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I've never seen a build with a 160 stat actually run at 160. I think it will run hotter than that forever. But my stuff with 160s cools quicker.
I'd say 150F and higher IATs most tuners will be reducing timing. 175F definitely have a bunch of timing out of it. 113 would not bother me.
Your glowing tube video made me decide to wrap mine when done.
I think once you check your tables, fan should not run unless it's just that hot. I've seen sometimes some setup get hot and stay out but there were a lot of factors... unwrapped stuff, underhood temps were insane, pusher fans not puller... Nowhere for the heat to go.
It's a 31mm freeze plug. I tapped mine in with some hi-tac permatex sealer in an LS7 water pump. It defiantly made a difference with my small radiator setup in the RX7. Some say to drill an 1/8th inch hole in it. I didn't.
This may also work. I was playing with a junk thermo and took it apart completely. It still blocks the bypass port and warms up quick. Cooling ok in my mustang anyway. shouldn't really need any wizardry. Good low temp thermo with a nice radiator and fan setup. This stuff will only help marginally in my experience.
Does it matter if the Heater ports are plugged? Mine I tapped and put plugs in. So you just tap in a 31mm freeze plug and thats all? it fits good? then delete the Tstat? How much cooler do you think it would run?
I posted on HPTuners forum asking about the elusive fan settings to actually make the MPH threshold shut the fan off. I have been disabling it with the scanner once I get going at speed which is super annoying. Hopefully someone over there knows and will bother to post the answer to the fan settings
And yes John, I can confrim that with my own experience that whatever temp value the T stat is; it seems to be a good 20* hotter that it actually runs. Yesterday after putting in the 160*F Tstat, I went for a 30 mile trip down the highway and saw temps that were USUALLY 178*F for most of the drive, occasionally went up to 185*F....... I have a blanket on the turbo, the manifolds are wrapped also. I had the crossover pipe wrapped until recently. Can't see a difference either way with that one.
Ambient temp was 88*F
In terms of IAT I only way 18*F higher IAT MAX than ambient on my drive yesterday. Currently running with no hood or inner fenders.
Forcefed: I recognize that HF red pick!
I'm also curious about the heater ports... Can you still run a heater with the freeze plug in place of a T-stat???? I'm going to probably end up knocking a freeze plug in there and quit dicking around with Tstats...... I'd like to see about 170-180*F max ECT and I think a freeze plug may be the only way to get me there, especially once it continues to get hotter here in OK, I put the hood back on, and I equip A/C.
I know we have talked about drilling holes in Tstats coming from the SBC days. However, It makes me wonder if drilling a few holes in a 160*F LS Tstat could give operating temps that were closer to 160*F, instead of 20* higher. The little flappy nipple thing I was talking about above I removed like every other thermostat I've put my hands to so far. Seems like it's a factory bleed hole anyways and that little nipple thing can seal it up in some situations.
I'm content with the operating temperatures I'm seeing with the 160*F Tstat, but still intend to experiment with getting them lower, either through drilling holes in the 160*F Tstat or just going the freeze plug route that works well for some guys like rotary and forcefed.
I have three 1/8 or 3/16” holes in my 160 and no real change in temps. Don’t think they flow enough to make a big enough change. In my pic you can see the 160 on the left, it had 1 hole and I’ve added 2 more including the flap.
Sometimes i I see a high 165-169*F on the highway in cool
weather but not really during the summer. Usually
i the 180s.
Unless you run a race/hobby car you don’t really want to plug the T-stat port. temps in the high 170s low 180s are ideal before a high boost pull IMO. Don’t really want much lower. You want the oil temp up quick. You collect a lot of moisture in the crank case cruising at low temps and warming up slowly. When street cruising I leave my fan off till I hit 210* or so then cool it down.
