JaimeVrod

Is there any performance benefit to be gained by using a cooler T-stat?

I'm switching to a smaller blower drive pulley and getting a retune, would it make sense to have a cooler stat installed?

If yes, I'll be doing the T-stat installation myself. Is there anything I need to be aware of like how to burp air out of the cooling system or similar?

Pitufina

It'll run cooler while on the highway, but once stopped the temps will go up to where the ECM commands the fan to come up by percentage. Tuners don't like to change the ECM fan commands because the draw required to run the fan for longer periods ends up melting the connector right at the module thing by the fan motor.

schpenxel

What's in there now?

What are you wanting to go to?

What temps are you seeing?

I have a 165* (comes with ECS kit) and I'm cruising in the 190's usually. It was 85* outside today and I was right at 200*F

JaimeVrod

I have the stock t-stat which I'm not sure what temp it opens at, but when I cruise, my coolant temp is normally 202-204F independent of ambient temperature. When I stage at the drag strip, I think my coolant temp has always been 196 or higher. So I'm wondering if a stat with a lower opening temperature would improve performance by allowing a little more timing advance.

schpenxel

Stock timing setup (at least on a 2005) doesn't pull any timing until 230*F. IAT starts pulling at 90*F though so I could see hitting that one easier

Regardless, lower temp stat isn't going to help for that without reprogramming the fans. Not sure if you have access to HP Tuners to do that or not.

It won't hurt anything. You just won't see much difference except on the interstate where there's enough airflow to bring the temps down to the lower limit that the thermostat allows, at least IMO

JaimeVrod

Schpenxel,
That was actually very helpful. Sounds like a t-stat change isn't worth the effort.

I've noticed a big increase in ET when I'm hot lapping at the drag strip and the intercooler gets heat soaked. What are my options to reduce IAT besides N2O or water/meth injection?

I was actually thinking about hitting the outside of the intercooler with isopropyl alcohol from a spray bottle before a run down the strip. The evaporation should really cool down the intercooler.

schpenxel

Eh, can't help there. Sorry, somehow I missed the fact that you're supercharged.

I've heard of people spraying the intercooler with N2O but I dunno.

Are you running meth at all right now? It's great about lowering IAT's

Streetk14

Personally, I'd say it's worth changing the thing. The stock t-stat is rated somewhere between 192-195 degrees from what I remember. How much of an effect it has really depends on your cooling system efficiency and fan settings.

I have a DeWitts radiator, 160 t-stat and extended fan tables, so I have a pretty decent control over the system. My stock fan is probably the limiting factor for me -- but I live in a mild coastal climate, so no stop & go 100 degree days for me. At that point, a lower t-stat likely won't help at all. My temps are usually controlled below 190, so I feel there is a benefit for me. Both my stock C6s have run right around 200 at a steady freeway cruise in cool weather.

And while the stock calibration might not pull any timing until 230 or so, there is likely a benefit to cooler cylinder head temps when asking for max power.

Some here might be sick of me talking about German car technology, but the strategy BMW uses on it's very well controlled cooling systems (electric water pump, PCM-controlled thermostat, electric fan) is pretty telling. They run the coolant between 200 and 210 during "normal" driving. When you go full-throttle, the electronically controlled t-stat opens, the water pump speed increases, and the temps are dropped into the 180's-low 190's. I feel this is to allow more timing/less knock and better performance.

Since our LS motors can't do this, I try to keep mine in that "performance" zone. As long as the oil temps warm up, it isn't hurting anything (other than maybe emissions or efficiency slightly). With engines that are usually pretty octane limited, I think there is an advantage to running cooler if you can.

neverstop

meth kits are a no brainer for supercharged cars imo. one of the best things to do and not expensive.

JaimeVrod

I'm not currently running meth. I asked my tuner about installing meth and he said they wouldn't do a special tune for it because if the computer is tuned for the methanol and the pump fails, the engine could blow from detonation. At first I thought they wouldn't install a meth injection kit but I was wrong. They will install it for cooling/protection but they seemed to think the meth injection would reduce the quantity of air/gasoline being inducted and thereby have negligible power increase, perhaps even hurt power a bit.

