TurboZ

actaully you are wrong on two accounts. first the hole on the thermostat is set at a certain size to "control" coolant flow. in certain cases only a restrictor plate is used to cool properly. if the coolant flows to fast it will now absorb any heat so there will be no transfer and then an overheated engine. to slow and there will not be enough of an exchange of heat to cool the engine. just wanted to clear up that a bigger whole is not always better. just think of it this way.. would you want your g/f that way?

now on the other account a hotter motor does not produce more power. most cars run between 200 to 220 degrees. the reason is not power output. it is for emmisions. a quote from GM" the small block 350 claims claims no power difference between 180 and 200 degrees" the only reason for a colder or warmer thermostat is for a hotter heater during winter.. and now for emmisions. the higher demperature increases combustion temperatures which makes burns more of the fuel in the cylinder.

hope this helps clear up the air.

also glad to hear your car is not overheating... i would be really scared if i was boostin that much and saw a temp that high.

timzcat

iTrader: (10)

I guess you are responding to me on the second point. I never commented on the thermostat orrifice issue. Although a thermostat is better than a restrictor because it warms the engine faster, which is obviously better for a number of reason. Restrictors are only used in racing because obviously you don't car about all those issues in a race car.
My point was power makes heat. The same engine at 180 and 200 has the same power output. But 160 is kind of cool. Compare the same engine at 160 and 200. By that theory a cold enigine would run better, but the problem is without the heat, the fuel does not atomize well and you lose power.
Regardless this is a turbo engine and the exhaust gas expansion is important and hotter gas expands faster. Cool air in hot air out. Put a turbo car on the dyno cold and hot and see which one makes more power?

BadazzCR

iTrader: (5)

Just FYI I dyno'd my car yesturday and the cooler thermostat actually lost 10hp.

90GSX-03EVO

iTrader: (27)

I've seen a lot of types of cars that have thermostats that open around 190 to 200 from the factory and here is my conclusion. You might get away with running one that opens as low as 180 degrees, but I wouldn't go any lower than that. In support of this, I put a 160 degree thermostat in my Jeep that came with a 190 thermostat stock and it screwed the computer all up. Not learning from my mistake, I put a 160 degree thermostat in my second 1990 Eclipse GSX. I was in Puerto Rico (military) at the time of these two changes and I was tired of the heat so I thought my cars were, too. On the GSX, I was running an external wastegate and it required me to ditch my acc fan but yet I kept my AC so I knew it would be getting pretty warm in the hellish traffic jams we have here. I thought a 160 thermostat would do the trick. Talk about a mistake. It caused the car to run worse than it had since I bought the thing, and it sucked donkey *****. When I went to put a stock temperature thermostat back in it, I cracked the thermostat housing........stoopid of me. Since I could not find one on the island for ****, I had to go on dsmtrader.com and get good ole Kash Krickler to send me a replacement. The car sat for about a week with a cracked thermostat housing and I didn't even think about it. When I went to put the new thermostat housing on, there was all kinds of gunk all over the place from .......well.....I guess you could call it an oxidation of some sort. I didn't cover it up after I cracked it......this was also stoopid of me. There was sludge all in my radiator hoses and it also sucked donkey *****. I goess I didn't get it all out, because soon after, my turbo failed. Inspection showed that the water inlet line was clogged with goo and I guess it just overheated and melted the poor thing. I was playing around with a T-28 Garret turbo on it at the time, so I didn't really care, it just gave me the excuse to buy the big 16G and finally come back to the world of noticible turbo lag. Anyway, to get back on-topic.......I would stay away from the 160 degree thermostats. Some people even think that taking out the thermostat in hot environments will help the car perform. This might be a good troubleshooting tool, but the car needs that thermostat to stay closed when it first starts up in order to properly heat up the motor to normal temperature. On a car with carbs, you might be able to get away with this, but it just doesn't seem to be the way to go on a car with fuel injection. Just keep the stock thermostat and add some watter-wetter if you want......that stuff should work. I have some friends that swear by it (even though I haven't tried it yet).

Josh

jingmag

I had the same problem with my EVO IV RS. Tried everything. Thought of everything, timing, A/F mix, boost levels, etc. It turned out to be a busted thermostat valve. mine should've opened at 76.5C but didn't so the water in the engine block couldn't get to the radiator to cool. a simple test to see if your thermo is busted is to run the engine, put a water hose into your radiator and keep the water running. if your temp still goes up and the radiator is actually cool to the touch then your water isn't corculating from the block to the radiator. your thermo is'nt opening at the indicated temp. i took out mine since we don't have winters here in the philippines. takes a little longer to get up to opeerating temp but no thermo hassles any longer.......

Jim Swantko

When I'm doing long 4th - 5th gear pulls at high boost (30 psi) the head is going to heat. I'll take a little less power over longevity any day.