I can’t say what difference it will make for anyone else’s setup. When it wasn’t super-hot out I was fine. But I’d creep to 220-225 on 100*+ days in traffic. With the LS1 pump, 160 thermo, and taurus fan on high. I switched to the LS7 water pump. (No idea if this pumps more volume. Rumor is it does, but I can’t find any data. It is like 2lbs lighter weight.) Then plugged the thermo port and rarely go over 200 now in 100*+ heat. Usually in the 178-185 range on normal temp. days and night cruising with the fan on low. I run a small 14x14x3.5” triple pass 3-row core. (fork lift radiator) Probably the nicest small core radiator I’ve seen, but It’s far from a properly sized “race” radiator.
Heater will still work fine with the bypass plug in. If you aren’t running a heater then you want those plugged. Looping them as many do has a similar effect to not running a thermo. It allows fluid to bypass the radiator through those parts. They are smaller though... so it’s not likely to cause an overheat situation. But if they are looped coolant is bypassing and the system is not cooling as well as it could. I get tapping and plugging can be a pain, so just stuff something into the “loop” to block flow and press on. I used a big wire nut last time.
Interesting. I think I'm headed down the path of putting a freeze plug in the bypass hole of the water pump before too much longer but we'll see.
As far as me wondering if the fan could be shut off at a MPH threshold in HPTuners instead of ONLY a ECT threshold. It looks like the answer is NO. Super disappointing. It sure would be nice if you could set the temps at what you want to run the thing as cool as possible around town and ALSO a MPH threshold to shut the fan off regardless of temp as soon as you're going X MPH.....
Someone on the HPT forum has said that they are using the 411 PCM and are getting the MPH shutoff to work. I have asked them to share the secret lol....
Another thought I had was to use a 7427 PCM from a stone age TBI truck as a standalone E fan controller. I have a box of em, and I can DEFINITELY get one to run a fan like I want easily.
When I'm cruising down the highway I see temps ranging from 178*F to 185*F with the 160*F Tstat in there.
What kind of coolant temp increase are you guys seeing when you make a hit and build up some boost???
No real input here but the mph shutoff works on the 411 ecu on my brothers s10 that we put together. However, I have had issues getting the electric fan controls working correctly without a bunch of quirks on other 411 ecu's. It seems hit or miss randomly for me.
I drove the truck through the Oklahoma summer and everything was just fine. Not losing any coolant, and no combustion gases detected with a CO detector in the coolant either. Super cool idea from rotary1307cc thanks for that man.
My fan setup is right on the edge of being unacceptable..... I have seen coolant go as high as 217*F while idling in traffic on a 100*F day..... Get going down the highway and temp drops and stabilizes around 178*F......
This was a huge learning experience for me and one thing I learned is that a cooling system that works in a N/A setup might not with a turbocharger factored into the equation. My 1 fan keeps me from overheating but it does get fairly warm idling on a hot day like I posted above.
1 fan that only covers 65% of the radiator and has to pull air through a FMIC and A/C condenser BEFORE it even hits the radiator.... Yeah my fan setup on my next turbo build will be OVERKILL....... Everything is working fine on this one though.
Just read entire thread as I’m trying to get temps down as well. From what I read and understand, if you run no thermostat, you need to block bypass ports in the pump? Or run it as is with a thermostat?
The one thing I learned from this is that the LSx tends to run a tad on the warm side at least from the factory. My stock 2004 GMC with a 5.3 is usually around 210*F most of the time. Idling in traffic with the AC on I've seen it go to 235*F or so. I wouldn't worry about that. With a turbo I'd like to keep it cooler however.
Yeah you need to block the bypass in the pump if you ditch the Tstat.
Something else to keep in mind is that if you can't get the temp up hot enough for a while you won't ever burn off the water in the oil. Hot is good, to a point.
Pretty sure running over 200 is strictly for emissions. No reason you’d want to run it hot I’m aware of in a forced induction setup.
Finally my mustang sits at 180-190 even on 100* days. Standard griffin universal radiator, surge tank, 160 thermo, Taurus fan.