I'm willing to try the meth injection but if no special tune is going to be applied, then I'd prefer to do the installation myself. Which meth injection kit is the easiest to install and makes use of the windshield washer reservoir as the methanol tank?

How do I monitor IAT?
Is Dash Logic module required?

neverstop

on real extreme applications (1k hp+) that may be true but you can just adjust the tune so that if the meth setup fails, then the IATs will spike, and the computer can pull all the timing out of the motor to save it. So I would find a better shop if it were me because what they are telling you isn't true imo

meth has basically no drawbacks on a pump gas setup though best I can tell, you'll make more power, the car will be more reliable, the motor will last longer and it's not expensive.

5 Liter Eater

Anyone ever try removing the tstat alltogether?

JaimeVrod

Removing the tstat should reduce coolant temp, but might have to reprogram the fan turn on temp. Also, it might cause some other unexpected problems. On my 89 mustang gt, i believe removing the thermostat would force the computer to stay in a closed loop mode and that could reduce power.

5 Liter Eater

I've already bypassed the PCM for cooling. I have a relay that turns the fans on when the engine is running. Fans full blast helps quite a bit.

Suds

I did that on a big cammed motor, it ran rough without the thermostat until the motor and radiator warmed up above 120-130F.

LemansbluebyU

Leave the stock thermostat in there, your not going to see any benefits to changing it out especially where you live. These motors are designed to be run at certain operating temp's. Just because we as humans think 200 degrees is hot, the metals inside the motor expand and contract obviously and at those temps the motors are very happy. You are better off getting yourself a better radiator with higher capacity to help maintain those temps, fan control for slower speed operation and most definately meth injection on a boosted motor for lowering IAT's HOWEVER, if you decide to run meth your motor/tune will become dependant on it for proper performance......Yes you can tune in some safety factors but ultimatly it is on you to make sure you have enough meth in the car when your out driving!! Your shop doesn't like to tune for it because most people are lazy and won't keep an eye on it, then if something goes wrong, like most people do they don't want to take the blame themselves for making a mistake and forgetting to fill the meth tank, must have been the tuner so they go back after the shop for their 10k+ motor rebuild after a meth melt down. That is why they don't want to tune meth, not that they can't, there is just a greater responsibility on the customer to run it correctly and things can get ugly if you don't fully understand how to use it and are willing to accept the concequences if something goes wrong. Other than that it is a proven, wonderful compliment to any boosted motor!!!

x r8ted

I think LemansbluebyU hit it right on the head. I run 100% meth and there are zero draw backs. Its just not for the lazy driver like said before.

JaimeVrod

LemansBlueByU and X R8ted,
What meth system are you using, where is the pump located, are there any special sensors required and are you using the WW tank or a separate tank.

I read a thread about one system where the pump is mounted inside the front fender and the mfr recommends rebuilding the pump every year. I don't want a system where regular maintenance requires removing a body panel.

x r8ted

Mine it tapped into the windshield washer fluid tank. My pump is located in my drivers side fender well. I am using the snow stage 2 kit, which I don't recommend if you running 100% meth. I will soon be changing it out for a Alky Control system. Its just flat out the best imo when your talking about meth systems.

LemansbluebyU

Alky control is the best, I just ordered a dual nozzle system.....I have done ALOT of reading and research about this before making my decision, there isn't much of a down side considering the gains you get BUT yes there are maintenance issues hence what I mentioned before lazy or uninformed people.....this is not a completely set it and forget it item, once tuned if you make no other changes you shouldn't need to do anything except for make sure your tank is full or at least not running out. Yes you need to maintain the pump depending on how you use the system. Most people mount the pump out of sight but that may mean you need to remove something to access it or you can mount it somewhere you can get to it, that's up to you and how you like things to be in your car. Ultimately when using meth it is up to you to learn about it and how to use and maintain your system, if you don't take the time then chances are you will be someone who has trouble with it, it's not for everyone!