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New radiator cap seems to have fixed the coolant puking at the radiator neck.
A tiny little bit seems to still drip out, I'm going to check over the fill neck real good because with the smaller radiator that was in here a few days ago it wasn't doing this.
In some searching I have read about lifted heads etc. I find it unlikely in my case since I have LS9 gaskets, ARP bolts, 8 PSI boost MAX, and a pretty conservative timing table. Max timing in boost is about 13* IIRC? Rarely do I see any hits in the Spark Retard Histogram. But when I do it's not even enough to fill the cell with a full count of "1", just slightly red right there. And I think it's false knock anyways. ChopperDoc (Ron) taught me that usually real knock appears in kind of a stair stepped fashion on the Histogram.
Anyways.... I'm running a stock 92 Chevy truck radiator cap. I wonder if this is correct for the LQ4 that's in there?
Also, will you guys please weigh in on my statements/questions about IATs and the "correct" fan settings above?
A tiny little bit seems to still drip out, I'm going to check over the fill neck real good because with the smaller radiator that was in here a few days ago it wasn't doing this.
In some searching I have read about lifted heads etc. I find it unlikely in my case since I have LS9 gaskets, ARP bolts, 8 PSI boost MAX, and a pretty conservative timing table. Max timing in boost is about 13* IIRC? Rarely do I see any hits in the Spark Retard Histogram. But when I do it's not even enough to fill the cell with a full count of "1", just slightly red right there. And I think it's false knock anyways. ChopperDoc (Ron) taught me that usually real knock appears in kind of a stair stepped fashion on the Histogram.
Anyways.... I'm running a stock 92 Chevy truck radiator cap. I wonder if this is correct for the LQ4 that's in there?
Also, will you guys please weigh in on my statements/questions about IATs and the "correct" fan settings above?
Where is your sensor? I have mine in the intake right behind the TB and see iats similar to yours. Never been a problem just driving around. At the track with my eBay intercooler I'd see 160 after a pass on medium boost, so I started spraying water meth on it
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My IAT is in the charge pipe a few inches before the TB. What I saw yesterday is that getting into boost the IAT either stayed the same or in a few cases dropped down a degree or so.
Anyone know about the fan mystery? Thinking I need to switch the setting over to "Aux Fan"
Anyone know about the fan mystery? Thinking I need to switch the setting over to "Aux Fan"
My IAT is in the charge pipe a few inches before the TB. What I saw yesterday is that getting into boost the IAT either stayed the same or in a few cases dropped down a degree or so.
Anyone know about the fan mystery? Thinking I need to switch the setting over to "Aux Fan"
Anyone know about the fan mystery? Thinking I need to switch the setting over to "Aux Fan"
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Exhaust is wrapped. Turbo has a blanket. The dual rad is an interesting idea. A friend told me about a car he used to parade with and to make it run cooler he simply added to large holding tanks for water thereby increasing the capacity.
I always disliked cowl hoods kinda simply for the fact that most people, around here anyways were just posers putting cowl hoods on boring stock stuff lol. I suppose it might actually be warranted in my case so I'm considering it!
I have the fenderwells out to further help airflow.
No trans cooler in this one! Running my 32 spline Frankenstein T56.
Here is a rambletron video I made not too long ago, you can see the engine and underhood from 2:15 to 5:45 roughly. The radiator in this video I have since replaced with one twice as thick/deep?
I always disliked cowl hoods kinda simply for the fact that most people, around here anyways were just posers putting cowl hoods on boring stock stuff lol. I suppose it might actually be warranted in my case so I'm considering it!
I have the fenderwells out to further help airflow.
No trans cooler in this one! Running my 32 spline Frankenstein T56.
Here is a rambletron video I made not too long ago, you can see the engine and underhood from 2:15 to 5:45 roughly. The radiator in this video I have since replaced with one twice as thick/deep?