Only change I made was a radiator cap. I found I was getting air caught in the lines due to the radiator cap on the RAD not being free flowing into the surge tank. I'd see really odd temps and even overheat some days... and not on others. Id bleed/burp the system and it would work good for a week. Then let the car sit a week and it would overheat. It made no sense to me. Installed a pressure relief style cap and propped the relief open. Now the cap on the surge tank regulates it all and the system doesn’t get air trapped anymore. Been working great all summer anyway. Need to do the same on the “race car” .
Pretty sure running over 200 is strictly for emissions. No reason you’d want to run it hot I’m aware of in a forced induction setup.
Agreed. If I am running around town on a hot day in the turbo truck the fan stays on most of the time. Hit the highway and it goes off as the temp stays right around 178*F..... If I'm idling at a stop on a hot day the 1 fan I have SLOWLY brings the temp down to the point the fan shuts off for a couple minutes or so then it comes back on again till it can drop the temp.
My fan setup is less than ideal with 65% coverage and having to pull air through FMIC, AC Condenser and then a radiator but since it does keep it cool (enough) I'm just going to leave it be. I'd add another fan next to the one I have but I piped my IC piping right in the damn way........ Oh the things you learn on piecing together your first JY turbo LSx build.
One thing that never dawned on me until i talked to griffin radiators was how much strain the auto trans puts on the coolant system. So when they built my radiator i didnt have them incorporate bungs into it for the trans. This is on a twin turbo lq4 with 2 intercoolers.
They told me to run an auxillary cooler with a fan which does very well on hot hot humid days in wisconsin.
Since i went that far i got an oil cooler as well. Both dont have a ton of airflow but they do keep the temps down it appears.
my buddy installed an oil cooler on his 572 and it did absolutely nothing to his overall coolant temperature. His issues are from air damming in his engine bay and from his electric fan setup not flowing enough.(cheaper aluminum radiator that is bigger than mine and a universal flex a lite setup). So he switched to a mechanical fan.
Every situation is different. Ive had luck by adding water wetter to 50/50 coolant on mud trucks no bs. It seems as though its a definite trial and error situation to keep the temps down for each application.
Last edited by 1985cucv; Sep 28, 2018 at 01:33 PM.
Reason: Wrong word
The one thing I learned from this is that the LSx tends to run a tad on the warm side at least from the factory. My stock 2004 GMC with a 5.3 is usually around 210*F most of the time. Idling in traffic with the AC on I've seen it go to 235*F or so. I wouldn't worry about that. With a turbo I'd like to keep it cooler however.
Yeah you need to block the bypass in the pump if you ditch the Tstat.
Something else to keep in mind is that if you can't get the temp up hot enough for a while you won't ever burn off the water in the oil. Hot is good, to a point.
looks like I’ll be putting the 160 thermostat in tomorrow morning
2004 gto here. stock fans, thermostat (i assume, I never changed it) stock radiator, no coolant additives, just coolant and water. No added fans. FMIC, but its only 1/3 the height of my radiator and condenser. I did add a cheapie trans cooler. My coolant temps are 178-181 on a hot day. I do not have my hot side exhaust run around the front of the engine, its around the back under it and the trans. I have a blanket on the exhaust housing. My down pipe and my wastegate exit pipe are wrapped. My manifold is not. My under hood temps do need seem to be any hotter than normal. My hood does not get hot. I draw cool air from outside the engine bay into the turbo. All of the things i did when i built the turbo setup was considering heat and imagining how the oem's would do it. I wemt through great troubles to keep hot things away from things that dont like to be hot. I dont have an ideal size intercooler compared to what conventional thinking would be, but most people through a small filter on the turbo and suck in 200f+ temp air from under the hood which requires a huge intercooler to cool it off......a huge intercooler that helps to flow hot air onto your condenser and radiator. Think about that for a minute.............
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