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View Full Version : Low. temp thermostats and boost...are there advantages?



Redlyne_mr2
09-06-2004, 11:11 AM
Just wondering if any of the turbo guys are running low temp. thermos. in their cars? Is it a worthwhile mod? Any adverse side effects? I can only assume that this will help lower cylinder head temps which will help to reduce detonation.

ramminghard
09-06-2004, 11:23 AM
Give it a try. Should be a fairly cheap mod.

Owned 2
09-06-2004, 02:01 PM
won't do shit.:)

finboy
09-06-2004, 03:10 PM
i'm using a lower thermostat in my car, here is a quote from a turbo dodge related page...


The 180F thermostat alone is good for 1-2 tenths in the quarter mile but the real trick is a 1/16 hole drilled in the top of the thermostat. It prevents or lessens the "thermal shock" the engine sees when the thermostat opens for the first time and "shocks" the head and block with ice cold coolant from the radiator. 1/16 is about the perfect size, 1/8 is to large and causes the engine to run cooler then 180 degrees believe it or not. Now some of you may think that "Wow 180 is good 160 MUST be better!", this isn't so- as a matter of fact rings like to be HOT and cylinder heads like to be COOL. The best temps for rings is 180F+ with temperatures below that radically increasing ring wear. All the newest engines use reverse flow cooling where the head/s are cooled first and then the coolant runs down the bores, exactly opposite of what happens to our 2.2 engines. All the newest engines also come with 2 stage thermostats to lessen thermal shock and the imports have been using "jiggle pin" thermostats for years which pretty much does the same thing as our modified unit above does...

give it a try if you want :dunno:

Alpine Autowerks
09-12-2004, 07:45 AM
an old school mod to cover problems in cooling system design or tuning.

the lower temp gives you some reserve cooling capacity,on a modern engine heat=HP. check water temps the NASCAR (the only televised racing you can see the gauges)


they are running 220-240 F

Owned 2
09-12-2004, 06:29 PM
Originally posted by Alpine Autowerks
an old school mod to cover problems in cooling system design or tuning.

the lower temp gives you some reserve cooling capacity,on a modern engine heat=HP. check water temps the NASCAR (the only televised racing you can see the gauges)


they are running 220-240 F

hahaha. My RX7 used to run that hot daily.

tsi_neal
09-12-2004, 07:27 PM
Heat doesnt = Hp at all... its the other way around

the reason that Nascrap is running such high temps is that the motors are making hella power (dont really know the exact numbers but isnt it over 600?) motors are more efficient at making heat than enything else (not an exact # but i believe the most efficient internal cumbustion engines arent quite 40% efficient) And since they get rebuilt after every race those temps dont matter much.

On a street driven turbo car you have a few things to think about that just dont matter in race motors A) A hot cylinder head will cause detonation without good enough gas. dont know what fuel nascar runs but it sure isnt 91pump B) reliability, heat kills motors fast parts will wear warp and crack when run too hot. C) oil will breakdown when run to hot, and since not everyone considers mobil 1 the cheapest oil they will use... D) related to point A many cars will adjust the timing curve based on the motors temperature so running cooler can gain some power that way (related because of octane requirements of both timing and potential detonation)

The bottom line is you CANT hurt anything by going with a low temp t-stat, might not increase power but for the 5 bucks why not.

Oh and i totally agree that going to a colder t-stat to mask cooling problems is a bad thing.


Originally posted by Owned 2


hahaha. My RX7 used to run that hot daily.

seriously, arent those things extremely sensitive to being overheated?

Owned 2
09-12-2004, 07:50 PM
generally speaking the more power you make the more heat being generated tends to go up. There are a few ways to make more power without making more heat though. I know that with rotary engines that would be to carefully port the engine, therefor shifting the power curve to the right.



Originally posted by tsi_neal


seriously, arent those things extremely sensitive to being overheated?

meh... a part of the front iron was missing (went on vacation) and the coolant seals were inpretty bad shape (equivalent to head gasket failure) so it overheated quite regularly.