I have been bouncing this around with a friend of mine and haven't came to a conclusion about how if at all coolant temps effect power and timing #'s. I understand needing to be warm enough, but what would be expected if you could pull temps down for an average of 180-185, to 170 or so. i'm assuming this would only be worth while if you were trying to totally max out a setup.
i was thinking radiator cap, low temp thermostat and straight water... would it be worth it, or would you need a new radiator as well to get decent results?

 

There is a timing trim based on coolant temp, can't tell you the numbers of the top of my head (its in another thread)

However lowering coolant temp wont give you more power on its own.

 

Lowering the coolant temp can help with heatsoak and hotlap racing a bit but I doubt that the 10* difference is enough to show any signifigant power gains. Though, rule of thumb is roughly 1-3% power gain for every 11*F of air temp drop entering the combustion chamber. Since the engines radiant heat certainly warms up the intake manifold it may help slightly in that case. Getting a lower temp thermostat and adding some Redline Water Wetter to a 30% anti-freeze/70% water mix certainly helps quite a lot too. Mattjin has a thread with some coolant fan tables he found which would be useful in engaging the fans sooner so you aren't relying solely on the thermostat to keep the temps in a certain temperature window. I do know that engine designers rely on a certain engine temp for proper metal expansion to create the proper seals within the engine so this may have a SLIGHTLY adverse effect on their intentions but we are only talking about 10-15 degrees here so I'm not the person to confirm this or not.

It would be cool to see someone test this on a dyno, maybe Razorlab would be up for the challenge??

 

A thermostat can not possibly reduce your water temps when you're racing. It can lower your normal operating temp at idle or cruise, but all that's going to achieve is potentially worse gas mileage..it's called "normal operating" temp for a reason.

A better radiator is what you would need.

 

Straight water = bad idea. You need antifreeze. It not only decreases the freezing point but also raises the boiling point. Boiling your fluid (especially in the head) is catastrophic.

 

Increasing the pressure level of the system also raises the boiling point so upgrading to a higher pressure radiator cap helps as well. Straight water wicks away heat farrr better than anti-freeze so only use as much antifreeze as is required for your climate. Anti-freeze's #1 job is just that, to stop it from freezing. Increasing the boiling point comes second.

 

Yep, even straight DI will kill your coolant system. If you want to eliminate the antifreeze for lower temps just put in some of that alkali wetting stuff. If temps decrease too much just add a little antoifreeze to the concoction

 

it's all speculative on my part i was just wondering aside from keeping temps down for racing/hot lapping, i thought you might be able to sustain a a bit of extra timing for the all money spent, instead of just lower coolant temps